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Global Plant Letters

International Society for Floricultural and Ornamental Plants "Bringing Ornamental Scientists the World of Plant Science"

©2006, Global Science Books, UK Global Plant Letters, Volume 1, Issue 1 ISSN 1750-2284 Editor-in-Chief: Jaime A. Teixeira da Silva

Index

Editor's note ................................................................................................................................................................. 1 Introducing you to ... Current Trends in Taiwan's Orchid Biotechnology. Ming-Tsair Chan, Sanjaya .................................................................. 2-3 The International Institute of Tropical Agriculture: Research to Nourish Africa. Thomas Dubois, Daniel Coyne, Pheneas Ntawuruhunga, Taye Babaleye, Alexander Schoening, Bas Harbers, Eric Koper ........................................... 3-5 The Outstanding Achievements of Hungarian Science in the 20th Century. E. Tyihák ......................................................... 6-8 The Mesozoic Dicksoniaceous Ferns: Characteristics, Distribution, Origin and Evolutionary Trends. Shenghui Deng, Yuanzheng Lu ................................................................................................................................. 9-29 Scientific summary (January 2006 ­ April 2006). Jaime A. Teixeira da Silva ...................................................................... 30-63 Reviews (January 2006 ­ April 2006). Jaime A. Teixeira da Silva ..................................................................................... 63-66 Open your eyes! Jaime A. Teixeira da Silva ................................................................................................................. 66-67 Useful web-sites. Jaime A. Teixeira da Silva ..................................................................................................................... 67 Meetings and events (May ­ December, 2006). Jaime A. Teixeira da Silva ........................................................................ 67-69 Referencing GPL and Call for contributions. .................................................................................................................... 69

Dear Reader, I wish to take this opportunity of warmly welcoming you to the first Issue of Volume 1 of Global Plant Letters. The birth of the International Society for Floricultural and Ornamental Plants (ISFOP) finds its origin in the need to provide a greater support structure for scientists involved in ornamental and floricultural research. A scan of the literature presently available to plant scientists in either traditional or electronic format reveals a frighteningly broad wealth of information, much of which is often difficult to dissect and synthesize in an effective way. Global Plant Letters, or GPL, will attempt to bring the most significant plant research results ­ lend a guiding hand, as such ­ on a regular basis such that researchers working with ornamentals or floricultural crops may be able to draw on new ideas to expand or diversify nd their research. In this Issue, GPL will also highlight main events, symposia and congresses worldwide in the 2 half of 2006. Not wanting to restrict GPL to ornamental science, we also wish to introduce particular groups of scientists, Institutes or even countries, and their experiences in plant science and/or biotechnology. GSB encourages business, government leaders and members of the public to turn to GPL as a medium for open discussion and an R&D bridge in issues important to ornamental and floricultural scientists such as market analyses, detection of new pathogens, impacts on society, global trends or comments on topical issues. In this issue, GPL introduces an original research paper "The Mesozoic Dicksoniaceous Ferns: Characteristics, Distribution, Origin and Evolutionary Trends" by Shenghui Deng and Yuanzheng Lu that highlights the importance of fossil plants, their research and subsequent conservation. In the light of shrinking global natural fuel reserves and geo-politically- and consumer-motivated price hikes, this manuscript calls on us to be aware of the presence of such important fossil reserves, recognize their existence, and promote a greater appreciation through research. It is the sincere desire of ISFOP and Global Science Books that GPL bring you a refreshing perspective to ornamental and floricultural science. We look forward to your active participation, comments, and contributions. Jaime A. Teixeira da Silva

Current Trends in Taiwan's Orchid Biotechnology

Ming-Tsair Chan* · Sanjaya

Institute of BioAgricultural Sciences, Academia Sinica, Taipei, 115 Taiwan *[email protected]

The Orchids are a group of fascinating plants and represent an

aristocracy in floriculture as cut flowers and potted plants worldwide. Oncidium and Phalaenopsis are indigenous and popular commercial orchid species of the Taiwanese floriculture industry. Taiwan has also emerged as one of the most important orchid export countries, especially in Phalaenopsis orchids. According to statistics from the Bureau of Foreign Trade in Taiwan sales in 2003 accounted for approximately US$20,250,000. Currently, around 200 hectares of land in Taiwan are devoted to cultivating different orchids and most orchid farms are located in Yunlin, Chiayi and Tainan Counties of southern Taiwan. In order to boost the floriculture industry in Taiwan, the government has invested nearly US$22 to $25 million especially for infrastructure development across the country. The rapid and dynamic progress in the area of molecular biology and biotechnology provide a new avenue for the production of new orchid varieties with important characteristics, such as flower pigmentation, disease and pest resistance. In order to keep phase with the growing consumer demand and also to maintain sustainable growth in supply and demand, the Taiwanese government has identified floriculture as a prime area of research and development, and supports researchers around the country working in government and private research centers. The setting up of a separate National Science and Technology Program for Agricultural Biotechnology (NSTPAB) is an interagency program that is implemented and coordinated by the National Science Council, Council of Agriculture and Academia Sinica and its annual budget is around 3% of annual national revenue (Fig. 1). In order to implement cutting edge research,

National Science Council (NSC) Council of Agriculture

NSTPAB has initiated 15 different programmes out of which 5 are allocated to plants, including flower-producing plants and ornamentals. Under these programmes a special emphasis is stressed to develop transgenic technology for the production of high value products including post harvest processing technologies. Currently several principle investigators in Academia Sinica and other laboratories are encouraged to continue long term research goals. Indeed, concentrated efforts are being focusing on enhancing transformation efficiency, introduction of new genes alone or in combination by multi gene approach (gene stacking), exploring new genes which are involved in early/late flower development and subsequent functional analysis and innovation of novel flower specific promoters in floricultural and ornamental plants. The administration consists of a guidance committee, the program advisory committee, a working group, research groups and ad hoc experts from different disciplines. NSTPAB gave a new impetus to the development of the field of modern biology and biotechnology in Taiwan. In more than a decade of its existence, the department has promoted and accelerated the pace of development of biotechnology in the country and has made significant achievements in the growth and application of biotechnology in the broad areas of floriculture with special emphasis on orchid. In Taiwan, more than two decades of concerted effort in research and development in identified areas of floriculture has given rich dividends. The proven technologies at the laboratory level have been scaled up and demonstrated in the field (Fig. 2). Accumulated amount of research publications, numerous researchers and students, several technologies transferred to

Ministry of Economics Ministry of Education

Academia Sinica

Annual budget = 3% of annual national revenue

National Science and Technology Program for Agriculture Biotechnology (NSTPAB)

Total programmes=15

Flower and Ornamental plants

Plant protection

Utilization of plant genomics

Chinese herbal medicine

Post harvest technology and utilization

Fig. 1 Taiwanese major scientific funding agencies for floriculture research

industries and patents filed including Taiwan, Japan and the US, can be considered as modest progress. NSTPAB has been interacting with scientists constantly in order to utilize the existing expertise of the universities and other national laboratories for developing biotechnology application projects

and demonstration of proven technologies. In addition, a strong base of indigenous capabilities has been created. The field of flower biotechnology both for new innovations and applications will form a major research and commercial endeavor for socio-economic development.

Fig. 2 Mass clonal propagation (left) and flowering (right) of Phalaenopsis orchid.

The International Institute of Tropical Agriculture: Research to Nourish Africa

Thomas Dubois1* · Daniel Coyne1 · Pheneas Ntawuruhunga1 · Taye Babaleye2 · Alexander Schoening2 · Bas Harbers2 · Eric Koper2

1 IITA-Uganda: Plot 15, East Naguru Road, Upper Naguru, Kampala, Uganda 2 IITA-Nigeria: Oyo Road, PMB 5320, Ibadan, Nigeria * [email protected]

Introduction

A brief overview of some of IITA's success stories From the onset, plant breeding has been a strong pillar in IITA's research. Numerous improved banana and plantain, cassava, cowpea and yam varieties have been developed. In cowpea, for example, the inheritance of major traits have been elucidated, and genes have been identified which control plant pigmentation, plant and leaf type, growth characteristics, photosensitivity, durations of specific developmental stages, nitrogen fixation, fodder quality, heat and drought tolerances, root architecture, and resistance to major pests, diseases and weeds. In another example and together with Nigerian national scientists, IITA has developed improved seed yam production, yielding high quality, low cost, and abundant planting material. High-yielding cassava varieties have also been produced, allowing for yield increases of up to 40% without the use of fertilizers. More than 200 improved cassava varieties have thus far been released in 20 major cassava-producing countries in sub-Saharan Africa, and by 1998, these improved cassava varieties accounted for 22% of the 9 million hectares planted with cassava in these countries. At IITA, all available tools are employed to meet the challenges of sustainable agriculture and food security. As such, IITA has embraced biotechnology as a new research tool that could revolutionize the face of agriculture in Africa. To facilitate this revolution, IITA and partners have played a pivotal role in ensuring the development and implementation of biosafety policies, laws, and procedures at national and institutional levels. IITA's tissue culture laboratories produce large numbers of

There has been a long drawn awareness about the food shortage

problems in sub-Saharan Africa. Drastic changes in agricultural research and technology transfer strategies are required to enhance local food production by farmers, ensure food security, create wealth, and reduce production risks. The International Institute of Tropical Agriculture (IITA) was founded in 1967 with a mandate to increase the quantity and improve the quality of food in sub-Saharan Africa. It became the first African link in the worldwide network of agricultural research centres supported by the Consultative Group on International Agricultural Research (CGIAR), with headquarters at the World Bank premises in Washington DC. IITA is staffed by about 118 internationally recruited scientists and other professionals from over 30 countries. IITA's mission is to enhance food security, income, and well-being of resource-poor people in sub-Saharan Africa by conducting research and related activities in partnership with national and international stakeholders to increase agricultural production, improve food systems, and sustainably manage natural resources. While IITA headquarters are based in Nigeria, several scientists and research administrators are located at stations in Bénin, Cameroon, Malawi Tanzania and Uganda. Some other researchers are equally working in other countries throughout sub-Saharan Africa. Funding for IITA is essentially derived multilaterally, and channelled through the CGIAR, and bilaterally from national governments and donor agencies.

disease-free plantlets that are vegetatively propagated, such as banana and plantain, and cassava and yam. This work is vital in, for example, combating food security threats such as cassava mosaic disease in East and Central Africa. Conventional breeding efforts are now supplemented with marker-assisted breeding techniques and genetic transformation. Genetic improvement is crucial for crops such as banana and plantain, where conventional breeding remains a difficult endeavor due to long generation times, various levels of ploidy, sterility and limited genetic variability. Another pillar of IITA's research has been geared towards integrated pest management (IPM). Timely, rapid and effective responses to emerging pest and disease threats are needed to guarantee food security and wealth creation. IITA builds on its biological control expertise to develop and introduce to national programs and farming communities a range of eco-friendly options such as biopesticides, botanicals, habitat management and safe use of pesticides. The spectacular control of the cassava mealybug was one of many success stories, which yielded economic returns of 200:1. Biotechnology is equally embraced when conventional avenues to combating Africa's major pests and diseases cannot easily be solved. Transformation of cowpea for resistance to the legume pod borer, and transformation of banana and plantain for resistance against nematodes, fungal infections, and bacterial wilt are examples being explored in collaboration with national institutions. Plant health and crop improvement go hand-in-hand, and this realization led IITA to address with confidence the intensification of cereal-legume systems in the moist and dry savannas of Africa. Targeting improved germplasm to soil problems will lead to resilient and sustainable cropping systems. IITA's maize-soybean rotations combine high nitrogen fixation with the ability to thwart pests, diseases and weeds. A single study, for instance, showed that an improved variety of soybean grown in rotation with maize for just one season could nearly double maize yields. Over the last 20 years IITA has continuously funnelled this improved maize germplasm to national maize research programs in Africa. As a result, close to 50% of the new maize varieties released in 11 countries of West and Central Africa in the 90s originate from IITA. Research at IITA has produced an array of post-harvest technologies that raise the income of rural populations while contributing to the generation of start-up agro-industries that can help to reduce rural unemployment. For example, food technologists at IITA have developed about 150 soybean-based food products with high nutritive value and consumer acceptability. Many of these new products have been assessed in villages across the region, modified by local people to suit local tastes and ultimately adopted. Market-driven agricultural development has been a major thrust for IITA. The focus on improving the standing of the small producer within the overall marketing system by backstopping marketing functions at the country level as well as coordinating regional efforts centers on increasing the economies of scale needed to give producers a comparative advantage. IITA has also conducted market research to lead the way from low agricultural production to market-led agricultural commercialization. For example, IITA clearly revealed that cassava could be transformed from being a poor man's crop to an urban industrial commodity. IITA has longstanding experience in minimizing contamination in crops, such as maize and groundnuts, through development and implementation of management practices that reduce mycotoxins. IITA pioneered research on the effects of aflatoxin on child growth and interactions with health and nutrition. IITA also led an awareness campaign in West Africa,

on the risk of consuming poor quality grains infected with fungal contaminants. Public-private partnerships: vehicles for efficient technology transfer Generation of local technology and development of local capacity have been pivotal at all stages of IITA's research agenda. In addition to increasing African research capability through human and institutional building, IITA's partnerships with national systems have also improved linkages among researchers, extension agents and farmers. Throughout all IITA research activities maximal impact is a key goal, attainment of which can be substantially improved using public-private partnerships. Research for development can benefit greatly from facilitating technology transfer to small-scale farmers from the outset through public-private partnerships. One of the highly successful examples is the Sustainable Tree Crops Program (STCP), which comprises producers, researchers, government agencies, public sector institutions and conservation groups in five West African countries. This framework, based on a facilitated cooperation and coordination among all players involved, streamlines activities ranging from transfer of technology packages to farmers, quality control through certification procedures, to preventing and eliminating child labour abuse on farms. In Uganda and Kenya, IITA has engaged in public-private partnerships with commercial banana tissue culture producers. The technology is increasingly important to enhance planting material for commercial farming. However, pest and disease reinfestation, originating from poorly maintained fields, remains a major hurdle to adoption of the technology by companies embracing this technology. Fungal endophytes offer promise in improving the attraction and suitability of tissue culture materials. Reintroduction of endophytes, which naturally live within plants, into banana tissue culture plantlets is helping to restore the natural pest suppression equilibrium of tissue culture planting materials. Tissue culture plantlets enhanced with natural endophytes are being assessed and made available to farmers `ready-armed' through the involvement and cooperation of private companies. Agro-Genetic Technologies Ltd. in Uganda and Jomo Kenyatta University of Science and Technology in Kenya are key players involved in this venture (Fig. 1). Such public-private partnerships have recently enabled great progress towards bridging upstream research and downstream technology transfer. Unexpected synergisms have additionally emerged through mutual exchange of information and experience, driving

Fig. 1 IITA researchers and employees from Agro-Genetic Technologies Ltd. jointly inoculate banana tissue culture plantlets with endophytes.

Fig. 2 Chicks enjoy cassava-based feed at Ugachick Poultry Breeders Ltd.

the process along commercial thinking. Furthermore, many of IITA's research activities have found applications outside of the African continent. For example, IITA's cowpea varieties have been tested and released in at least 65 countries including in Asia and the Americas, where they have contributed to improved cowpea production and crop-livestock integration. Partly due to IITA's improved varieties, global cowpea production has increased from less than one million ton in 1980 to over four million tons in 2003. Public-private partnerships also sometimes require "out-of-the-box" thinking. In Uganda, for example, the Eastern Africa Root Crops Research Network (EARRNET), a regional network of which IITA is involved, and Ugachick Poultry Breeders Ltd., a commercial production and processing enterprise, are testing the potential of incorporating cassava into animal feeds in a bid to further commercialize the crop. Most feed manufacturers in Africa rely on cereals whose production is dependent on rainfall, leading to scarce supply and competition between human and animal consumption. Cassava, on the other hand, supports a stable production in drought-prone areas and is a rich source of protein, vitamins and minerals, adding to reduced costs of animal feed. Research efforts are being directed at incorporating 10-20% white cassava in broiler feed, while yellow cassava is also being tested in layer feed towards increasing egg vitamin A content (Fig. 2). The collaboration between EARRNET and Ugachick Poultry Breeders Ltd. has been so successful that research will now be extended towards incorporation of other sources into chicken feed. By and large, IITA strives diligently to help protect the environment and human health, such as in the area of pesticide use, by creating public awareness on the harmful effects of pesticides to the environment and human health. Pesticides play a role in African agriculture, as in other parts of the world. However, a lack of awareness by farmers, the presence of outdated and adulterated products and often erratic supply of suitable products can lead to an abuse of pesticide application (Fig. 3). In the drive to more accurately target the efficient and

Fig. 3 A farmer displays an unusable crop of peri-urban carrots following inappropriate use of pesticides.

safe use of pesticides, IITA has teamed up with a major agro-input company in Nigeria, Dizengoff, towards a consistent and nationwide supply of good quality and suitable pesticides, initially focused on the improved production of healthy seed yam. Other potential partnerships with pesticide suppliers and producers are also currently being negotiated towards the reduction, more targeted and safer use of pesticides in general food crop production. Unlikely partnerships, perhaps, but which ultimately lead to improved health conditions and welfare of IITA's primary clients ­ the farmers of Africa. More information More information about IITA can be found at www.iita.org. The STCP Programme is further explained at www.treecrops.org. Detailed concept about public-private partnerships that promote endophyte-enhanced tissue culture is published in the latest issue of the quarterly African Technology Development Forum Journal (www.atdforum.org). EARRNET is available online at http://www.asareca.org/earrnet/. More information on the seed yam work can be found at http://www.nri.org/news/archive/newsarchive2004.htm, while detailed information on the IITA Integrated Cassava Project can be found on www.cassavabiz.org.

The Outstanding Achievements of Hungarian Science in the 20th Century

Ern Tyihák*

Plant Protection Institute, Hungarian Academy of Sciences, Budapest, II. Herman O. út 15. POB 102, H-1525 Hungary * [email protected]

There is a long list of outstanding achievements of Hungarian

Science in past two centuries, however, mainly concentrated in the 20th Century including: Absolute geometry, torsion balance, the carburetor, transformer, electric bulbs with tungsten filaments and krypton charge, radioactive tracing, the nuclear power plant, thermonuclear fusion, the cooling tower, high performance liquid chromatography (HPLC), the electric engine, supersonic flight, radar astronomy, concept of stress, holography, radio television, electronic computer, vitamin C, the helicopter, and the theory of games. These major achievements were contributions by people to whom Hungary was their homeland, who took their best and excellent knowledge and humanity from Hungarian schools, or to whom this country provided shelter and room for their creations. The achievements of Hungarian Science are appreciated all over the world. Derec de Solla Price, professor at Columbia University, writes in the preface to the Hungarian edition of his book Small Science ­ Great Science: "With regard both to absolute degree and per capita indices, it is absolutely clear that Hungary rightfully belongs to that group of countries which, based on its number of inhabitants, economy and industrial development, demonstrates a rather high level of development and certain commitment, primarily research of basic sciences. This is not that surprising, since there is an extraordinary mental capacity which made tiny Hungary into a great country of Nobel-Prize-winning scientists, a country of scientists whose abilities are unparalleled". For the characterization of Hungary we can call on the poet Miklós Radnóti to help: " I cannot know how other people feel about this flame-surrounded little country; out of this I grew as from strong trunks weak branches grow. It is my native land, my childhood's world, I know and hope my body will be buried in this soil." It is known nowadays that in science, the Nobel Prize is the most coveted award presented in recognition of outstanding achievements. In 20th century there have been 12 Nobel Prize winners of Hungarian origin: PHILIPPE A. VON LENARD June 7, l862, Pozsony ­ May 20, 1947, Messelhausen Philipppe Edvard Anton Lenard (Fülöp Lénárd) received the l905 Nobel Prize in Physics for "his atom model (dynamida) based on cathode ray experiments". He was the first scientist born in Hungary to win the Nobel Prize. He lived in Germany and did not consider himself a Hungarian.

ROBERT BÁRÁNY April 22, l876, Vienna ­ April 8, l936, Uppsala Robert (Róbert) Bárány received the Nobel Prize in Medicine for "his work relating to the pathology and physiology of vestibular apparatus". In a speech he delivered upon receiving the Nobel Prize in the discipline of otology. He lived in Sweden. RICHARD A. ZSIGMONDY April 1, l965, Vienna ­ September 23, l929, Göttingen Richard (Richárd) Zsigmondy received the l925 Nobel Prize in Chemistry for "his demonstration of the heteogeneous nature of colloid solutions and for the methods he used, which have since become fundamental in modern colloid chemistry". He lived in Germany. ALBERT SZENT-GYÖRGYI September 16, l893, Budapest ­ October 23, l986, Woods Hole, MA Albert Szent-Györgyi received the l937 Nobel Prize for Medicine for "his discoveries in biological combustion, especially for his discoveries concerning ascorbic acid (vitamin C) and the catalysis of fumaric acid". He was a professor at Szeged University in Hungary from 1928 to l945, and moved to the United States in l947. He is the only scientist ever to receive the Nobel Prize for the results of work carried out in Hungary. GEORGE DE HEVESY August 1, l885, Budapest ­ July 5, l966, Freiburg im Breisgau George de Hevesy ( György Hevesy) received the l943 Nobel Proze for Chemistry for "his work on the use of isotopes as tracers in the study of chemical processes". He lived in Germany, Denmark and Sweden. GEORG VON BÉKÉSY June 3, l899, Budapest ­ June 12, l972, Honolulu, HI Georg von Békésy (György Békésy) received the l961 Nobel Proze in Medicine for "his discoveries of the physical mechanism of stimulation within the cochlea.". He lived in the United States. EUGENE P. WIGNER November 17, 1902, Budapest ­ January 1, l995, Princeton, NJ Eugene Wigner (Jen Wigner) received the l963 Nobel Prize in Physics for "his contributions to the theory of the atomic nucleus and the elementary particles, particularly through the discovery and application of fundamental symmetry theories." He lived in the United States.

DENNIS GABOR June 5, l900, Budapest ­ February 9, 1979, London Dennis Gabor (Dénes Gábor) received the l971 Nobel Prize in Physics for "his invention and development of the holographic method. He lived in Great Britain. JOHN POLANYI January 23, l929, Berlin ­ John Polanyi (János Polányi) is the son of natural scientist: Mihály Polányi. He received the l986 Nobel Prize in Chemistry for "his discoveries in reaction dynamics of chemical elementary processes". He lives in Canada. GEORGE A. OLAH May 22, 1927, Budapest ­ George Olah (György Oláh) received the l994 Nobel Prize in Chemistry for "his contribution to carbocation chemistry". In the field of modern organic chemistry his works overthrew the dogmas of the quattro chemical valency of carbon, opening new opportunities for the manufacture of hydrocarbons. He lives in the United States. JOHN C. HARSANYI May 29, l920 Budapest ­ August 9, 2000, Berkeley, CA John Harsanyi (János Harsányi) shared the l994 Nobel Prize in Economics for "pioneering analysis of equilibria in the theory of non-cooperative games". He showed how games with missing information can be analyzed, laying the foundation for the research of "the economics of information". He lived in the United States. IMRE KERTÉSZ November 9, l929, Budapest ­ He received the 2002 Nobel Prize for Literature for "writing that upholds the fragile experience of the individual against the barbaric arbitrariness of history". His books centre on the horrors of the 20th century: hatred, genocide and inhumanity in human souls. It has to be pointed out that many other Hungarian scientists, while not necessarily Nobel Prize winners, nevertheless have made great achievements to science and technology and received worldwide recognition. Following only a few eminent Hungarian-born scientists will be introduced who contributed to the progress of universal science - they have a place among the greats: ZOLTÁN BAY 24 July, 1900, Gyulavári ­ 4 October, 1992, Washington, DC He was physicist and he was first to use radar to take measurements of the moon. He developed the light meter. He was the member of the Hungarian Academy of Sciences. PAUL ERDS March 26, l913 Budapest ­ September 20, 1996, Warsaw, Poland Paul Erds (Pál Erds) was one of the greatest mathmatician of the 20th century. He wrote over 1500 papers, books and articles, more than any mathematician in history.

CSABA HORVÁTH 25 January, l930, Szolnok, Hungary ­ 2004, New Haven, USA Csaba Horváth is the father of high-performance liquid chromatography (HPLC) which is used successfully all over the world in different laboratories. JÁNOS KABAY 27 December, l896, Büdszentmiháy ­ 29 January, 1936, Budapest He was the first to isolate morphine directly in pure form from plants. He founded the Alkaloida factory in Büdszentmihály. JOHN LOUIS VON NEUMANN 28 December, 1903, Budapest ­ 8 February, l957, Washington, DC John Louis von Neumann (Neumann János) cultivated a number of areas in mathematics from an axiomatic build-up of a general theory of sets to that of ergodicity. The name of Neumann was made world-famous by the role he played in informatics, notably that he is the "father of computers". Neumann was a decisive figure in the American atomic program. He founded the gaming theory. JÁNOS (HANS) SELYE 26 January, 1907, Vienna ­ 16 October, l982, Montreal He as physician, endocrinologist is founder of the concept of stress. He is the "Einstein of Medicine". This is a brief introduction of the outstanding scientific achievements of the Hungarian Nobel-Prize winners of Hungarian origin and a few excellent Hungarian-born scientists who, though not awarded the Nobel Prize, have a place among the greatest of scientists. It is important to try to confirm and remember the secret of these big scientific achievements, and in doing so, some common facts in connection with the excellent Hungarian scientists may be found: 1) By proving the International character of the science they created in several countries, several nations ­ other than Hungary - are proud of their scientific performance. 2) According to Hungarian scientists, secondary schools played a decisive role in achieving such a high performances. 3) The Hungarian Academy of Sciences (HAS) has an important and special mission in maintaining relations with Hungarian scientists living and working outside Hungary. One form of this relationship is the system of external membership. 4) The HAS is a community of excellent Hungarian scientists that has always been an internationally open institution. It has a living, intensive relationship with the international research community (external, honorary membership). 5) Hungarian scientists (e.g. Nobel Prize winners) create good possibilities for young scientists to visit their laboratories. This had been limited in the previous communist system but it is more and more intensive after political system change. The spirit of the Nobel Prize and all big achievements encourage us to build bridges over the walls that separate us. An even longer list of successful Hungarians or Hungarian-born scientists who have enriched science and technological advances

could be drawn up. A sign of just where Hungary stood by the 20th century is amply displayed by a quotation from a biography of Neumann, published in l992 by Norman Macrea, formed editor-in-chief of The Economist and researcher of the Japanese economic miracle. Describing the Hungarian capital at the beginning of the 20th century, he stated that "Budapest was the fastest developing metropolis in Europe. This city produced a legion of scientists, artists and would-be millionaires in numbers only comparable with the renaissance city states of Italy." It is interesting that Nobel Prize recipient Leon Lederman, as he jocularly put it, revealed the secret of Hungarians. According to their "idea" Neumann and others are creatures from outer space who established their first base in our planet in Budapest, and then disguising themselves as Hungarian emigrants spread out, and infiltrated the best universities and research institutes in the world in the first half of 20th century. Let us find out more about the "Martians" who, through their work have exerted such a decisive influence on the culture and history of mankind globally. They reveal their secret themselves. They do not come from outer space; rather excellent Hungarian schooling and basic training ­ including the spirits of Bolyai and Eötvös from the 19th century ­ played a decisive role in their achievements and careers. John (János) Bolyai (1802-1860), mathematician and philosopher, who is the greatest Hungarian scientist wrote to his father Farkas Bolyai (1775-1856), a mathematician, after he solved the problem of parallels, a concept that had remained

unsolved for more than 2000 years: "From nothing I have created a whole new world". The spirit of Bolyai sends a message in this sentence to the coming new generation of the Hungarian scientists as well. Sources used: HAS: Hungary's Nobel Prize Winners; HUNMAGYAR.ORG ­ Hungarian Contribution to Universal Science; Thousand Years of Hungarian Culture. More information on HAS may be obtained from their website: www.mta.hu. Acknowledgements: Thank you to Zsuzsa

Szilágyi of HAS for the below photograph of HAS.

"The Mesozoic Dicksoniaceous Ferns: Characteristics, Distribution, Origin and Evolutionary Trends" Shenghui Deng and Yuanzheng Lu Far too often do we hear of record high gas prices and how events, comments or ideologies in the Middle East, Africa and/or South America influence crude oil and subsequently gas prices at the pump. Rising oil prices and apprehension about global warming are prompting governments to rethink their energy supply policies. As oil, a non-renewable resource, begins to decline, and oil prices continue to fluctuate unpredictably, the search for new oil fields will be inevitable to quench oil-thirsty nations whose driving habits and dependence on oil for transportation, the backbone of their economies, continue to grow. In that sense Brazil is a clear example of the way in which the world could be moving: ethanol-based gasoline. Petrology (including petrography and petrogenesis), a branch of geology, deals with the origin, composition, structure, and properties of rocks, primarily igneous and metamorphic, and secondarily sedimentary. Deng and Lu take a paleantological approach to explaining the importance of geological plant resources prior to petrological exploration. In this day and age, where the tendency is to explore natural resources without much reflection on past historical origins or on the future consequences of these explorations, a greater attention needs to be paid to paleontological treasures. Deng and Lu bring a real case study, the Dicksoneaceous ferns, to increase our awareness to how we perceive the origin of gas reserves, how to further appreciate it, and ultimately to respect it. Jaime A. Teixeira da Silva

Original Research Paper Manucript received: 2 February, 2006. Manuscript accepted: 12 April, 2006

Global Plant Letters 1(1), 9-29 © 2006 Global Science Books, Ltd., UK

The Mesozoic Dicksoniaceous Ferns: Characteristics, Distribution, Origin and Evolutionary Trends

Shenghui Deng* · Yuanzheng Lu

Research Institute of Petroleum Exploration and Development, Beijing, 100083, China * [email protected]

ABSTRACT

The Dicksoniaceae are very important in Mesozoic floras, occupying a dominant position in the fern group. They are significant and important for the subdivision and correlation of the Jurassic and Cretaceous strata bearing coal, oil and gas in China, Central Asia and Siberia. The main characteristics of the Mesozoic dicksoniaceous ferns are dealt with in the present paper. The temporal origin of these ferns is possibly the beginning of the Early Jurassic and while the geographic origin is probably in East Asia. The family gradually developed in the Early Jurassic, rapidly expanded during the latter part of the Early Jurassic and then reached its first developing peak with greatest diversity and largest distribution in the early Middle Jurassic. The family established its second developing peak during the Early Cretaceous after a great reduction in the Late Jurassic caused by an arid climate. But how this family declined after the Early Cretaceous to become a small family characterized by tree or tree-like types, and are mainly distributed in the tropics of the Southern Hemisphere still remains an elusive topic. The evolutionary trends of the outlines of the plant and its reproductive organs are also discussed. Keywords: characteristics, Dicksoniaceae, distribution, evolutionary trends, origin

INTRODUCTION

The

continental Jurassic and Cretaceous systems are well developed and widely distributed in China, Central Asia and Siberia. The Lower-Middle Jurassic in North China and Central Asia, and the Lower Cretaceous in North China and Siberia are characterized by fluvial, lacustrine and marsh sediments, typically by dark mudstones and coal-bearing units, which are oil and gas source rocks. In China, about 60% and 7% of the total coal resources are borne in the Lower-Middle Jurassic and Lower Cretaceous, and 44.7% of oil and 20% of natural gas are found from the Mesozoic strata, and the Cretaceous and Jurassic occupy the first and the fourth position of the oil resource. The source rocks and reservoir beds of the Turpan-Hami Oil Field of Xinjiang, Northwest China are the Jurassic system and the largest oil field in China, the Daqing Oil Field and many other oil and fields are borne in the Cretaceous rocks. To subdivide and correlate the strata and to determine the geological age of the source and reservoir rocks are important bases for coal, oil and gas exploration and development. Palaeontological studies can provide the key evidences for these problems. However, for the continental Mesozoic stratum studies, plant is one of the most important fossil groups, of which Dicksoniaceae are important fern family in the Jurassic and Cretaceous floras. They are of great stratigraphical significance due to their rapidly evolution and having many index fossils, such as Coniopteris hymenophyllum, Eboracia lobifolia and Acanthopteris gothani.

These fossils can indicate a relatively exact age of the stratum bearing them and show the correct relationship between the strata in different areas. Therefore, studies on the Mesozoic dicksoniaceous ferns are significant for stratigraphy, geology and oil, gas and coal exploration. The Dicksoniaceae is a very fantastic fern family. They are one of the few extant tree fern groups and are very beautiful and important garden plants. The living Dicksoniaceae are tree ferns or tree-like ferns, arborescent or not, having stout, prostrate or erect stems (Copeland 1947, Tryon and Tryon 1982, Wu and Ching 1991). It is a rather smaller family in the living fern group, with about 40 species belonging to 5-6 genera, which occupy a very small position compared to a total number of more than 10,000 species of the modern ferns. Most of the extant Dicksoniaceae live in the tropic climatic zone of the Southern Hemisphere, but some can be distributed in the South Temperate Zone such as the south of New Zealand (Fig. 1; Tryon and Tryon 1982). However, the Mesozoic dicksoniaceous ferns are rather different. They occupied a main position of the fern groups in the Middle Jurassic and Early Cretaceous, and were widely distributed, ranging from the tropics to the temperate zones of the world, even in both the Arctic and Antarctic. Furthermore, the Mesozoic dicksoniaceous ferns were mostly spread out over the Northern Hemisphere. Additionally, although we do not have knowledge of all the Mesozoic dicksoniaceous ferns, none from the Jurassic and Cretaceous have been demonstrated to be tree ferns (Deng 2002).

Fig. 1 Distribution of the extant Dicksoniaceae.

The Dicksoniaceae are very interesting to both botanists and palaeobotanists because they are a relict of the ferns that lived in the dinosaur age but are quite different from their ancestors, and having many concerned problems that still remain unsolved, particularly their origin and evolution. The oldest possible dicksoniaceous fossils have been claimed from the Upper Triassic (Palaeobotanic and polynologic Section of the Beijing Botany Institute, Academia Sinica, 1976); however, most palaeobotanists believe that Dicksoniaceae appeared first in the latter part of the Early Jurassic. Based on the incomplete data, more than 80 species attributed to Coniopteris, Dicksonia, Eboracia, Kylikipteris, Gonatosorus, Acanthopteris and Culcitites from the Mesozoic have been considered as dicksoniaceous ferns, and usually they dominated the fern group of the Mesozoic floras. Two flourished periods of this family, which are Middle Jurassic and Early Cretaceous, respectively, have been recognized. But, the details of their evolutionary pattern from the Mesozoic to modern time still need much attention. From the mid 1980's, the author (SH Deng) began his studies on the Cretaceous floras of Northeast China (Deng 1995, Deng et al. 1997), and most of his work concerned the ferns, including 12 species belonging to the Dicksoniaceae (Deng 1992, Deng and Chen 1997 2001). In the last decade, Deng focused his studies on the Jurassic floras of North China (Deng et al. 2000 2003). Based on these previous studies and on the literature, this paper will deal briefly with the main characters of the Mesozoic dicksoniaceous ferns, their distribution, origin and evolutionary trends.

CHARACTERISTICS OF THE MIDDLE MESOZOIC DICKSONIACEAE

Sterile fronds The Mesozoic Dicksoniaceae are usually herbaceous plants with compound pinnate leaves of medium to large size. Most of them are up to 50-100 cm high (Fig. 2), but some are possibly less

Fig. 2 Reconstruction of Acanthopteris gothani Sze (after Deng and Chen 2001).

than 20 cm high (Plate 3 - Fig. 4) especially those early species in the Early Jurassic (Deng 2002, this paper; Plate 1 - Fig. 7). Most species have bipinnate fronds, with few having tripinnate fronds. At least some of the rhizomes of these ferns are of a creeping type (Plate 2 - Fig. 1; Plate 3 - Fig. 2). So far, there is no strong evidence to indicate the existence of a tree fern or tree-like fern in the Mezoic. The pinnules are usually sphenopterid, but some are pecopterid, such as Kylikipteris of the Jurassic (Harris 1961) and Acanthopteris of the Early Cretaceous (Deng and Chen 2001). Acanthopteris was established by Sze in 1931 while the same fossils from Russia and Japan were usually assigned to its junior synonym Birisia (Samylina 1972).

Fertile fronds The Mesozoic dicksoniaceous ferns are usually independent (Plate 1 - Figs. 3, 5-6, 10), but in some cases, the fertile pinnae are borne at the upper region of the frond, or only some of the pinnules of a pinna are fertile. As examples, Acanthopteris gothani and Coniopteris longipinnata from the Early Cretaceous of Northeast China have fertile pinnules mixedly borne in the lower regions of a pinna (Plate 1 - Fig. 2; Plate 2 - Fig. 2), or fertile pinnae in the upper regions of a frond (Fig. 2). The fertile pinnules of dicksoniaceous ferns are usually strongly contracted to stick-like, but a few species, such as Eboracia lobifolia of Jurassic and Coniopteris longipinnata of Cretaceous have slightly contracted fertile pinnules.

Table 1 Main characters of the reproductive organs of the dicksoniaceous ferns from the Middle Jurassic Yorkshire Flora. Species Sori Sporangia Spores per sporangium about 64 Equatorial outline and diameter (µm) of spores Rounded triangular, 46-(55)-61 Ornamentation of spores

Coniopteris bella

C. concinna

C. margaretae

C. murrayana

C. hymenophylloides

Sorus wider than the filiform segment bearing it; indusium membranous, thin, slightly longer than broad, free end divided into an upper and lower lobe, margin entire, placenta flat Sori borne singly on lower lateral lobes and pointing forwards; indusium cup shaped Sori stalked, semicircular, 4-5 mm wide, inner end often overlapping on pinna rachis, height 2 mm; indusium cup shaped, thick, edges entire Fertile leaf slightly reduced; sori small, 0.5 mm wide; indusium cup shaped, rather thick, margins slightly lobed Indusium cup shaped, smooth, membranous, placenta flat Sori slenderly stalked, indusium cup shaped, 1.5 mm wide Sori borne singly on apex of pinnule, stalked, circular; indusium thick, smooth inside and outside Sori 1-4 on each margin, sporangia numerous

Sporangia globular, diameter 200 µm, shortly stalked, annulus well developed

Exine marked with tiny granules; perine granular, granules 0.5-1 µm in diameter

Sporangia stalked, 250 µm wide, annulus developed

Rounded triangular, 34-(40)-50

Exine almost smooth, with several small pits near the tetrad scar; perine unknown Exine marked with tiny granules and pits; perine granular, granules 1.5-2 µm in diameter

250µm wide, annulus probably completed

Rounded triangular, 62-(76)-94

Sporangia rather small, 200 µm wide, annulus developed

Rounded triangular, 32-(43)-59

Almost smooth exine; perine granular, granules 1 µm in diameter

Sporangia elliptical, 400 µm long, 250 µm wide

Rounded triangular, 34-(40)-52

C. simplex

Sporangia shortly stalked, annulus composed of about 25-30 cells Sporangia about 200µm in diameter

50-100

Triangular-rounded triangular, 36-(45) -55

Kylikipteris arguta

Rounded triangular, 34-(45)-56

Eboracia lobifolia

Sporangia shortly stalked, about 200 µm long, annulus well developed About 200 µm wide

about 60

Triangular, 27-(33)-41

Dicksonia kendalliae

D. mariopteris

Sori borne singly on the first acroscopic vein of a fertile pinnule; indusium composed of two valves, edges entire Sori 1-5 borne laterally on both sides of a pinnule, broadly oval, 2.5 mm wide, height 1.5 mm; indusium composed of two valves, small, rather thick, outer edges entire

Rounded triangular, 34--(52)-61

Exine marked with tiny granules; perine granular, granules 1-1.5 µm in diameter Exine nearly smooth, slightly pitted near the tetrad scar; perine granular, granules 1.5 µm in diameter Exine nearly smooth; perine marked with tiny granules, granules <0.5 µm in diameter and fused to form an irregular micro-reticulum Exine almost smooth but slightly pitted; perine irregular reticular, meshes 1.5-2µm in diameter Exine nearly smooth, with tiny pits near the tetrad scar; perine reticular, meshes 2 µm in diameter Exine almost smooth, but tiny pits distributed all over the spore, the larger concentration occurring near the tetrad scar; perine reticular, meshes 1-1.5µm in diameter

300 µm wide, annulus well developed

Rounded triangular, 24-(33)-56

Based on Harris TM (1961) and Van Konijnenburg-van Cittert (1989)

Table 2 Main characters of the reproductive organs of the Early Cretaceous dicksoniaceous ferns from China. Species Coniopteris concinna Fertile pinnae Strongly contracted, independent Sori Sori quite large in size, elliptic or nearly rounded, transversal placed, about 1.5 mm long; indusium cup shaped, rather thick Sporangia Elliptic, 150~200 µm in diameter, annulus nearly vertical, incomplete, consisting of 25 thickened cells Spores per sporangium 64 Shape of spore Rounded triangular in polar view, margins slightly concave or straight, a few spores having slightly convex margins, about 50-60 µ in m diameter, a few over 65 µ ; trilete, leasurea m thin, straight, about 2/3-3/4 of radius ? Ornamentation of spores Exine marked with fine granules, proximal face pitted

. densivenata

Strongly contracted, independent

C. ermolaevii

Strongly contracted, independent

Sori quite large in size, elliptical or nearly rounded, 1.5 mmin diameter, the top sorus larger than others and cap-shaped, transversely placed; indusium unknown Sori small in size, diameter <1mm, indusium cup shaped

?

?

?

Elliptic, 140×210 µm in diameter; annulus nearly vertical, incomplete, consisting of 20 thickened cells

56-64

C. huolinheensis

Strongly contracted, independent or borne in the lower regions of the fronds

Sori large in size, elliptic, transversely placed, 2 mm wide, 1.5 mm height, indusium unknown

Elliptic, 150-250 µ m in diameter; annulus nearly nearly vertical, incomplete, consisting of about 25 thickened cells

64

C. longipinnata

Relatively slightly contracted, independent or in the lower regions of the fronds, 1-3 sori in each pinnule. Strongly contracted, independent Strongly contracted, independent

Sori quite small in size, 0.6-1.0 mm in diameter, elliptic, indusium unknown

globular, 160-200 µ m in diameter, annulus nearly vertical, incomplete, consisting of about 15 thickened cells

50-60

Rounded triangular in polar view, margins slightly convex, a few subrounded, 35-45 µ m in diameter, trilete, laesurlae thin, straight, nearly reaching the equator Usually triangular or subtriangular, margins slightly concave or convex, a few rounded triangular, 25-35 µ in diameter, m trilete, laesurae thin, straight, nearly reaching the equator Triangular or subtriangular in polar view, margins slightly concave or convex, 30-40 µ in diameter, m trilete, laesurae narrow and straight, nearly reaching the equator ?

Exine smooth

Exine nearly smooth, finely granular under Scanning electronic microscope

Exine smooth

C. onychioides

C. setacea

Sori quite small in size, nearly rounded, about 0.8 mmin diameter; indusium cup shaped Sori small in size, indusium unknown

?

?

?

200 µ in diameter; m annulus nearly vertical, incomplete, consisting of about 25 thickened cells

64

C. vachrameevii

Strongly contracted, independent

Sori quite large in size, about 1 mm in diameter, indusium unknown

Elliptic, 140×200 µ m in diameter; annulus nearly vertical, incomplete, consisting of 20 thickened cells

50-64

C. venusta

Strongly contracted, in the top of the fronds, usually two sori in each pinnule

Sori large in size, trapezoidal, transversely placed, 1-2 mm wide; indusium probably bivalve-like

globular, 200-250 µ m in diameter; annulus oblique, incomplete, consisting of about 22-25 thickened cells

?

Triangular, margins slightly concave, only very few slightly convex, 35-45 µ in m diameter, trilete, laesurae thin, straight, cracked in ripe spores, about 3/4 of radius long Rounded triangular in polar view, margins slightly concave, few subrounded, 30-35 µ m in diameter, trilete., laesurae rather thick, nearly reaching the equator Rounded triangular in polar view, margins convex, 60-70 µ in m diameter, trilete, laesurae 3/4 radius long

Exine smooth

Exine finely granular, with pits along the laesurae

Exine thick, marked with fine granules

Table 2 (cont.) Dicksonia silapensis Strongly contracted, independent Sori quite small in size, <1 mm in diameter; indusium bivalve-like, rather thick globular, 150~200 µ m in diameter, annulus nearly vertical, incomplete, consisting of about 20 thickened cells Elliptic, 200×250 µ m in diameter, annulus nearly vertical, incomplete, consisting of about 20-25 thickened cells 64 Rounded triangular in polar view, margins slightly convex, about 35 µ in diameter, m trilete, laesurae thin Rounded triangular in polar view, margins slightly concave or convex, 30-35 µ in m diameter, trilete, laesurae thick, nearly reaching the equator Exine granular, granules, 0.1-0.3 µm in diameter

Acanthopteris gothani

Strongly contracted, independent or in the lower regions of the fronds

Sori quite large in size, circular, about 1-1.5 mm in diameter; indusium transitional, fused in the lower but divided in the upper part, membranous, free end divided into 4-6 broad triangular teeth

64

Exine nearly smooth, or with some 0.5-1 µ sized m granules

Table 3 Main characters of the reproductive organs of the living dicksoniaceous ferns. Genera Cystodium Indusium bi-valve Sori Form and size Rounded triangular in polar Annulus slightly oblique, view, margins convex , discontinuous at stalk, 32 semicircular in equatorial spores per sporangium view, 32×49 µm in size Triangular in polar view, Shortly stalked, annulus margins concave, 33×56 µm oblique, 64 spores per in size sporangium Rounded triangular in polar Annulus slightly oblique, interrupted by the stalk, 64 view with straight margins, 28×45 µm in size spores per sporangium Rounded triangular in polar 64 spores per sporangium view, margins strongly convex, 26×37 µm in size Rounded triangular in polar Pyriform, stalk long, annulus slightly oblique, 64 view, with thickened angles, (34~40) ×(48~60) µm in size spores per sporangium Rounded triangular in polar Annulus slightly oblique, continued at stalk, 64 spores view, with thickened angles, 44~68 µm in size per sporangium Sporangium Spore Perine Exine With strips and lines in Fine granular the unripe spores, but granular in ripe ones Two layers, verrucate, Relatively plain papillate ? laesurae 15 µm long, about 2/3 of spore radius

Thyrsopteris Apical, indusium cup-shaped Sori marginal, at the ends of the veins, indusium bi-valved Calochlaena ? Culcita

With a margo, 23µm long

?

16 µm long, about 3/4 of Almost smooth, the radius pitted near the laesurae Spinate, verrucate 13 µm long, about 2/3-3/4 of the radius Margo thickened and pitted, length about 2/3 of the radius Smooth or ridged, Length about 3/4 of the radius often pitted irregularly Smooth

Cibotium

Sori marginal, at the ends of the veins, indusium bi-valved Sori marginal, indusium bi-valved

Granular, papillae, distal surfaces ridged Two or more layers, smooth or coarsely reticulate

Dicksonia

Based on Tryon and Tryon (1982 1991), Gastony (1981 1982)

Sori The sori of the Mesozoic dicksoniaceous ferns are usually borne at the ends of the contracted fertile pinnules. But in some species such as Eboricia lobifolia and Coniopteris longipinnata, the sori are marginally arranged in the slightly contracted or non-contracted pinnule membranes. Typically, every pinnule has 3-6 pairs of sori, and commonly one sorus to one lobe of the pinnule. Some species, such as Coniopteris longipinnata, have only 1-3 pairs of sori in each pinnule. Gonatosorus is a genus characterized by one sorus in each pinnule. The sizes of the sori are usually about 1 mm in diameter. Jurassic species, such as Coniopteris sp. (Plate 1 - Figs. 5, 6), C. gansuensis (Cao and Zhang 1996), C. margaretae (Harris 1961; Table 1), C. macrosorata (Li et al. 1988) and some Cretaceous species, such as Coniopteris huolinheensis (Plate 1 - Fig. 10), C. venusta and Acanthopteris gothani (Table 2) have sori of over 1.5 mm or even 3.5 mm in diameter. In contrast, some Early Cretaceous species, such as Coniopteris setacea and C. onychioides have smaller sori, unusually less than 1 mm in diameter (Table 2). Most Coniopteris species have rounded sori, and Dicksonia and Gonatosorus have usually elliptic and transverse sori. Three types of indusia have been recognized (Deng and Chen 2001). Cup-like indusia are represented by Coniopteris (Harris 1961, Chen et al. 1990), bivalve-like type by Dicksonia (Harris 1961, Deng and Chen 2001) (Plate 4 - Figs. 2, 3), and a transitional type by Acanthopteris (Deng and Chen 2001). This transitional type is characterized by a cup-like lower part while the upper

part is divided into two valves. According to Van Konijnenburg-van Cittert (1989), Eboracia has also transitional type indusia. Sporangia According to the observations of about 20 species of dicksoniaceous ferns from the Jurassic and Lower Cretaceous of China (Table 2) and 10 species of the Yorkshire flora (Harris 1961; Table 1) and some others (Jordan et al. 1996), the outlines of the sporangia are similar to each other. The sporangia are usually globular or ellipsoidal in shape. The size of sporangia range from 100 to 400 m in diameter. Those of Jurassic species are a little larger, usually over 200 m in diameter. The maximum size is that of Coniopteris hymenophylloides from the Middle Jurassic, reaching up to 250 × 400 m (Harris 1961; Table 1), while Cretaceous sporangia are relatively smaller, usually 150-200 m. The sporangia have a slender stalk more than 100 m long and 15-20 m wide (Plate 3 - Fig. 3). The annuli appear erect or almost erect (Plate 2 - Fig. 3; Plate 3 Figs. 3, 7; Plate 4 - Fig. 5), incomplete, starting at the base of the stalk, and are about 3/4-4/5 of the circumference of the sporangium in length. The annuli are usually composed of 20-25 thickened cells (Plate 2 - Fig. 2; Plate 3 - Fig. 7), very few are over 25 but never up to 30, with only Coniopteris longipinnata being below 20 (Table 2). It is difficult to count the exact number of sporangia in each sorus since these are incompletely preserved. However, our statistics show that it is usually about

30 or even more. The number of spores per sporangium is relatively easier to calculate. Our results of 8 species show that the numbers are on average usually 50-60, but may range from a few up to 63 or 64 (Table 2). However, according to Harris' account (Harris 1961), the English Middle Jurassic Yorkshire Flora species have quite a variable number of spores, some are even over 64. But our counts of 2 species of Coniopteris and Eboracia lobifolia from the Jurassic of China show 64 or a little bit fewer. Therefore, we guess that Harris 1961 may have made a miscalculation. Jordan et al. (1996found that Dicksonia dissecta, a Tasmania (Australia) species from the Oligocene of Tertiary has 64 spores per sporangium. All the genera of the extant dicksoniaceous ferns have 64 spores per sporangium except Cystodium that has only 32 (Table 3). Consequently, we suggest that the spore output of the most Mesozoic dicksoniaceous ferns, including Coniopteris, Dicksonia and Acanthopteris should be 64. Spores Morphologically, the mature spores of a species are similar to each other, showing a stable feature. They all are tetrahedron. Most are rounded triangular in polar view, with straight or slightly convex edges, and a smaller number of the spores have concave edges (Tables 1, 2). Coniopteris setacea serves as an example, in which the spores are mainly triangular, while most of the species such as, Coniopteris huolinheensis, C. concinna, have chiefly rounded triangular (Plate 3 - Fig. 6). However, the young spores are rather different from mature ones in shape. They have usually concave margins (Plate 2 - Fig. 5). The size of the spores of a species are sometimes much more variable, particularly in Coniopteris concinna, in which about 5% of the spores are over 60 m , while others are generally 40-50 m in diameter. In contrast, some species, such as Coniopteris longipinnata and Dicksonia silapensis have similar sized spores Deng and Chen 2001. The spore size of different species is variable. As shown in Table 2, the largest spores of the Early Cretaceous species from China are those of C. venusta, which is about 60-70 m in diameter, Coniopteris concinna ranks second, with about 40-50, while others are usually 30-40 m. Among the ten species of the Yokshire Flora (Harris 1961), eight have spores with an average diameter over 40 m, three over 50 m, with the maximum size being up to 74 m (Table 1). Two different types of laesurae have been found. One is ridge-like, another is crack-like. These two types have been found to be present in the spores from one species or even from one specimen. Usually the young spores have mainly a ridge-like type, while the ripe ones have both a crack type and ridge line type. Unripe spores commonly have relatively thicker but sinuate ridge-like laesurae (Plate 2 - Fig. 5). Slight differences in morphology of the laesurae have been observed in different species. Coniopteris setacea has thin but straight ridge-like laesurae, while Coniopteris vachrameevii and Acanthopteris gothani have relatively thick laesurae. The length of the laesurae are usually 3/4-7/8 of the radius of the spores, but almost invariable between different species. Van Konijnenburg-van Cittert (1989) claimed that there are specific differences of the laesurae length, which are 3/4, 4/5, or 7/8 of the radius in different species. But, according to our observation, these slight differences may also be observed in different spores of same species, but is difficult to measure due to the

preservation. The ornamentations of the perispores of the living ferns are very different and very significant in species identification. But in fossil spores, it is quite difficult to judge if there are perispores. Perispores are generally weak and difficult to be preserved through the geological period and the diagenesis and might be destroyed during treatment by chemicals in the laboratory. Van Konijnenburg-van Cittert (1989) claimed that some species of the Yorkshire dicksoniaceous ferns have granularly or reticulate sculptured perispores. She believed that the sculptured surfaces she observed are perispores while the smooth surfaces are exines. In our observation, most of the Jurassic and the Early Cretaceous species have a smooth surface (exines) except for a few species, such as Eboracia lobifolia and Dicksonia silapensis (Plate 4 - Fig. 4). But we also found sculptured spores and smooth spores that came from one species. In Acanthopteris gothani, for example, the unripe spores have a generally granular ornamentation, but ripe ones are usually smooth (Plate 2 - Fig. 4). However, further observation under a scanning transmission microscope is needed to distinguish the perispores and exine. The unripe spores are characterized by a smaller size, lighter colour, thinner exines with more wrinkles, usually in a triangular shape with concave sides and relatively thicker but sinuate ridge-like laesurae (Table 4).

Table 4 Characters of unripe and ripe spores of the Early Cretaceous dicksoniaceous ferns from China. Item Shape Size Outer surface Colour Laesurae Unripe spores Triangular with concave margins Smaller, usually 20 m Thin, with many wrinkles usually light yellow ridge-like, relatively thicker, sinuate Ripe spores Rounded triangular, straight or slightly convex Larger, 30-60 m Thick, fewer wrinkles yellow or yellowish brown Cracked or ridge-like, thin, straight

COMPARISON BETWEEN THE MESOZOIC AND THE EXTANT TYPES

The living Dicksoniaceae are usually subdivided into Thyrsopteris, Cystodium, Cibotium, Dicksonia and Culcita though there are opinions of dividing Culcita into subgenera Culcita and Calochlaena based on their sori and of considering Calochlaena as an independent genus (Whiter and Jurner 1988). All these genera and subgenera are tree ferns or tree-like ferns of several meters to over a dozen meters tall, with stout, prostrate or erect stems and 1-3 m long pinnae (Wu and Ching 1991, Tryon and Tryon 1982). But most of the known Mesozoic dicksoniaceous ferns are herbaceous plants, while no definite tree ferns of this family have yet been reported from the Mesozoic (Deng and Chen 2001). The biggest fronds of the Mesozoic dicksoniaceous ferns are less than one meter long, and the rachis are generally several millimeters to one centimeter thick. The Mesozoic dicksoniaceous fronds are commonly associated with numerous rhizomes in the sediments (Sun 1986, Deng 1995). These rhizomes are creeping, and not very thick (Plate 3 - Fig. 2). Furthermore, there is a specimen showing the fronds attached to the creeping rhizome (Plate 2 - Fig. 1). Consequently, we believe that the Mesozoic dicksoniaceous ferns are mainly herbaceous plants though there is the possibility that tree ferns exist. The Mesozoic dicksoniaceous ferns are

Plate 1 (1, 9) Eboracia lobifolia (Phillips) (1) Sterile frond, (9) Fertile frond; from the Middle Jurassic Xishanyao Formation of Turupan-Hami basin, Xinjiang, Northwest China. (2, 12-13) Coniopteris hymenophylloides Brongniart (2) Fertile frond, (12-13) Sterile fronds showing the abnormal basal pinnules on the basiscopic side(arrows); from the Middle Jurassic Xishanyao Formation of Turupan-Hami basin, Xinjiang, Northwest China. (3-4, 8) Coniopteris simplex (L. & H.) Harris. (3) Fertile fronds, from Middle Jurassic Yima Formation of Henan Province North China; (4, 8) Sterile fronds, from the Middle Jurassic Xishanyao Formation of Turupan-Hami basin, Xinjiang, Northwest China. (5-6) Coniopteris sp. (5) Fertile pinna showing big sori, × 2, from Lower Jurassic Sangonghe Formation of Junggar basin, Xinjiang, Northwest China; (6) Fertile pinna showing big sori, × 2, from Early Jurassic Sangonghe Formation of Turu-Pan basin, Xinjiang, Northwest China. (7) Coniopteris gaojiatianensis Zhang fertile pinna, from the Lower Jurassic Badaowan Formation, Junggar Baisn, Xinjiang, Northwest China. (10-11) Coniopteris huolinheensis Deng. (10) Fertile pinna, showing large sori, (11) Sterile frond; from the Lower Cretaceous Huolinhe Formation of Huolinhe basin, Nei Mongol, Northeast China.

Plate 2 (1-5) Acanthopteris gothani Sze. (1) A whole plant, from the Lower Cretaceous Huolinhe Formation of Huolinhe basin, Nei Mongol, Northeast China; (2) Frond showing the fertile pinnules in the lower regions of the pinnae, from the Lower Cretaceous Xiaoming'anbei Formation of Tiefa basin, Liaoning, Northeast China; (3) Sporangium, showing the annulus, bar = 50 m; (4) Spores showing the ripe spores, bar = 20 m; (5) An unripe spore, bar = 5 m; all sporangium and spores are from the materials collected from the Lower Cretaceous Xiaoming'anbei Formation, of Liaoning (Deng and Chen 2001).

Plate 3 (1-3) Acanthopteris gothani Sze. (1) Sterile fronds, arrows showing the intercalated pinnules, from the Lower Cretaceous Xiaoming'anbei Formation of Tiefa basin, Liaoning, Northeast China; (2) Creeping rhizome with stipes and buds, from the Lower Cretaceous Huolinhe Formation of Huolinhe basin, Nei Mongol, Northeast China; (3) Sporangium, showing the annulus and stalk, bar = 50 m, from the material collected from the Lower Cretaceous Xiaoming'anbei Formation of Tiefa basin, Liaoning, Northeast China. (4) Coniopteris setacea (Pryn.) Vachrameev. Sterile pinna, from the Lower Cretaceous Xiaoming'anbei Formation of Tiefa basin, Liaoning, Northeast China. (5) Coniopteris ermolaevii Vassilevskaja. Sterile pinna, from the Lower Cretaceous Xiaoming'anbei Formation of Tiefa basin, Liaoning, Northeast China. (6) Coniopteris concinna (Heer) Chen, Li et Ren. Spores, bar = 20 m, from specimen collected from the Lower Cretaceous Yimin Formation, Hailar basin, Nei Mongol, Northeast China (Deng and Chen 2001). (7) Coniopteris vachrameevii Vassilevskaja. Sporangium showing the annulus, bar = 50 m, from the specimen collected from the Lower Cretaceous Xiaoming'anbei Formation of Tiefa basin, Liaoning, Northeast China.

Plate 4 (1-4, 6) Dicksonia silapensis (Pryn.) Meng et Chen. (1) Sterile frond, (2-3) Showing the bivalve-like indusium, bar = 100 m and 50 m. (4) Spores, showing the granular sculpture, bar = 2 m; (6) Fertile frond; all were from the Lower Cretaceous Xiaoming'anbei Formation of Tiefa basin, Liaoning, Northeast China. (5, 7) Coniopteris vachrameevii Vassilevskaja. (5) Sporangium showing the annulus, bar = 50 m; from the materials collected from the Lower Cretaceous Xiaoming'anbei Formation of Tiefa basin, Liaoning, Northeast China. (7) Sterile frond; from the Lower Cretaceous Fuxin Formation of Fuxin basin, Liaoning Northeast China.

much smaller than the living types. They are about one meter tall or less. The fossil dicksoniaceous ferns have not been studied completely due to incomplete preservation. The anatomic characters of rachises or stems of the Mesozoic dicksoniaceous ferns are unknown. The most comparable parts of the fossil and living types are the reproductive organs (Table 3). Coniopteris is identical to Thyrsopteris in its cup-shaped indusia (Harris 1961, Chen et al. 1990, Deng and Chen 2001); fossil Dicksonia and Eboracia have bivalve-like indusia, the same as living Dicksonia and Calochlaena (Harris 1961, Klassilov 1978, Deng and Chen 2001). The sporangia of the extant Dicksoniaceae are globular, with a rather long stalk as in Culcita or a short stalk as in Calochlaena (White and Jurner 1988). The stalks of the fossil sporangia are difficult to observe, but sometimes we found parts of stalks (Plate 3 - Fig. 3), which indicate their slender nature. The annuli of the living species are all oblique, but most of the fossil species are possibly vertical or nearly vertical, except for those of Coniopteris venusta, which are oblique (Table 2). The spore output (spore number per sporangium) of Thyrsopteris, Culcita, Cibotium and Dicksonia are 64, but Cystodium has 32 spores per sporangium (Table 3). All the known fossil species have 64 spores (Jordan et al. 1996, Deng and Chen 2001). The spores of the living dicksoniaceous ferns are commonly triangular in polar view Gastony 1981 1982), trilete, usually 30-40 m in diameter (Table 3). These spores have thick perispores, which enlarge the size of the spores considerably. Based on pictures by Gastony (1981 1982), the spores with perispores of Cystodium sorbifolium are about 78 m in diameter, but only 44 m without perispores (Fig. 15 in Gastony 1981), spores without perispores of Culcita coniifolia are 46 m (Fig. 18 in Gastony 1981); spores with perispores such as in Cibotium glacucum are 80 m but 44 m without perispores (Fig. 20 in Gastony 1982;), spores without perispores of Cibotium wendlandii are 44 m (Fig. 39 in Gastony 1982). These sizes are similar to those of the Cretaceous types, particularly those of Coniopteris setacea, but smaller than the Jurassic ones. The spores of the fossils are more or less rounded, while most of the living species, such as Cibotium glaucum and Thyrsopteris elegans, have spores with straight or slightly convex sides, and more triangular in form. However, the ripe spores of Cystodium sorbifolium are in rounded triangular forms, with three rounded angles, similar to the Jurassic Eboracia lobifolia and the Early Cretaceous Coniopteris coninna (Plate 3 - Fig. 6). The spores of the living species are usually semicircular in equatorial view but those of fossil species could not usually be seen due to compression. The perispores of living species are very developed and strongly sculptured. Most of the perispores are sculptured by irregular tubercles, papillae, granulate deposits or ridges, and some genera such as Cystodium, Dicksonia and Thyrsopteris have even two or more layers of perispores (Tryon and Lugardon 1991). Furthermore, studies also show that the perispores of the extant species are gradually developed as the spores mature. The more mature the spores, the stronger the sculpture of the perispores. For instance, the unripe spores of Cystodium sorbifolium have slightly sculptured perispores that are covered with lines and stripes, but the ripe spores are

covered by a perispore sculptured by granulate deposits (Tryon and Lugardon 1991). The perispores of the fossil spores are rarely seen due to a long geological history and the treatment undergone in the laboratory. According to Gastony (1981 1982), the fully developed spores are very different to those preserved in situ on the leaf. Therefore, we suggest that the fossil spores in situ should chiefly be unripe or nearly ripe. The exines of the spores of the living dicksoniaceous ferns are mainly smooth except for a very few species that have fine grains, showing similarities to the fossil types. An interesting character of the living species is that the spores have thickened parts along the laesurae. This structure is described as a "mago" under the light microscope. It is occasionally observed in the in situ spores of the Mesozoic dicksoniaceous ferns, but is frequently seen in dispersed spores from Jurassic and Cretaceous sediments. Another sculpture feature of the spores of the living species is that there are usually pits or puncta on the exines arranged along the laesurae. This structure could not be destroyed by an alkali solution such as NaOH and can be easily observed under SEM. Therefore, Gastony (1982) suggested it would be significant for fossil identification. Truly, Coniopteris simplex and Dicksonia kendalliae of the Yorkshire (Van Konijnenburg-van Cittert 1989), Coniopteris hymenophylloides and Eboracia lobifolia from the Jurassic of Western China, and Coniopteris vacharameevii of Early Cretaceous of Northeast China have this structure. Gastony (1982) also found that this structure is developed on maturity, and usually not at the beginning of development. The laesurae of the living species are usually shown as straight lines, mostly as a ridge and are sometimes groove-like or crack-like (Fig. 25 in Gastony 1981), close to the fossils. The length of the laesurae is usually only 2/3 to 3/4 of the radius, but the fossils are up to 3/4-7/8. The distributions of the extant dicksoniaceous ferns are very different from the Mesozoic types. The former are chiefly distributed in the tropics and partly in the subtropics with a few in temperate zones (Copeland 1947, Holttum 1963, Roy and Holttum 1965, Gastony 1981 1982), mostly in the Southern Hemisphere; while the latter are globally distributed, and mostly in temperate zones (warm and humid climate) of the Northern Hemisphere (see below in detail).

THE DISTRIBUTION OF THE MESOZOIC DICKSONIACEAE

Early Jurassic The Dicksoniaceae possibly first appeared in the beginning of the Early Jurassic and gradually developed during the latter part of the Early Jurassic. Definitely the oldest Coniopteris was possibly reported from two localities in China based on both the sterile and fertile material (Plate 1 - Fig. 7). One is Hunan of South China (Feng et al. 1977, Zhang 1982 1985, Zhou 1984); the other one is the Junggar basin of Xinjiang of Northwest China (Deng et al. 2000). Other similar fossils were reported from the Turupan-Hami basin (Coniopteris cf. hymenophylloides; Wu and Zhou 1986), and the Prisbachian of Japan (Coniopteris neiridaniensis; Kimura and Tsujii 1980, Kimura 1987). The dicksoniaceous ferns have been more widely distributed in the late Early Jurassic. However, only a few

species of Coniopteris occurred, and Eboracia was only occasionally recorded. During the Toarcian, since there was a big transgression in the European continent, the terrestrial sediments were poorly developed with a very limitedly distributed there, and few plant fossils have been found from age-old sediments. The only possible record of a dicksoniaceous fern, Coniopteris sp., is from the Herzegovina area (Pantic 1981). In Central Asia, materials assigned to Coniopteris hymenophylloides or C. er.gr. hymenophylloides had been frequently reported from the late Early Jurassic of several localities, such as North Caucasus (Vachrameev and Vasina 1959), Northern Iran (Barnard 1965 1967), Tuarkyr (Burakova 1963), Mangyshlak (see Vachrameev 1964 1991) and Darvaz (Luchnilov 1967). In Siberia, the floras of the late Early Jurassic are quite developed, in which one or two species of Coniopteris occurred (Vachrameev 1961, Vachrameev et al. 1988). However, no Coniopteris has been recorded yet from the flora of the middle reaches area of the Kolyma River, which is attributed to the Toarcian by ammonites. The possible late Early Jurassic floras in China are widely developed. As there are no marine fossils to control the age, the floras of China can not be exactly dated. Usually, each flora has 1-2 species of Coniopteris. The late Early Jurassic floras in China can be approximately subdivided into north and south types. The north type is represented by the Sangonghe plant assemblage in North Xinjiang of Northwest China, the south type by the Xiangxi Flora of Hubei Province (Wu et al. 1980). Other north type floras include the floras from the Yangxia Formation of the Tarim basin, South Xinjiang (Wu 1985), the Fuxian Formation of the Ordos basin (Huang and Zhou 1980), the Yongdingzhuan Formation of the Datong basin, Shanxi (Li and Hu 1984), the Lianjiashan Formation of Hebei (Wang 1984), and the Beipiao Formation of western Liaoning (Mi et al. 1996). In the Sangonghe assemblage, the dicksoniaceous ferns have been represented by Coniopteris simplex, C. cf. hymenophylloides and C. sp. (Plate 1 - Figs. 5, 6). In the Xianxi Flora, there are Coniopteris cf. hymenophylloides, C. cf. bella and C. cf. murrayana (Wu et al. 1980), but the age of this flora was regarded as being the latter part of the Early Jurassic to early Middle Jurassic. The other south type floras have been reported from Hunan, Hubei, central China (Zhou 1984 1995, Feng et al. 1977, Huang and Zhou 1980, Zhang 1982 1985, Li and Hu 1984, Li et al. 1988, Huang 1983 2001, Wu 1985, Huang and Lu 1988, Huang and Qi 1991, Mi et al. 1996, Xu 1996, Huang et al. 1998, Shenghui and Fen 2000). Almost no dicksoniaceous ferns have been reported from the Early Jurassic of other areas besides Europe and Asia. Coniopteris arguta and C. cf. hymenophylloides and even Gonatosorus have been reported from southern Mexico. However, the age of the sediments bearing these ferns ranged from the Early to Middle Jurassic (Silva-Pineda 1970 1978). This flora does not seem to belong to the Early Jurassic. The Middle Jurassic The Middle Jurassic is the first flourishing period of the dicksoniaceous ferns. Obviously, they were distributed worldwide but mostly in Northern Hemisphere, particularly in Eurasia (Table 5; Fig. 3). According to Vachrameev (1991), there are four phytogeographic realms during the Jurassic and Cretaceous. They are the Siberia-Canadian realm, Euro-Chinese

realm, Australian realm and Equatorial realm. The Jurassic Dicksoniaceous ferns are mostly distributed in Siberia-Canadian and Euro-Chinese realms, especially in Central Asia and North China. The "North China" here means the north area bounded by the Kunlun-Qinling-Dabie Mountains. The Middle Jurassic floras are very developed, and are dominated by ferns, gingkoes and conifers, especially the dicksoniaceous ferns. Coniopteris is extremely abundant, with a total of about 20 species (Table 5). Others include some Eboracia, Gonatosorus and Dicksonia, but no Kylikipteris have been recorded. These ferns usually occupied 5-10% and even to 17% of the total floral content (Table 6). The Euro-China phytogeographic realm includes most parts of Europe, Greenland, Central Asia, south China and the Outer Zone of Japan (Vachrameev et al. 1988, Vachrameev 1991). Central Asia, incorporating the Fergana basin (Brick 1953), Karatau of Kazakstan (Doludenko and Orlovskiaya 1976), Tajikistan (Luchnikov 1982) and Jissar (Vachrameev 1991), Tuarkyr of Turkmenistan (Burakova 1963) and also the adjacent Xinjiang, Qinghai and Gansu of Northwest China (Sun 1986, Li et al. 1988, Shang et al. 1999), is possibly the distribution center of the dicksoniaceous ferns during the Middle Jurassic, with 10 or more species in every flora. The Yorkshire Jurassic Flora of England is the representative flora, which has 10 species (Table 5). Six species of Coniopteris, two Dicksonia and one Kylikipteris have been described (Harris 1961). In South China, the typical Middle Jurassic sediments are usually characterized by red coloured rocks, and usually with few plant fossils. A floral assemblage Todites princeps-Ptilophyllum (Zhou 1995) is roughly assigned to the Early-Middle Jurassic, in which 2-5 species of Coniopteris have been recorded (Yang 1987, Zhou 1995, Meng and Chen 1997, Huang et al. 1998, Meng 1999, Huang 2001). The common species are Coniopteris hymenophylloides, C. burejensis and C. murrayina. The Early-Middle Jurassic flora in South China is characterized by dipteridaceous and osmundaceous ferns and bennetitales such as Ptilophyllum and Otozamites, and relatively fewer ginkgoes, especially Ginkgoites. It is obvious that the Dicksoniaceae are much fewer in South China than in North China. In the Australian phytogeographical realm, dicksoniaceous fossils have been reported from Queensland (Hill et al. 1968) and the south end of the North Island, New Zealand (Mildenhall 1970). But only one or two species are found. There are records of Coniopteris and Dicksonia from India as well, however the exact ages reminded unknown (Shah 1977). Some fossils assigned to Coniopteris hymenophylloides and C. lobata were once reported from Graham Land of the Antarctica (Halle 1913), but the age is problematic, possibly the Middle Jurassic but also possibly the Late Jurassic. The Jurassic floras declined very much from the Bathonian of Middle Jurassic. In China, the dicksoniaceous ferns were reduced as was the flora from the Late of the Middle Jurassic. The Upper of the Middle Jurassic in South China is dominated by red coloured or purple sediments, with almost no plant fossils recorded. In contrast, in North China, the formations are characterized by gray or green coloured lacustrine sediments, yielding small

Fig. 3 The distribution of the Middle Jurassic dicksoniaceous ferns. 1. Japan (Kimura and Ohana 1987), 2. West Liaoning, NE China (Mi et al. 1996, Zhang and Zheng 1987), 3. West Beijing, N China (Chen et al. 1984, Duan 1987), 4. Ordos basin NW China (Huang and Zhou 1980), 5. Yima Basin N. China (Deng et al. 2003), 6. Northeast Sichuan, SW China (Ye et al. 1986, Meng and Chen 1997), 7. Zhejiang, SE. China (Huang 1991), 8. South Sichuan, SW China (Yang 1987), 9. Minhe of Gansu, NW China (Sun 1986), 10. Qiadam basin, NW China (Li et al. 1988), 11. Turupan-Hami basin, NW China (Shang et al. 1999), 12. Junggar basin, NW China (Deng et al. 2003), 13. Fergana basin (Brick 1953), 14. Karatau, Kazakstan (Doludenko and Orlovskiaya 1976), 15. Middle Tajikistan (Luchnikov 1982), 16. Jissar (Vachrameev 1991), 17. Tuarkyr, Turkmenistan (Burakova 1963), 18. Mangyshlak, Kazakstan (Vachrameev 1964 1991), 19. Transcaucasia, Georgia (Dalle 1967), 20. Yorkshire, England (Harris 1961), 21. Oregon of United State (Fontaine 1905), 22. South of Mexico (Silva-Pineda 1984), 23. Queensland, Australia (Hill et al. 1968), 24. New Zealand (Mildenhall 1970).

Table 5 The distribution of the dicksoniceous ferns in the Middle Jurassic. cf. =cconformis Areas Northeast Sichuan, SW China Minhe of Gansu, NW China

Turupan Basin, NW China

Junggar Basin, NW China

Qiadam Basin, NW China

South Sichuan, SW China

West Liaoning, NE China

Queensland, E Australia

cf.

Mangyshlak, Kazakstan

Tuarkyr, Turkmenistan

West Beijing, N China

Ordos Basin, N China

Yima Basin, N China

Karatau, Kazakstan

Zhejiang, SE China

Yorkshire, England

Middle Tajikistan

South of Mexico

Fergana Basin,

New Zhiland

Species Coniopteris angustifolia C. arguta C. beijingensis C. bella C. burejensis C. datungensis C. dilicatula C. dujiaensis C. embensis C. ferganensis C. furssekioi C. hymenophylloides C. jagmanica C. kumbelensis C. lanzhouensis C. lobata C. latifolia C. macrosorata

cf. cf.

cf.

cf.

cf.

cf

Antarctica

Japan

Jissar

Table 5 (cont.)

C. margaretae C. minturensis C. murrayana C. nervifolia C. nympharum C. porcina C. pulcherrima C. qinghaiensis C. rara C. simplex C. sewardi C. spectabilis C. szeiana C. spectabilis var. lucata C. tiehshanensis C. tyrmica C. vialovii C. yongxiaensis C. zhenziensis C. zindanensis Coniopteris sp. Dicksonia charieisa D. hangheyingziensis D. kendalli D. mariopteris Eboracia lobifolia Gonatosorus dameigouensis G. lobifolius G. nathorstii G. sphenopteroides G. simplex Kylikipteris arguata

?

cf.

cf.

Table 6 The percentages of the dicksoniaceous ferns in some Middle Jurassic floras of China. Locality West Beijing, N China Beipiao of Liaoning, NE China Qiadam basin, NW China Yima basin, N China Turupan-Hami basin, NW China Minhe basin, NW China Number of dicksoniaceous species 5 6 9 7 8 8 Percentage of the flora (%) 6.8 10.9 7.8 17 8.7 14.7 Reference Chen et al. 1984 Mi et al. 1996 Li et al. 1988 Deng et al. 2003 Shang et al. 1999 Sun 1996

floras. The most abundant one is the Lanqi flora from western Liaoning Province, Northeast China (Zhang and Zheng 1987), which is composed of 76 species. The Dicksoniaceae are represented by Dicksonia changheyingziensis, D. charieisa, Coniopteris burejensis, C. hymenophylloides, C. tyrmica, and Eboracia lobifolia. Another example is the flora from the Yabula basin of Western Mei Mongol (Deng et al. 2004), which consists of only 12 species, dominated by Beenettitales. Three species of Coniopteris: C. hymenophylloides, C. cf. burejensis, C. angustiloba were found. Other Bathonian floras in North China have been reported from the Qiadam basin of Qinghai Province (Li et al. 1988), Jingyuan of Gansu Province (Xu 1986), the Ordos basin of Shaanxi Province (Yuan et al. 2003), which have two, three and four species of dicksoniaceous ferns respectively. Although it is difficult to determine the exact geological ages due to absence of marine fossils, the formations yielding those plant fossils could roughly be assigned to the Bathonian to Callovian (Deng et al. 2003). The floras of the late Middle Jurassic in Europe are much reduced as well. In the Upper Delta of Yorkshire, the flora is composed of about 20 species, including one dicksoniaceous fern Coniopteris hymenophylloides (Harris 1961). In France, the Bathonian flora is represented by many Otozamites, but no

Coniopteris occurred. In West and Central Asia, usually one or two species of Coniopteris occurred in the Bathonian floras of Georgia (Dalle 1967), Ukraine (Vachrameev 1964), Jissar (Vachrameev 1991), Tajikistan (Luchnikov 1973 1982). But Fergana is an exceptional example, in which 6 species of Coniopteris have been recorded in the Zindan Formation, although the total number of species of the flora is only half as many as the underling beds (Genkina 1977 1979). Late Jurassic The Jurassic floras were greatly reduced in the Late Jurassic due to the arid climate. Evaporites sediments were extensively developed in the world, such as Central Asia, North America, Northwest and South China. Most of the Southern Hemisphere was denuded lands. The floras were restrictedly distributed in some areas, such as Siberia and Northeastern China. In Siberia, the floras are similar to those of the Middle Jurassic, consisting of ferns, ginkgoales, Czekanowskiales and conifers. Usually, 1-3 species of Dicksoniaceae have been recorded from the Upper Jurassic of the Lena basin (Vachrameev 1985, Kiritchkova 1976 1985), the Yakutiya basin (Vlassov and Markovich 1979a 1979b), the Bureja basin (Vachrameev and Doludenko 1961, Krassilov 1978), and the Zeya basin (Lebedev 1965). The

species include Coniopteris burejensis, C. ex gr. hymenophylloides, C. tyrmica, C. sewardii and Eboracia lobifolia and E. kataevensis. In China definite Late Jurassic plants were very rarely found. Coniopteris hymenophylloides and C. tatungensis were reported from the possible Upper Jurassic sediments of the Northern Hebei and Western Liaoning Provinces. The Late Jurassic flora from Southwest Madagascar (Appert 1973) is quite abundant, in which the ferns are highly diverse, including Schizaeaceae, Gleicheniaceae, Matoniaceae, Dicksoniaceae and possible Dipteridaceae. The Dicksoniaceae include Coniopteris manamanensis, Culcitites madagascariensis, Eboracia lobifolia and Haydenia thyrsopteroides. But some of the identifications are possibly problematic. For example, the fertile fronds assigned to Eboracia lobifolia have only one sorus in each pinnule, which is very different from the typical middle Jurassic materials (Harris 1961; Plate 1 - Fig. 9 in this paper). There are also some Early Cretaceous species such as Ruffordia goepperti and Onychiopsis psilotoides in the flora. Therefore, the age of the flora seems to need further study. Some small floras of the Late Jurassic have been described from Scotland and Portugal (Teixera and Pais 1976), France, Germany (Barale 1970 1981), Poland (Doludenko 1984) and the Caucasus area (Doludenko and Svanidze 1969), but almost no dicksoniaceous ferns have been reported. The Early Cretaceous Compared with the Jurassic, the distribution of the Dicksoniaceae in the Early Cretaceous is rather different. They were mostly restricted to temperate areas, i.e. the

Siberia-Canadian Phytogeographic realm, including Siberia, Northeast China, and the Inner Zone of Japan (Fig. 4). Usually with about 5-10 species of the dicksoniaceous ferns, which occupy about 10% of the flora (Table 7; Fig. 4). In China, Dicksoniaceae are chiefly distributed in Northeast China and some in North China. Four species of Coniopteris, two of Dicksonia and one of Acanthopteris of the Hailar Flora of Inner Mongolia (Nei Mongol) have been recorded (Deng et al. 1997); seven species of these ferns in the Huolinhe Flora of Inner Mongolia (Nei Mongol; Deng 1995), six species in the Fuxin Flora of western Liaoning (Chen et al. 1988); about eight species from the Chengzihe Formation (Zheng and Zhang 1982). In contrast, only very few doubtable Coniopteris species have been recorded in the Europe-China Phytogeographic realm, including Europe, Central Asia, South and Northwest China, and the United States. No dicksoniaceous ferns have been found from the European Welden floras until recent years, when Coniopteris sp. was reported by Watson et al. (1996) from England and Coniopteris laciniata recorded by Dieguez and Melendez (2000) from Spain, although they have been studied for more than one hundred years (Seward 1894 1913). In Southeast China, almost none of these ferns have been found (Chow 1923, Cao 1995) except for a few uncertain species that have been reported from Zhejiang (Cao 1999), where the floras are dominated by Cycads, Bennetitales, comparable with the England Welden flora. Dicksoniaceous ferns are absent from the Lower Cretaceous sediments of a huge area from Tibet in Southwest China (Duan et al. 1977, Li 1982, Li and Wu 1991) to Central Asia, south of the United States, South America, Australia and Africa. The only report from Central America is

Fig. 4 Distribution of the Early Cretaceous dicksoniaceous ferns. 1. Omusukchana basin, Russia (Samylina 1976), 2. Zyrianka basin, Russia (Samylina 1963), 3. Lena basin, Russia (Vassilevskaja 1963), 4. Aldan basin, Russia (Samylina 1963), 5. Sakhalin Island (Krassilov 1979), 6. Bureja basin, Russia (Vachrameev and Doludenko 1961), 7. South Primorie, Russia (Krassilov 1967), 8. Hailar basin, NE China (Deng et al. 1997), 9. Sanjiang basin (Cao 1992), 10. Jixi basin (Zheng and Zhang 1982), 11. Shansong, Jilin (Li et al. 1986), 12. Tiefa basin (Chen et al. 1988, Deng 1992), 13. Huolinhe basin, NE China (Deng 1995), 14. Fuxin basin, NE China (Chen et al. 1988), 15. Pingzhuang-Yuanbaoshan, NE China (Deng 1998), 16. Pingquan, Hebei Province (Chen and Yang 1982), 17. Guyang basin, North China (Tan and Zhu 1982), 18. Huicheng basin (Xu 1986), 19. Nanzhao (Wu 1993), 20. Zhejiang (Cao 1999), 21. Inner Zone of Japan (Kimura 1987), 22. Outer Zone of Japan (Kimura 1987), 23. Wealden of England (Watson and Alvin 1996), 24. Spain (Diéguez and Meléndez 2000), 25. Western Canada (Bell 1956), 26. Montana, NW USA (Lapasha and Miller 1984), 27. Columbia (Lemoigne 1984).

that of Coniopteris martinezi from Columbia (Lemoigne 1984), belonging to the equatorial phytogeographical realm

(Vachrameev 1991).

Table 7 The distribution of the dicksoniaceous ferns in the Early Cretaceous. cf. =cconformis; aff. = affinis; ex gr. = ex grege. Areas Pingzhuang-Yuanbaoshan, NE China

Guyang basin, North China

Huicheng Basin, NW China

Shansong, Jilin, NE China

Huolinhe basin, NE China

Sanjiang Basin, NE China

South Primorie, Russia

Zyrianka basin, Russia

Fuxin basin, NE China

Omusukchana, Russia

Tiefa basin, NE China

Jixi Basin, NE China

Inner Zone of Japan

Zhejiang, SE China

cf. cf. cf. ?

Lena River, Russia

Out Zone of Japan

Hailaer, NE China

Species

Coniopteris arctica C. burejensis C. bicrenata C. brevifolia C. berryi C. chankaensis C. compressa C. concinna, C. densivenata C. dicksonioides C. ermolaevii, C. gracillima C. gleichenioides C. huolinheensis C. kolymensis C. laciniata C. longipinnata C. maakina C. martinezi C. nerifolia, C. nympharum, C. onychioides C. saportana, C. setacea, C. vachrameevii, C. venusta C. vsevolodii, C. yukonensis Coniopteris sp. Acanthopteris gothani Dicksonia ishikawaensis D. maniyai D. silapensis, Dicksonia sp. Eoracia microlobifolia E. ishikawaensis E. nipponica E. tetoriensis Gonatosorus katovae

cf.

aff. ex gr. cf. cf. cf. cf. cf.

ORIGIN AND EVOLUTIONARY TRENDS OF THE DICKSONIACEAE

The aspects of the origin and evolutionary trends of the Dicksoniaceae are still problematic due to incomplete fossil records and unsatisfactory studies. The original time and place and some aspects of the evolution trends may be roughly discussed based on the present data as follows.

Original time and place of the Dicksoniaceae The original time of the Dicksoniaceae could be indicated by the records of the oldest fossils. The most reliable and oldest dicksoniaceous fossils (Coniopteris) have not been found from the Early Lias floras of Greenland (Harris 1931 1937), North Italy (Wesley 1956), France (Depape 1961), Poland (Reymanowna 1963), Germany (Gothan 1935), Iran (Boureau et al. 1950) and Darvaz of Central Asia (Luchnikov 19671).

Nanzhao, N China

Wealden, England

Western Canada

Sakhalin Island

Bureja, Russia

Aldan, Russia

Columbia

Spain

However, Coniopteris was usually represented by one or two species in the late Early Jurassic floras of many localities, such as the Toarcian floras in the Montenegro area of the former Yugoslav (Pantic 1981), the Late Lias floras of Poland (see Vachrameev 1991), Romania (Popa 1998), Iran (Barnard 1965 1967), the Caucasus area (Vachrameev and Vasina 1959), Tuarkyr (Burakova 1963), Mangeshelak (see Vachrameev 2001), the Zaysan basin of Kazakstan (Turutanova-ketova 1962), the Siberia region including the Irkutsk, Kolyma and Vilui basins (Vachrameev 1958 1961 1991). Therefore, the appearance of Coniopteris was sometimes considered as the mark of the Lias age (Vachrameev 1991). In China, definitely the oldest Coniopteris materials with fertile fronds have been collected from the early Early Jurassic strata, from the Gaojiatian Formation of western Hunan Province (Feng et al. 1977, Zhang 1982 1985) and the middle-lower part of the Guanyintan Formation of southern Hunan Province, South China (Zhou 1984). The Paijiachong member of the Guanyintan Formation, containing Coniopteris microlepioides is assigned to the Hettangian of the Early Jurassic (Zhou 1984), and the overlying Tabakou member, yielding Coniopteris gaojiatianensis and C. microlepioides, possibly represent the Sinemurian-Plinspachian (Zhou 1984). Coniopteris gaojiatianensis has also been recorded in the middle members of the Badaowan Formation of the Junggar basin, Xinjiang, Northwest China (Deng et al. 2000). The age of the Badaowan Formation is considered to be about the Hettangian to Sinemurian of the Early Jurassic (Deng et al. 2003, Zhang et al. 2003) based on conchastracans, bivalves, sporopollen and megaplants. Some similar fossils from the basal bed of the Badaowan Formation, Turpan-Hami basin, Xinjiang had been attributed to Coniopteris cf. hymenophylloides. This species is associated with abundant Dipteridaceae and Matoniaceae ferns and Cycadocarpidium, and was suggested to be the early of the Early Jurassic (Wu and Zhou 1986). However, due to the lack of fertile frond evidences, Coniopteris cf. hymenophylloides is doubtful (Zhou 1995). These records of Coniopteris in China indicate that the dicksoniaceous ferns definitely appeared in the early of the Early Jurassic, and means that the origin time of the Dicksoniaceae is early Early Jurassic and the original place may be China or Eastern Asia. Characters of the early dicksoniaceous ferns and their adaptation The early dicksoniaceous ferns are small and weak plants. Coniopteris fossils from the Lower Jurassic are characterized by their small size, slender rachis and small fronds and pinnules. Coniopteris gaojiatianensis is characterized by its 1-2 cm long penultimate pinnae and 1-2 mm long pinnules (Feng et al. 1977, Zhou 1984, Deng et al. 2003; Plate 1 - Fig. 7). Similarly, the pinnules of another Early Jurassic C. microlepioides are less than 2 mm long and 1 mm wide (Zhou 1984). The specimens of Coniopteris cf. hymenophylloides, C. cf. murrayana and C. sp. from the Xiangxi Formation of western Hubei Province (Wu et al. 1980) and Coniopteris cf. bella, C. cf. nerifolia, C. tiehshanensis and C. sp. from the Lower Jurassic Zhenzhuchong Formation (Ye et al. 1986) have also very small pinnules as do the so-called Coniopteris cf. hymenophylloides from the Lower Jurassic Fuxian Formation of Ordos (Shaanxi-Gansu-Ningxia) basin (Huang and Zhou 1980) and Coniopteris

hymenophylloides of the Lower Jurassic Yongdingzhuang Formation of the Datong basin of Shanxi Province (Li and Hu 1984). The small sized body, slender rachis and small pinnules show that the early dicksoniaceous ferns are puny plants with limited competitive ability. Another marked character of the early dicksoniaceous ferns is that most of them have relatively larger sori. C. gaojiatianensis has sori of about 1.2-1.5 mm long and 0.5-0.7 mm high (Zhou 1984), being quite large in comparison to its smaller fronds. Similarly, C. microlepioides has sori of 1-1.3 mm long and 0.7-0.8 mm wide (Zhou 1984). Coniopteris gansuensis from the Qingtujing Group of Gansu has very large sori of more than 2 mm in diameter (Cao and Zhang 1996). The specimens of Coniopteris sp. from the Sangonghe Formation of Junggar basin (Plate 1 - Fig. 5) and Turupan-Hami basin (Plate 1 - Fig. 6), Xinjiang, which is the Prisbachian-Toarcian age (Deng et al. 2000 2003) show its large sori to be over 2 mm in diameter. The large sori should be an adaptive response to their lower competitive ability, because larger sori may generate a greater number of spores. The structures of the Early Jurassic Coniopteris have been poorly understood, the sporangium, spore and the spore output remain to be investigated. Therefore, the early dicksoniaceous ferns, especially those from the beginning of the Early Jurassic are delicate plants. The plants of Dicksoniaceae became gradually stronger in time, and towards the end of the Early Jurassic some species close to Coniopteris hymenophylloides, which flourished in the middle Jurassic appeared (Wu et al. 1980, Ye et al. 1986). The larger sori are possibly a guarantee of high competitive ability. The evolutionary trend in morphology The evolutionary trends of the Mesozoic dicksoniaceous ferns are more obvious in the fertile parts than in the sterile parts. As mentioned above, the early Dicksoniaceae are represented by smaller and weaker species in the early Early Jurassic and by relatively larger and stronger types in the latter part of the Early Jurassic. During the Middle Jurassic and Early Cretaceous, the family was dominated by larger size species such as Coniopteris hymenophylloides of the Middle Jurassic (Harris 1961) and Acanthopteris gothani of the Early Cretaceous (Deng and Chen 2001). These species are over 100 cm tall. Naturally-occurring small size types such as Coniopteris simplex of the Middle Jurassic (Plate 1 - Figs. 3, 4, 8) and Coniopteris setacea of the Early Cretaceous (Plate 3 - Fig. 4), which were around 20 cm high existed as well. But no evidence shows that there was any tree fern of this family in the Mesozoic, though the living Dicksoniaceae are tree ferns or tree-like ferns (Copeland 1947, Wu and Ching 1991, Tryon and Tryon 1982). The evolutionary pattern from Mesozoic herbaceous plants to the living tree fern lacks evidence. The first pinnules of the basiscopic side of some Jurassic species are divided into linear lobes. This character is gradually developed from the Early to Middle Jurassic and disappeared in the Early Cretaceous. The early Early Jurassic species did not divide, while the late Early Jurassic species were slightly lobed. In contrast some species of the Middle Jurassic had very developed first abnormal basal pinnules, such as Coniopteris hymenophylloides (Plate 1 - Figs. 2, 12, 13), C. bella (Harris 1961) and Eboracia lobifolia (Plate 1 - Fig. 1). We found some

materials even had both basiscopic and acroscopic abnormal basal pinnules. However, no abnormal pinnules were found in the Early Cretaceous species, instead of marked intercalated pinnules in some species, such as Acanthopteris gothani (Plate 2 - Figs. 1, 2; Plate 3 - Fig. 1) and Coniopteris silapensis (Plate 4 - Fig. 1). The fossil plants characterized by intercalated pinnules usually have narrower vertical ranges in stratigraphy and were suggested to have been implicated in extinction (Sze 1954). The evolutionary trends of the reproductive organs of the dicksoniaceous ferns are shown by the size of sporangia, spores, length of laesurae, and sculptures of the exines. The sporangia of the Jurassic species are usually more than 200 m such as that of Coniopteris hymenophylloides which are up to 250×400 m (Harris 1961). But the Early Cretaceous species usually have sporangia of 150×200 m in size. Generally, the Jurassic species have larger spores than the Cretaceous ones. The average size of the Jurassic species are about 40-50 m in diameter, and the maximum average size is up to 74 m (Table 1 ) and some the biggest spores even measured up to 97 m in diameter (Harris 1961). The Early Cretaceous species seem to having slightly smaller sized spores. Most of the Cretaceous species have spores of 35-40 m, with only a few species over 40 m in diameter (Table 2). The biggest spores are about 65 m, much smaller those of Jurassic species. The living Dicksoniaceae have spores of usually 28-40 m in diameter (Gastony 1981 1982) although a much larger number have been obtained when the spores were measured with perispores (Table 3). Therefore, the sizes of the spores of the Dicksoniaceae became smaller and smaller along geological history. As mentioned above the Jurassic species of the Yorkshire flora have finely granular or pitted spores though Van Konijnenburg-van Cittert (1989) believed these spores should have perispores. But, the Lower Cretaceous elements usually have smooth surfaces, except for a few species, such as Acanthopteris gothani and Dicksonia silapensis which have very small (0.5-1 m) size granules (Plate 4 - Fig. 4). Similarly, the exines of the spores of the extant dicksoniaceous ferns are mainly smooth or with fine granules although their perispores are complexed sculptured. Therefore, it seems that simplification of the exines is also one of the evolutionary trends. The laesurae of the living species are usually 2/3-3/4 of the radius in length, but the fossils are in general 3/4-7/8 (Van Konijnenburg-van Cittert 1989, Deng and Chen 2001). Shortening of the laesurae is possible an evolutionary trend. It seems that there are no marked changes in morphology of the annuli and the spore number per sporangium. The macro evolution of the Mesozoic Dicksoniaceae The dicksoniaceous ferns have experienced two evolutionary peaks during the Mesozoic. Before the first flourishing period, the Dicksoniaceae family slowly developed after its origin in the early Early Jurassic. The family is represented by only several species of Coniopteris at the beginning, having a relatively small distribution in China (Zhang 1982 1985, Zhou 1984, Deng et al. 2000). These ferns survived the early Toarcian temperature raising event (Vachrameev 1991) and then extensively and rapidly developed when the temperature dropped in the middle Toarcian. They successfully expanded to Siberia, Central Asia,

Europe and even North America. However, they are still represented by several species, which occupied a very small position in the floras. The first peak of the development appeared in the Middle Jurassic after gradually developing in the beginning of the Early Jurassic. They are abundant, of great variety and distributed almost worldwide (Fig. 3). Almost 50 species belonging to Coniopteris, Dicksonia, Eboracia, Gonatosorus and Kylikipteris have been reported (Table 5). The common elements are Coniopteris hymenophylloides, C. burejensis, C. bella, C. tatungensis and Eboracia lobifolia. In most of the Middle Jurassic floras, the dicksoniaceous ferns are represented by several species to more than 10 species, accounting for about 5-10% of some Chinese floras (Table 6). After the Bathonian of the Middle Jurassic, the temperature rose and the climate was arid, the dicksoniaceous ferns declined, with a great reduction in the number of species. Up to the Late Jurassic, most of the species went extinct. Only few species had survived and were restricted to Siberia (Vachrameev and Doludenko 1961) and Northeast China, where it was relatively more humid and warmer. Along with the globular temperature dropping in the end of the Jurassic and the begining of the Cretaceous, the humid-warm climate zone expanded southwards, and the Dicksoniaceae gradually recovered. The Jahol flora of the early Early Cretaceous of Northeast China, as an example, has 2-3 species of Coniopteris (Wu 1999, Sun et al. 2001). The Dicksoniaceae achieved their second flourished episode in the Early Cretaceous (particular the Barremian stage) after a rapid development in the beginning of the Cretaceous. In this episode, the Dicksoniaceae exhibited a great increase in diversity, especially the species diversity of Coniopteris. A total of about 40 species belonging to Coniopteris, Dicksonia, Gonatosorus and Eboracia have been reported (Table 7). As mentioned above, the distribution of the Early Cretaceous dicksoniaceous ferns are different from that of the Jurassic. They have a distribution center in the temperate climatic areas that includes Siberia and Northeast China of the Siberia-Canada Phytogeographic realm. The dicksoniaceous ferns usually dominate the fern group of the flora. Only a fewer species were reported from the subtropics and tropic areas (Fig. 4). Almost all the known species went extinct after the Early Cretaceous due to the frequent changes of calamite. Records of the Late Cretaceous and Cenozoic Dicksoniaceous are very few. Dicksonia dissectia (Jordan et al. 1996) is an example from the Oligocene of the Tertiary. The extant Dicksoniaceae with about 40 species belonging to 5-6 genera occupy a very small percentage of the living Filicopsida. They are very different from their flourished state during the Middle Jurassic and Early Cretaceous. All the extant dicksoniaceous ferns are tree ferns or tree-like ferns and restricted to the tropics and south of the sub-tropic zones. The relation between the fossil dicksoniaceous ferns and the living Dicksoniaceae still remains a puzzle.

SIGNIFICANCES FOR STRATIGRAPHIC CORRELATION

The Mesozoic dicksoniaceous ferns are very significant in

continental Mesozoic stratigraphic division and correlation. As the reliable Coniopteris was firstly found in Early Jurassic, therefore the appearance of Coniopteris could indicate Early Jurassic or younger ages. Coniopteris characterized by small fronds with a weak rachis may show a Lias period. Most of the species are widely distributed but with a narrow stratigraphic range. Coniopteris hymenophylloides is usually considered as a middle Jurassic plant which is extensively distributed. The appearance of Coniopteris hymenophylloides, especially when associated with Coniopteris burejensis and Eboracia lobifolia can indicate the beginning of the Middle Jurassic age. Acanthopteris gothani, Coniopteris setacea, C. longipinnata, C. huolinheensis, C. ermolaevii and Dicksonia silapensis represent Early Cretaceous age.

ACKNOWLEDGMENTS

We thank Dr. Eugenia Bugdaeva of the Institute of Biology and Soil Sciences of the Far East Branch of the Russian Academy of Sciences for her kind help in Russian references and Mr. Zhang Wanpeng form the China University of Geosciences for his help in plate preparation. This work was supported by the NSFC (Grant number: 40372021).

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Scientific summary (January 2006 ­ April 2006)

by Jaime A. Teixeira da Silva Due to time, space and energy constraints, experiments relating to very basic results, unless presenting significant findings, are not presented in GPL, even if those results have pertained to ornamentals. GSB extends a heart-felt apology if any relevant result has been omitted, and warmly invites readers to fill that information gap by submitting those results/findings to [email protected] for possible inclusion in a forthcoming Issue. Results have been compiled and presented in alphabetic order according to broad themes, some of which may overlap. Presented results are not meant to be a thorough review on a topic, but rather a "flash" presentation of research highlights.

Acid rain and acid snow Acid rain is made up of sulfur dioxide (SO2) and nitrogen oxides (NOx), produced by power stations and exhaust fumes. The oxidation of these two components in rain clouds is catalyzed by the presence of iron, manganese, ammonia, and hydrogen peroxide (H2O2). Simulated acid rain (SiAR) has negative effects on several Arabidopsis growth parameters (total biomass, shoot height, root length, leaf area), when applied at different stages of development (Lee et al. 2003). Leaf necrotic legions developed in response to SiAR, particularly sulphuric SiAR, activating the salicylic acid pathway (Lee et al. 2006), another stress-induced pathway. Inada et al. (2006) studied acid snow, proving that it might be an environmental stress factor for wintering plants.

Inada H, Nagao M, Fujikawa S, Arakawa K (2006) Influence of simulated acid snow stress on leaf tissue of wintering herbaceous plants. Plant and Cell Physiology 47, 504-512 Lee S, Park J, Park J (2003) Effects of simulated sulfuric and nitric acid rain on growth and seed germination of Arabidopsis thaliana. Journal of Environmental Science (China) 12, 659-664 Lee Y, Park J, Lim K, Kim K, Lee J, Lee K, Park J-A, Lee T-K, Park D-S, Yang J-S, Kim D, Lee S (2006) Arabidopsis leaf necrosis caused by simulated acid rain is related to the salicylic acid signaling pathway. Plant Physiology and Biochemistry 44, 38-42

Annexins, extensins and prohibitins Annexins ­ localized at the cell periphery of secretory cell types, but also occurring in the cytoplasm, the vacuole and nucleus ­ are one group of calcium-binding proteins that transduce calcium signals into adaptive responses during growth and development, perhaps by playing a role in the Golgi-mediated secretion of new wall materials and plasma membrane that occurs during these physiological events. Annexins (and changes in their cellular localization) have been associated with touch (Thonat et al. 1997) and gravity (Clark et al. 2000) responses, Nod signaling in Medicago (de Carvalho-Niebel et al. 2002), and diurnal cycles (Gachon et al. 2004). Furthermore there is a strong apparent involvement of annexins in abiotic stresses, primarily temperature, salt and osmotic stress (Gidrol et al. 1996, Kovacs et al. 1998, Breton et al. 2000, Cantero et al. 2006). Expression profiling of Arabidopsis' eight annexin genes using RT-PCR demonstrated that all eight genes are expressed in germinated seeds and that expression continues to increase over initial 7 days' growth (Cantero et al. 2006); only two genes are expressed in response to light-activation of etiolated seedlings, while most genes are expressed during salt, drought, and highand low-temperature conditions. Extensins are hydroxyproline-rich glycoproteins which are abundant in the cell walls of higher plants, and they have been

shown to be involved in enhancing stem thickness, with an indirect effect on stem height when the Arabidopsis Atext1 extensin coding sequence is under the transcriptional control of the strong constitutive CaMV 35S promoter (Roberts and Shisat 2006). A systems approach to the description of wall biosynthesis in plants was described by Farrokhi et al. (2006). Prohibitins play a role in cell-cycle progression, senescence, apoptosis, and maintenance of mitochondrial function in mammals and yeast. Using virus-induced gene silencing (VIGS) of two prohibitin subunit genes of Nicotiana benthamiana, designated NbPHB1 and NbPHB2 were targeted to the mitochondria, and their gene expression was suppressed during senescence resulting in growth inhibition, leaf yellowing and symptoms of cell death (Ahn et al. 2006). At the cellular level, depletion of these subunits affected mitochondria by substantially reducing their number and/or mass, and by causing morphological and physiological abnormalities. Suppression of prohibitin function resulted in a 10- to 20-fold higher production of ROS and induced premature leaf senescence while disruption of prohibitin function rendered the plants more susceptible to various oxidative stress-inducing reagents, including H2O2, paraquat, antimycin A and salicylic acid. Authors conclude that prohibitins play a crucial role in mitochondrial biogenesis and protection against stress and senescence in plant cells.

Ahn CS, Lee J-H, Hwang A-R, Kim W-T, Pai H-S (2006) Prohibitin is involved in mitochondrial biogenesis in plants. The Plant Journal 46, 658-667 Breton G, Vazquez-Tello A, Danyluk J, Sarhan F (2000) Two novel intrinsic annexins accumulate in wheat membranes in response to low temperature. Plant Cell Physiology 41, 177-184 Cantero A, Barthakur S, Bushart TJ, Chou S, Morgan RO, Fernandez MP, Clark GB, Roux SJ (2006) Expression profiling of the Arabidopsis annexin gene family during germination, de-etiolation and abiotic stress. Plant Physiology and Biochemistry 44, 13-24 Clark GB, Rafati DS, Bolton RJ, Dauwalder M, Roux SJ (2000) Redistribution of annexin in gravistimulated pea plumules. Plant Physiology and Biochemistry 38, 937-947 de Carvalho-Niebel F, Timmers ACJ, Chabaud M, Defaux-Petras A, Barker DG (2002) The Nod factor-elicited annexin MtAnn1 is preferentially localised at the nuclear periphery in symbiotically activated root tissues of Medicago truncatula. The Plant Journal 32, 343-352 Farrokhi N, Burton RA, Brownfield L, Hrmova M, Wilson SM, Bacic A, Fincher GB (2006) Plant cell wall biosynthesis: genetic, biochemical and functional genomics approaches to the identification of key genes. Plant Biotechnology Journal 4, 145-167 Gachon C, Mingam A, Charrier B (2004) Real-time P.C.R., what relevance to plant studies? Journal of Experimental Botany 55, 1445-1454 Gidrol X, Sabelli PA, Fern YS, Kush AK (1996) Annexin-like protein from Arabidopsis thaliana rescues delta oxyR mutant of Escherichia coli from H2O2 stress. Proceedings of the National Academy of Sciences USA 93, 11268-11273 Kovacs I, Ayaydin F, Oberschall A, Ipacs I, Bottka S, Dudits D, Toth EC (1998) Immunolocalization of a novel annexin-like protein encode by a stress and abscisic acid responsive gene in alfalfa. Plant Journal 15, 185-197 Roberts K, Shirsat AH (2006) Increased extensin levels in Arabidopsis affect inflorescence stem thickening and height. Journal of Experimental Botany 57, 537-545

Thonat C, Mathieu C, Crevecoeur M, Penel C, Gaspar T, Boyer N (1997) Effects of a mechanical stimulation on localization of annexin-like proteins in Bryonia dioica internodes. Plant Physiology 114, 981-988

Chromosomal, cellular and tissue events (leading to growth, development and differentiation) Telomestatin, an inhibitor of human telomerase activity, was bound in a dose-dependent manner to plant telomeric repeat sequence, and was found to inhibit telomerase activity in Arabidopsis thaliana and Oryza sativa suspension-cultured cells, suggesting the importance of telomerase in the survival of proliferating plant cells by maintaining telomere length, and that erosion of the telomere triggers cell death (Zhang et al. 2006). Seguí-Simarro and Staehelin (2006a), in addition to their upcoming review (Seguí-Simarro and Staehelin 2006b) of cytokinesis, also present a colourful display of the events underlying the cell cycle-dependent changes in cell architecture of shoot apical meristem cells of A. thaliana. In other studies aimed at further reinforcing the fact that development relies on the regulation of the cell cycle and the commitment of cells to differentiation, Siddiqui et al. (2006) reveal a critical role for AtCAP-C during cell division. CAP-C, like CAP-E, is a member of the structural maintenance of chromosomes (SMC) family of ATPases, form a heterodimer, the activity of which is controlled by the non-SMC subunits CAP-D2, CAP-G and CAP-H. Peptide transporters assist in the transport of peptides or peptide derivatives across membranes in an energy-dependent manner, and are classified as either being of the ATP-binding cassette transporters (ABC family), the peptide transporters (PTR family) or the oligopeptide transporters (OPT family). A. thaliana OPT (AtOPT) expression was studied in several organs, in which different AtOPTs were expressed (Stacey et al. 2006), highlighting their distinctive cellular roles, particularly nitrogen mobilization during germination and senescence, pollen tube growth, pollen and ovule development, seed formation and metal transport. Palanivelu and Preuss (2006) developed an in vitro assay to study pollen tube guidance to excised A. thaliana ovules. Using this assay they discerned the temporal and spatial regulation and species-specificity of late stage guidance signals and characterized the dynamics of pollen tube responses. Another marked plant developmental event was the discovery, through the use of RT-PCR, that arabinogalactan protein genes, possibly pollen-specific, are expressed during pollen tube development (Pereira et al. 2006). The pollen S-determinant gene, SP11, is sporophytically expressed in the anther tapetum of crucifers, and the pollen self-incompatibility phenotype is determined by the dominance relationships between the two S-haplotypes it carries. Shiba et al. (2006) discuss how tissue-specific monoallelic de novo DNA methylation is involved in determining the dominance interactions that determine the cruciferous self-incompatibility phenotype, while a broader discussion in the Brassicaceae is reviewed by Watanabe et al. (2006). Male recombination has been further elucidated by Wang and Yang (2006) who showed how the ARABIDOPSIS SKP1-LIKE1 (ASK1) protein, a member of a larger group of ubiquitin ligases that target a variety of proteins for degradation via the 26S proteasome pathway, is predominately expressed from leptotene to pachytene, and negatively regulates recombination. Nuclear Transport Factor 2 (NTF2) is a small

RanGDP-binding protein responsible for the nuclear import of Ran, a multifunctional small GTPase that is involved in nucleocytoplasmic transport, mitotic spindle assembly, and nuclear envelope formation. Two A. thaliana orthologs (AtNTF2a and AtNTF2b) were characterized by Zhao et al. (2006), who concluded that the nuclear import of Ran is functionally conserved in plants. Regulated intramembrane proteolysis (RIP) is a fundamental mechanism for controlling a wide range of cellular functions. Cleavage of membrane embedded proteins results in soluble fragments exerting their function, e.g., as transcription factors and thereby regulating gene expression. Bölter et al. (2006) describe a chloroplastic membrane protease which belongs to the conserved S2P family of membrane metallo proteases and show that it is localized in the inner envelope membrane and is essential for plant development. It could function in a RIP-like process regulating the concordant action in the plant cytosol, nucleus and plastids. Analysis of the cell using biosensors and bioreporters has been reviewed in the Journal of Experimental Botany 57(1). Cellular techniques for the future of plant science are also reviewed in several chapters of Volume IV of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. Using GFP reporter constructs, Lee et al. (2006) provide a systematic overview of regulation of transcription factor (TF) expression at a cellular level in Arabidopsis roots; knowledge of how TF genes express is essential for reconstructing gene regulatory networks. Overexpression of CYCLIN D3;1 (CYCD3;1) in transgenic A. thaliana plants increases mitotic cycles and reduces endocycles, and using cell suspension cultures, Menges et al. (2006) found that CYCD3;1 dominantly drives the G1/S transition. Csala et al. (2006) review the endoplasmic reticulum, which compartmentalizes biochemical reactions and processes of cell. Homologous recombination (HR) is typified by a heteroduplex DNA that is formed as a consequence of strand invasion and when the two homologous strands differ in sequence, a mismatch is generated. Emmanuel et al. (2006) analysed the roles of AtMSH2 ­ a gene coding for a mismatch repair protein ­ in suppression of recombination in Arabidopsis, demonstrating that AtMSH2 has a broad range of anti-recombination effects: it suppresses recombination between divergent direct repeats in somatic cells or between homologues from different ecotypes during meiosis. The Arabidopsis transcription factors AINTEGUMENTA and JAGGED promote organ growth by maintaining cellular proliferation potential and thus indirectly determine the fate of organ size. Loss of the Antirrhinum transcription factor CINCINNATA causes leaf overgrowth, yet also leads to a highly abnormal leaf shape. Disch et al. (2006) found, for the first time ever, a novel RING-finger protein BIG BROTHER (BB) which is a repressor of plant organ growth and size. Cells divide during cytokinesis by building a new cell wall within the cytoplasm in a few minutes, and the primordial structure, the cell plate, is made up of cell surface material, including plasma membrane proteins, cell wall components, and exogenously applied endocytic tracers even if de novo protein synthesis is blocked. In addition to these findings, Dhonukshe et al. (2006) noted that cytokinesis-specific syntaxin KNOLLE as

well as plasma membrane (PM) resident proteins localize to endosomes that fuse to initiate the cell plate. A single wak2 mutation in Arabidopsis was shown to exhibit a dependence on sugars and salts for seedling growth (Kohorn et al. 2006). WAKs or wall-associated kinases are a family of five proteins that contain extracellular domains that can be linked to pectin molecules of the cell wall, span the plasma membrane and have a cytoplasmic serine/threonine kinase domain. According to Mathur (2006) it is not so much the turgor pressure itself that leads to localized cell growth and expansion, but rather the capacity to identify weak regions in the cell boundary and thus creating discrete intracellular domains for targeting the growth machinery. According to him, plant cells take shape as a result of a co-ordination of these main factors: Membrane-interacting phospholipases, Rho-like proteins and their interactors, an actin-modulating ARP2/3 complex with its upstream regulators, and actin­microtubule interactions. DNA double-strand breaks or DSBs arise from exposure to DNA damaging agents and also from cell metabolism. Bleuyard et al. (2006) provide an update on recent advances in understanding of the DSB repair machinery of plants, focusing on Arabidopsis. PARTING DANCERS is a novel gene required for normal crossing-over events during meiotic homologous recombination (Wijeratne et al. 2006). Kurdyukov et al. (2006) noted that in the A. thaliana mutant bodyguard (bdg) defects characteristic of the loss of cuticle structure were observed, but these did not result from a lack of typical cutin monomers, but rather due to the accumulation of more cell wall-bound lipids and epicuticular waxes. One of the authors' proposals is that BDG codes for an extracellular synthase responsible for the formation of cuticle.

Bleuyard J-Y, Gallego ME, White CI (2006) Recent advances in understanding of the DNA double-strand break repair machinery of plants. DNA Repair 5, 1-12 Bölter B, Nada A, Fulgosi H, Soll J (2006) A chloroplastic inner envelope membrane protease is essential for plant development. FEBS Letters 580, 789-794 Csala M, Bánhegyi G, Benedetti A (2006) Endoplasmic reticulum: A metabolic compartment. FEBS Letters 580, 2160-2165 Disch S, Anastasiou E, Sharma VK, Laux T, Fletcher JC, Lenhard M (2006) The E3 ubiquitin ligase BIG BROTHER controls Arabidopsis organ size in a dosage-dependent manner. Current Biology 16, 272-279 Dhonukshe P, Baluska F, Schlicht M, Hlavacka A, Samaj J, Friml J, Gadella TWJ (2006) Endocytosis of cell surface material mediates cell plate formation during plant cytokinesis. Developmental Cell 10, 137-150 Emmanuel E, Yehuda E, Melamed-Bessudo C, Avivi-Ragolsky N, Levy A A (2006) The role of AtMSH2 in homologous recombination in Arabidopsis thaliana. EMBO Reports 7, 100-105 Kohorn BD, Kobayashi M, Johansen S, Riese J, Huang L-F, Koch K, Fu S, Dotson A, Byers N (2006) An Arabidopsis cell wall-associated kinase required for invertase activity and cell growth. The Plant Journal 46, 307-316 Kurdyukov S, Faust A, Nawrath C, Bär S, Voisin D, Efremova N, Franke R, Schreiber L, Saedler H, Métraux JP, Yephremov A (2006) The epidermis-specific extracellular BODYGUARD controls cuticle development and morphogenesis in Arabidopsis. The Plant Cell 18, 321-339 Lee J-Y, Colinas J, Wang J-Y, Mace D, Ohler U, Benfey PN (2006) Transcriptional and posttranscriptional regulation of transcription factor expression in Arabidopsis roots. Proceedings of the National Academy of Sciences USA 103, 6055-6060 Mathur J (2006) Local interactions shape plant cells. Current Opinion in Cell Biology 18, 40-46 Menges M, Samland AK, Planchais S, Murray JAH (2006) The D-type cyclin CYCD3;1 is limiting for the G1-to-S-phase transition in Arabidopsis. The Plant Cell 18, 893-906 Palanivelu R, Preuss D (2006) Distinct short-range ovule signals attract or repel Arabidopsis thaliana pollen tubes in vitro. BMC Plant Biology 6, 7 Pereira LG, Coimbra S, Oliveira H, Monteiro L, Sottomayor M (2006) Expression of arabinogalactan protein genes in pollen tubes of Arabidopsis thaliana. Planta 223, 374-380 Seguí-Simarro JM, Staehelin LA (2006a) Cell cycle-dependent changes in

Golgi stacks, vacuoles, clathrin-coated vesicles and multivesicular bodies in meristematic cells of Arabidopsis thaliana: A quantitative and spatial analysis. Planta 223, 223-236 Seguí-Simarro JM, Staehelin LA (2006b) Mechanisms of cytokinesis in flowering plants: new pieces for an old puzzle. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 185-196 Shiba H, Kakizaki T, Iwano M, Tarutani Y, Watanabe M, Isogai A, Takayama S (2006) Dominance relationships between self-incompatibility alleles controlled by DNA methylation. Nature Genetics 38, 297-299 Siddiqui NU, Rusyniak S, Hasenkampf CA, Riggs CD (2006) Disruption of the Arabidopsis SMC4 gene, AtCAP-C, compromises gametogenesis and embryogenesis. Planta 223, 990-997 Stacey MG, Osawa H, Patel A, Gassmann W, Stacey G (2006) Expression analyses of Arabidopsis oligopeptide transporters during seed germination, vegetative growth and reproduction. Planta 223, 291-305 Wang Y, Yang M (2006) The ARABIDOPSIS SKP1-LIKE1 (ASK1) protein acts predominately from leptotene to pachytene and represses homologous recombination in male meiosis. Planta 223, 613-617 M Watanabe, G Suzuki, H Shiba, S Takayama (2006) Molecular mechanisms of self-incompatibility in Brassicaceae. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 552-555 Wijeratne AJ, Chen C, Zhang W, Timofejeva L, Ma H (2006) The Arabidopsis thaliana PARTING DANCERS gene encoding a novel protein is required for normal meiotic homologous recombination. Molecular Biology of the Cell 17, 1331-1343 Zhang L, Tamura K, Shinya K, Takahashi H (2006) The telomerase inhibitor telomestatin induces telomere shortening and cell death in Arabidopsis. Biochimica et Biophysica Acta - Molecular Cell Research 1763, 39-44 Zhao Q, Leung S, Corbett AH, Meier I (2006) Identification and characterization of the Arabidopsis orthologs of Nuclear Transport Factor 2, the nuclear import factor of Ran. Plant Physiology 140, 869-878

Cold and freezing tolerance Chorispora bungeana (Brassicaceae), an alpine subnival plant and perennial herb growing in the freeze-thaw tundra on the border of glaciers where almost all other flowering plants have great difficulty in growing, can survive frequent temperature fluctuations and freezing temperatures. A novel MAPK, CbMAPK3, closely related to Arabidopsis AtMPK3, was isolated from Chinese-originated C. bungeana and characterized (Zhang et al. 2006). MAPKs, or mitogen-activated protein kinases form part of phosphorylation cascades (signal transduction systems) that mediate the activation/deactivation of genes in response to stimuli. Transgenic Nicotiana tabacum and N. alata plants harbouring a new cold-inducible genetic construct consisting of a chloroplast-specific omega-3-fatty acid desaturase gene (FAD7) under the control of a cold-inducible promoter (cor15a) from A. thaliana showed marked increases in survival rates when placed in cold storage (0-4°C) over prolonged periods of time (44-50 days) (Khodakovskaya et al. 2006). A review by Moffatt et al. (2006) describes the importance of antifreeze proteins in plant protection and as modulators of freezing and ice recrystallization. Molecular mechanisms are discussed. In fact almost all of the entire contents of this issue of Physiologia Plantarum is dedicated to cold stress and cold/freezing tolerance mechanisms, and readers are further advised to consult the issue for more details and updates. Of worthy mention is the use of phosphoproteomics to unravel plant regulatory mechanisms, which is underlined by phosphorylation of proteins (de la Fuente van Bentem et al. 2006). Allan et al. (2006) showed that a short heat pre-treatment (1 h at 38°C) was found to protect both suspension-cultured apple fruit cells and tobacco cells ­ with a large burst of H2O2 from the latter ­ from cold-induced cell death. Alpine plants offer unique models to study nitrogen and carbon reserve metabolism (Monson et al. 2006).

Several cold acclimation-responsive Rhododendron genes for lipid metabolism, membrane transport and lignin biosynthesis were identified from low/moderately abundant ESTs (Wei et al. 2006). Molecular strategies for modifying lipid content have been revised by Murphy (2006). The death of chilling-sensitive plants was attributed to an insufficient unsaturation of fatty acids. In order to overcome this deficit Kholodova et al. (2006) developed transgenic tobacco lines that had the acyl-lipid -9 desaturase gene from Synechococcus vulcanus, resulting in lines with increased chilling tolerance. Transgenic strategies for cold-stress induction has been well-covered in Volume III of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. Verslues et al. (2006) present several protocols useful for the measurement of biotic and abiotic stresses: the use of polyethylene glycol-infused agar plates to impose low water potential stress, assay of salt tolerance based on root elongation, quantification of freezing tolerance and the use of electrolyte leakage experiments to quantify cellular damage induced by freezing and low water potential.

Allan AC, Maddumage R, Simons JL, Neill SO, Ferguson IB (2006) Heat-induced oxidative activity protects suspension-cultured plant cells from low temperature damage. Functional Plant Biology 33, 67-76 de la Fuente van Bentem S, Roitinger E, Anrather D, Csaszar E, Hirt H (2006) Phosphoproteomics as a tool to unravel plant regulatory mechanisms. Physiologia Plantarum 126, 110-119 Khodakovskaya M, McAvoy R, Peters J, Wu H, Li Y (2006) Enhanced cold tolerance in transgenic tobacco expressing a chloroplast -3 fatty acid desaturase gene under the control of a cold-inducible promoter. Planta 223, 1090-1100 Kholodova VP, Meshcheryakov AB, Rakitin VY, Karyagin VV, Kuznetsov VV (2006) Hydraulic signal as a "primary messenger of water deficit" under salt stress in plants. Doklady Biological Sciences 407, 155-157 Moffatt B, Ewart V, Eastman A (2006) Cold comfort: plant antifreeze proteins. Physiologia Plantarum 126, 5-16 Monson RK, Rosenstiel TN, Forbis TA, Lipson DA, Jaeger CH III (2006) Nitrogen and carbon storage in alpine plants. Integrative and Comparative Biology 46, 35-48 Murphy DJ (2006) Molecular breeding strategies for the modification of lipid composition. In Vitro Cellular and Developmental Biology - Plant 42, 88-99 Verslues PE, Agarwal M, Katiyar-Agarwal S, Zhu J, Zhu J-K (2006) Methods and concepts in quantifying resistance to drought, salt and freezing, abiotic stresses that affect plant water status. The Plant Journal 45, 523-539 Wei H, Dhanaraj AL, Arora R, Rowland LJ, Fu Y, Sun L (2006) Identification of cold acclimation-responsive Rhododendron genes for lipid metabolism, membrane transport and lignin biosynthesis: importance of moderately abundant ESTs in genomic studies. Plant, Cell and Environment 29, 558-570 Zhang T, Liu Y, Xue L, Xu S, Chen T, Yang T, Zhang L, An L (2006) Molecular cloning and characterization of a novel MAP kinase gene in Chorispora bungeana. Plant Physiology and Biochemistry 44, 78-84

chromosome number stability, alteration in VNTR (variable number tandemly repeats) sequences and hypericin content, in plants after pre-culture, and two subsequent cryogenic steps (cryoprotection and cooling) and those recovered from cryopreserved meristems. The following non-Hypericum specific primers were used (derived from human and rice minisatellite sequences): (HVR- 5- CCCTCCTCCTCCTTC-3, HVR+ 5-AGGAGGAGGGGAAGG-3, YNZ22 5-CTCTGGG-TGTGGTGC-3, FVIIexB-C 5-TACGTGTGTGTGTCC-3, FVIIex8 5-ATCGCACACACACAGG-3, HBV35-GGTGAAGCACAGGTG-3, HBV5 5-GGTGTAGA GAGGGGT-3, OGRB01 5- AGGGCTGGAGGAGGGC-3). The shoot tips of three Rosa cvs. showed regrowth percentages of 64.44, 67.73 and 57.57% for Kardinal, Fairy and Maidy, respectively, after cryopreservation by Halmagyi and Pinker (2006) as follows: dehydration with concentrated PVS2 cryoprotective solution for 10-30 min at room temperature, prior to a direct plunge in liquid nitrogen. Interestingly, prior to dehydration shoot tips (1-4 mm long) were incubated in a liquid MS medium supplemented with 2.5 mg/l thiamine, 0.2 mg/l biotin, 0.2 mg/l pyridoxine, 0.25 mg/l BAP, 0.5 mg/l GA3 and 0.08 M sucrose for 24 h. Hyperhydricity was not reported. Although not specifically tested in cryopreservation, hyaluronic acid (HA) hydrogel beads were prepared by photopolymerization of methacrylated HA and N-vinylpyrrolidone using alginate as a temporal spherical mold (Bae et al. 2006). The system was tested on bovine cells, but may present a new alternative to the conventionally-used calcium alginate beads used in plant science. Fukai et al. (2006) showed, following the cryopreservation of pollen of the sex-changing plant, Arisaema sikokianum, an attractive ornamental, that this species is self-compatible. Parameters were optimized for somatic embryogenesis and cryopreservation of Pinus roxburghii embryogenic cultures using shoot apical domes from mature trees (Malabadi and Nataraja 2006).

Bae KH, Yoon J-J, Park T-G (2006) Fabrication of hyaluronic acid hydrogel beads for cell encapsulation. Biotechnology Progress 22, 297-302 Fukai S, Hasegawa A, Kobayashi T (2006) The sex changing plant Arisaema sikokianum Franch. et Siva (Araceae) is self-compatible. Propagation of Ornamental Plants 6, 39-43 Halmagyi A, Pinker I (2006) Plant regeneration from Rosa shoot tips cryopreserved by a combined droplet vitrification method. Plant Cell, Tissue and Organ Culture 84, 129-137 Malabadi RB, Nataraja K (2006) Cryopreservation and plant regeneration via somatic embryogenesis using shoot apical domes of mature Pinus roxburghii Sarg. trees. In Vitro Cellular and Developmental Biology Plant 42, 152-159 Urbanová M, Kosuth J, Cellárová E (2006) Genetic and biochemical analysis of Hypericum perforatum L. plants regenerated after cryopreservation. Plant Cell Reports 25, 140-147 Volk GM, Walters C (2006) Plant vitrification solution 2 lowers water content and alters freezing behavior in shoot tips during cryoprotection. Cryobiology 52, 48-61

Cryopreservation Cryoprotectant solutions are used to dehydrate cells and decrease lethal ice formation when preserving plant tissues in liquid nitrogen, typically at temperatures reaching -196°C. One such cryoprotectant, plant vitrification solution 2 or PVS2, is commonly used in cryopreservation. Volk and Walters used differential scanning calorimetry to examined the effect of PVS2 on the water content and phase behavior of mint and garlic shoot tips. Hypericum perforatum L. shoot-tips could be successfully cryopreserved over two generations (Urbanová et al. 2006). Hypericum is an important medicinal and ornamental plant, and several reviews may be found in Volume IV of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. Variation was evaluated by measuring survival rate,

Flower colour It is the uneven distribution of pigments that is responsible for the great variation in colour patterns observed in ornamental plant flowers, whose pigmentation, distribution and patterning is probably under strong regulatory and fine-tuned mechanisms. The diversity of color patterns in various species and cultivars indicates a diversity of these regulatory mechanisms. Marginal picotee is a flower colour pattern in which proximal and distal parts of the petals show different colors and

the whole flower shows a central spot of one color, encircled by a ring of another. This trait appears to be consistent among the angiosperms. Previously transposons were shown to be responsible for sectorial picotee, a pattern composed of differently colored sectors, in Japanese morning glory, Ipomoea nil and Dianthus caryophyllus, two ornamentals (Inagi et al. 1994, Iida et al. 1999, Hoshino et al. 2001, Itoh et al. 2002). Morita et al. (2006) used I. nil to study one group of transcriptional regulators for anthocyanin biosynthesis, members of proteins containing an R2R3-MYB domain, a bHLH (basic helix­loop­helix) domain and conserved WD40 repeats (WDRs). Spacial and temporal expression of the structural genes encoding the enzymes for anthocyanin biosynthesis is thought to be determined by combinations of the R2R3-MYB, bHLH and WDR factors and their interactions. While the wild-type I. nil exhibits blue flowers with colored stems and dark-brown seeds, the c mutants display white flowers with red stems and colored seeds, and the ca mutants exhibit white flowers with green stems and ivory seeds. Studies on the MYB genes are focused. Many Petunia cultivars demonstrate marginal picotee, and in `Baccara Rose Picotee' (with a white-margin and coloured-center) cinnamic acid derivatives and reduced transcript levels of CHS, which encodes an enzyme that catalyzes the conversion of cinnamic acids into flavonoids, were observed specifically in the margin of the corolla throughout all stages of flower development (Saito et al. 2006). Pattern formation in Petunia has also incidentally been achieved through transgenic approaches by over-expressing CHS, F3H or DFR (35S promoter-controlled) occasionally induced repression of anthocyanin biosynthesis by post-transcriptional gene silencing, resulting in pattern formation (Napoli et al. 1990, van der Krol et al. 1990, van Blokland et al. 1994). White corolla sector in Petunia `Red Star' was attributed to the induction of post-transcriptional gene silencing by dsRNA derived from the 3UTR of CHS transcripts (Metzlaff et al. 1997, Koseki et al. 2005). Yoshioka et al. (2006) describe a method that allows for the quantification of petal shape and picotee colour pattern based on PC-based methods and image analyses, and even though their study was tested on lisianthus (Eustoma grandiflorum), the applicability to other ornamentals is large. In hydrangea plants, the sepals, which are often much more conspicuous than petals, result in the decorative colouration. These sepals are composed of decorative (large and colored) and nondecorative (small and inconspicuous) flowers (Uemachi et al. 2004). Green-flowering hydrangea are at present very popular, but propagation through cuttings may result in unstable colouration (green, blue-green or even blue flowers). One of the factors that may affect the stability of this green colouraton may be related to the presence of a type of virus or bacterium infecting the plant. In Japan, hydrangea plants infected with the Japanese hydrangea phyllody (JHP) phytoplasma produce green flowers; phytoplasmas, cell-wall-less plant pathogenic bacteria, when infecting herbaceous plants, lead to virescence (= development of green flowers and the loss of normal flower pigments) and phyllody (the development of floral parts into leafy structures) (McCoy et al. 1989, Kirpatrick 1992, Agrios 1997). Universal 16S rRNA PCR primers have been designed to detect phytoplasmas (Lee et al. 2000). Kesumawati et al. (2006) showed that green-colouration stability is related to the

concentration of the phytoplasma, and concluded that the JHP-phytoplasma concentration in green sepals was 16 times higher than that in blue-green sepals. Wellmann et al. (2006) challenge the classical theory that anthocyanidins derive from (+)-naringenin via (2R,3R)-dihydroflavonol(s) and (2R,3S,4S)-leucocyanidin(s) which are eventually oxidized by anthocyanidin synthase (ANS). They also question the role of ANS because the recombinant enzyme from Arabidopsis exhibited primarily flavonol synthase (FLS) activity with negligible ANS activity, leading to the proposal that ANS as well as FLS may select for dihydroflavonoid substrates carrying a "-face" C-3 hydroxyl group and initially form the 3-geminal diol by "-face" hydroxylation. Their claims were substantiated by assays with recombinant ANS from Gerbera hybrida and were extended to catechin and epicatechin isomers as potential substrates to delineate the enzyme specificity. Hieber et al. (2006) characterized the yellow and red colouration in commercially important bi-color Oncidium Gower Ramsey by chromatography, revealing that the predominant yellow pigment was an equal mixture of all-trans and 9-cis isomers of violaxanthin, with esterification specific to the 9-cis isomer and that red markings were comprised of the anthocyanins cyanidin and its methylated derivate, peonidin. Furthermore, expression profiling of five key pigment biosynthesis genes encoding dihydroflavonol 4-reductase, phytoene synthase, phytoene desaturase, carotenoid isomerase, and the downstream 9-cis epoxycarotenoid dioxygenase were determined. Variations caused by insertion events characterized a number of the isolated anthocyanin and carotenoid genes. Mori et al. (2006) provide a detailed phytochemical description of blue coloration in Phacelia campanularia, an attractive wild-flower commonly known as California Bluebell. Flavonoid 3-hydroxylase (GtF3H) and flavone synthase II (GtFSII) homologues were isolated from gentian (Gentiana triflora) petals and transformed into tobacco plants; GtF3 H transformants resulted in a slight increase in anthocyanin content and flower color intensity, and conversion of the flavonol quercetin from kaempferol while GtFSII transformants showed a remarkable reduction in anthocyanin content and flower color intensity, and additional accumulation of flavone, especially luteolin derivatives (Nakatsuka et al. 2006a). Another study by Nakatsuka et al. (2006b) on Gentiana scabra, pink-flowered plants were bred from spontaneous mutations of blue-flowered plants. The loss of delphinidin synthesis was attributed to the insertions of different transposable elements (classified into an hAT superfamily and terminal-repeat retrotransposon in miniature (TRIM)) in the F3,5H gene in each independent pink-flowered gentian plant. Schwinn et al. (2006) showed, through mutant phenotype analyses, that the Rosea1, Rosea2, and Venosa genes, which encode MYB-related transcription factors active in the flowers of Antirrhinum majus, control the intensity and pattern of magenta anthocyanin pigmentation in flowers. Readers are referred to several chapters within Volume I of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues for general concepts and considerations of flower colour formation and patterning, primarily in A. thaliana and A. majus.

Hieber AD, Mudalige-Jayawickrama RG, Kuehnle AR (2006) Color genes

in the orchid Oncidium Gower Ramsey: identification, expression, and potential genetic instability in an interspecific cross. Planta 223, 521-531 Hoshino A, Johzuka-Hisatomi Y, Iida S (2001) Gene duplication and mobile genetic elements in the morning glories, Gene 7, 1-10 Iida S, Hoshino A, Johzuka-Hisatomi Y, Habu Y, Inagaki Y (1999) Floricultural traits and transposable elements in the Japanese and common morning glories. Annals of the New York Academy of Science 18, 265-274 Inagaki Y, Hisatomi Y, Suzuki T, Kasahara K, Iida S (1994) Isolation of a suppressor-mutator/enhancer-like transposable element, Tpn1, from Japanese morning glory bearing variegated flowers. Plant Cell 6, 375-383 Itoh Y, Higeta D, Suzuki A, Yoshida H, Ozeki Y (2002) Excision of transposable elements from the chalcone isomerase and dihydroflavonol 4-reductase genes may contribute to the variegation of the yellow-flowered carnation (Dianthus caryophyllus). Plant Cell Physiology 43, 578-585 Kesumawati E, Kimata T, Uemachi T, Hosokawa M, Yazawa S (2006) Correlation of phytoplasma concentration in Hydrangea macrophylla with green-flowering stability. Scientia Horticulturae 108, 74-78 Koseki M, Goto K, Masuta C, Kanazawa A (2005) The star-type color pattern in Petunia hybrida `Red Star' flowers is induced by the sequence-specific degradation of the chalcone synthase RNA. Plant Cell Physiology 46, 1879-1883 Metzlaff M, O'Dell M, Cluster PD, Flavell RB (1997) RNA-mediated RNA degradation and chalcone synthase A silencing in petunia. Cell 21, 845-854 Mori M, Kondo T, Toki K, Yoshida K (2006) Structure of anthocyanin from the blue petals of Phacelia campanularia and its blue flower color development. Phytochemistry 67, 622-629 Morita Y, Saitoh M, Hoshino A, Nitasaka E, Iida S (2006) Isolation of cDNAs for R2R3-MYB, bHLH and WDR transcriptional regulators and identification of c and ca mutations conferring white flowers in the Japanese Morning Glory. Plant and Cell Physiology 47, 457-470 Nakatsuka T, Nishihara M, Mishiba K, Yamamura S (2006a) Heterologous expression of two gentian cytochrome P450 genes can modulate the intensity of flower pigmentation in transgenic tobacco plants. Molecular Breeding 17, 91-99 Nakatsuka T, Nishihara M, Mishiba K, Hirano H, Yamamura S (2006b) Two different transposable elements inserted in flavonoid 3,5-hydroxylase gene contribute to pink flower coloration in Gentiana scabra. Molecular Genetics and Genomics 275, 231-241 Napoli C, Lemieux C, Jorgensen R (1990) Introduction of a chimeric chalcone synthase gene into Petunia results in reversible co-suppression of homologous genes in trans. Plant Cell 2, 279-289 Saito R, Fukuta N, Ohmiya A, Itoh Y, Ozeki Y, Kuchitsu K, Nakayama M (2006) Regulation of anthocyanin biosynthesis involved in the formation of marginal picotee petals in Petunia. Plant Science 170, 828-834 Schwinn K, Venail J, Shang Y, Mackay S, Alm V, Butelli E, Oyama R, Bailey P, Davies K, Martin C (2006) A small family of MYB-regulatory genes controls floral pigmentation intensity and patterning in the genus Antirrhinum. The Plant Cell 18, 831-851 van Blokland R, van der Geest N, Mol JNM, Kooter JM (1994) Transgene-mediated s suppression of chalcone synthase expression in Petunia hybrida results from an increase in RNA turnover. Plant Journal 6, 861-877 van der Krol AR, Mur LA, Beld M, Mol JN, Stuitje AR (1990) Flavonoid genes in petunia: addition of a limited number of gene copies may lead to a suppression of gene expression. Plant Cell 2, 291-299 Wellmann F, Griesser M, Schwab W, Martens S, Eisenreich W, Matern U, Lukacin R (2006) Anthocyanidin synthase from Gerbera hybrida catalyzes the conversion of (+)-catechin to cyanidin and a novel procyanidin. FEBS Letters 580, 1642-1648 Yoshioka Y, Ohsawa R, Iwata H, Ninomiya S, Fukuta N (2006) Quantitative evaluation of petal shape and picotee color pattern in lisianthus by image analysis. Journal of the American Society for Horticultural Science 131, 261-266

Flower evocation/development/formation Flower morphology in higher plants is established by the concerted action of a series of MADS-box transcription factors. These result in a spatial and temporal regulation of flower organ development. Genetic and molecular analyses of flower-specific MADS-box genes and floral homeotic mutants enabled an understanding of their role and led to the proposal of the classic ABC model, pioneered by Coen and Meyerowitz (1991) and established from Arabidopsis and Antirrhinum majus model plants (reviewed in Volume I of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues). In their model flower organs are arranged in four homocentric whorls on the flower. Sepals originate in the outermost whorl 1 from the action of A-class MADS-box genes alone; petals in whorl 2 from the combined action of A-class and B-class MADS-box

genes; anthers in whorl 3 from the combined action of B-class and C-class MADS-box genes; and finally carpels in the inner whorl 4 from the action of C-class MADS-box genes alone. Theißen et al. (2000) then revealed that the relationship was not so linear, and that exceptions occurred. A modified version of the classical ABC model is used to describe flower morphology in many monocotyledonous plants (Kanno 2006). In addition to functions A, B and C, D-class MADS-box gene(s) result in ovule development (originating from findings in petunia; Angenent and Colombo 1996) or A. thaliana (SEEDSTICK; Pinyopich et al. 2003) while the E-class is required for B and C floral organ identity functions (Theißen 2000, Pelaz et al. 2000, Honma and Goto 2001); quartets of MADS-box genes were thus thought to be involved in flower organ formation (Honma and Goto 2001, Theißen et al. 2002, Jack 2004). RT-PCR analyses of a class B gene MaDEF isolated from Muscari armeniacum (Asparagales) revealed that this gene is expressed in outer tepals as well as in inner tepals and stamens (Nakada et al. 2006), a pattern similarly shared by tulip. Of particular interest was the use of laser microdissection (LMD) to isolate floral organ-specific RNA. APETALA1 (AP1) is a floral homeotic gene that specifies floral meristem identity and sepal and petal identity in Arabidopsis. Sundström et al. (2006) using chromatin immunoprecipitation, we show that the floral homeotic PISTILLATA (PI) protein, required for petal and stamen development, together with APETALA3 (AP3), has the ability to bind directly to the promoter region of AP1, restricting the expression of AP1 during early stages of floral development. AP2 functions in stem cell maintenance by modifying the WUS-CLV3 feedback loop (Würschum et al. 2006). BAM1 (derived from barely any meristem 1), BAM2 and BAM3 receptor-like kinases are important players in maintaining meristem function in Arabidopsis, similar to their closely-related CLV1 receptor-kinase (DeYoung et al. 2006). The shoot apical meristem (SAM) is a small group of undifferentiated dividing cells which is responsible for the continuous growth of plants. WUSCHEL (WUS) from A. thaliana is required for maintenance of a stem cell pool in the SAM while several genes have been identified that control the development and maintenance of the SAM, including the MADS-box gene AGAMOUS, which, in combination with an unknown factor, has been proposed as a possible negative regulator of WUS, leading to the termination of meristematic activity within the floral meristem. Ferrario et al. (2006) conducted molecular tests on transgenic P. hybrida in which the E-type and D-type MADS-box genes FLORAL BINDING PROTEIN2 (FBP2) and FBP11, respectively, were simultaneously overexpressed. They proposed a model that claims that a transcription factor complex consisting of C-, D-, and E-type MADS-box proteins controls the stem cell population in the floral meristem based on the following findings: a) an early arrest in the development of transgenic petunia plants at the cotyledon stage involved a possible combined action of FBP2 and FBP11 in repressing the petunia WUS homolog, TERMINATOR; b) the ectopic up-regulation of the C-type and D-type homeotic genes FBP6 and FBP7 (FBP = FLORAL BINDING PROTEIN), respectively, suggests that they may also participate in a complex, which causes the determinacy in transgenic plants.

RABBIT EARS (RBE) is a gene that regulates petal development in A. thaliana. Second-whorl petals in rbe mutants could be replaced with staminoid organs, stamens or filaments and some rbe flowers had increased numbers of sepals and exhibit fusion of sepals (Krizek et al. 2006). Zygomorphic flowers have bilateral or dorsoventral symmetry, and are considered to have evolved several times independently in flowering plants. In A. majus, floral dorsoventral symmetry depends on the activity of two TCP-box genes, CYCLOIDEA (CYC) and DICHOTOMA (DICH) whose function is mediated through an interaction with some specific MYB genes. When both CYC and DICH are mutated, more petals and stamens are developed in the dorsal region, and all petals resemble the shape of ventral petal. Feng et al. (2006) explored a model legume, Lotus japonicus to investigate the molecular mechanisms underlying the development of different zygomorphic flowers among angiosperms, and to examine whether the CYC homologues (especially LjCYC2) also play a role in the control of floral asymmetry in this papilionoid legume. They also found a lateralizing factor, Keeled wings in Lotus 1 (Kew1), which plays a key role in the control of lateral petal identity, and found that LjCYC2 interacts with Kew1, resulting in a double mutant that bears all petals with ventralized identity to a certain extent. Other results in L. japonicus by Guo et al. (2006) show how a CEN/TFL1-like gene, Ljcen1, which shares a 67-76% identity to its homologs from a variety of plant species, may be involved in phase transition of shoot apical meristem. CEN/TFL1 or CENTRORADIALIS/TERMINAL FLOWER 1 genes play an important role in the phase transition of plant flowering. Kwiatkowska (2006) used a non-invasive replica method and a 3-D reconstruction algorithm to study geometry changes, especially surface expansion, accompanying flower primordium formation at the reproductive shoot apex of Arabidopsis. Alpinia (Zingiberaceae) is characterized by flexistyly, i.e. styles that move during flowering, and in order to better understand the molecular mechanisms controlling floral development in this genus, B- and C-function genes were investigated, leading to the discovery of two PI- (PISTILLATA) and AG-(AGAMOUS)-like MADS-box genes that may be involved in petal, stamen, carpel, and ovule development in A. oblongifolia (Gao et al. 2006). Shogo Matsumoto and colleagues previously isolated the rose PI, AP3, AG and SEP homologues, MASAKO BP, MASAKO B3, MASAKO C1 and D1, and MASAKO S1 and S3, respectively, from Rosa rugosa (Kitahara and Matsumoto 2000, Kitahara et al. 2001 2004), as well as another class B MADS-box gene, MASAKO euB3, homologous to AP3 with an euAP3 lineage (Matsumoto and Kitahara 2005). In recent findings, transgenic Arabidopsis lines containing these genes: MASAKO BP and MASAKO B3 resulted in sepals-to-petals transformation while MASAKO BP gave carpel-to-stamen-like transformation while MASAKO euB3 lines showed a transformation from sepals to petals (Hibino et al. 2006). The homeotic transformation of sepals*1 to petals in tulip (Kanno et al. 2003), crocus (Tsaftaris et al. 2004 2005 2006) and other liliaceous plants (Kramer and Irish 2000, Kanno 2006)

*1

further strengthens the fact that a different mechanism is in play in monocots. Gene expression studies of Phalaenopsis equestris, a native diploid species of Phalaenopsis in Taiwan, orchid reproductive organs were performed when a cDNA library of mature flower buds was constructed, and a total of 5,593 expressed sequence tags (ESTs) from randomly selected clones were identified and characterized (Tsai et al. 2006), and may be useful in revealing the secrets behind the immense diversity in floral form within the Orchidaceae. An Arabidopsis/Antirrhinum LEAFY (LFY)/FLORICAULA (FLO) homolog was isolated from tropical cedar (Cedrela fissilis), CfLFY (Dornelas and Rodriguez). In addition to extensive genomic analyses of gene structure and function, the authors also transformed Arabidopsis lfy26 mutant lines with the CfLFY coding region, under the control of the LFY promoter, and showed that the wild-type phenotype could be restored, hinting thus that CfLFY is a FLO/LFY homolog probably involved in the control of tropical cedar reproductive development. Aloni et al. (2006) demonstrated the developmental pattern of auxin production during Arabidopsis floral-bud development, and suggested that young organs which produce high concentrations of free IAA inhibit or retard organ-primordium initiation and development at the shoot tip. Bennett et al. (2006) go further by introducing the reader to a MAX-dependent hormone, a novel regulator of auxin transport. In their theory, an as yet undefined hormone, whose synthesis in Arabidopsis requires MAX1, MAX3, and MAX4, moves up the plant and also inhibits shoot branching while auxin, moving down the plant in the main stem, indirectly inhibits axillary bud outgrowth. cDNAs possibly responsible for heteromorphy in Primula vulgaris were divided into 11 classes that were differentially expressed between developing floral morphs (McCubbin et al. 2006). A number of these classes were also shown to have significant homology to members of gene families implicated in plant development, including rapid alkalinization factors, DExH box RNA helicases, SKS multi-copper oxidases, and AtCHX ion-transporter families, consistent with their potential involvement in the regulation of floral heteromorphy; heteromorphic self-incompatibility systems provide an excellent model for studying both intraspecific breeding barriers and the regulation of floral organ size and positioning. Controlling flowering time in higher plants is one of the most important physiological processes and is critical for their reproductive success. Recent findings regarding cross-talk between floral promotion pathways and flowering locus T and suppressor of overexpression of Constans 1, the major floral integrators within Arabidopsis have been reviewed by Lee et al. (2006). Related to this is a review by Noh and Noh (2006) which highlights the importance of chromatin modifiers in the transcriptional activation and repression of the major floral repressor FLOWERING LOCUS C (FLC). A new mutant, designated delayed flowering (dfr) in the Landsberg erecta (Ler) ecotype, was identified with delayed flowering time under the different growth conditions, including long- and short-day photoperiods and gibberellic acid GA3 treatments, suggesting

From http://en.wikipedia.org: "A sepal is a tepal (a segment) of the calyx of a flower. The calyx is the outer part of the perianth, which comprises the sterile inner and outer tepals that are usually differentiated into petals and sepals. The term tepal is usually applied when the petals and sepals are not differentiated. However, in a "typical" flower the sepals are green and lie under the more conspicuous petals. When the flower is in bud, the sepals enclose and protect the more delicate floral parts within. The number of sepals in a flower (called merosity) is indicative of the plant's classification: eudicots having typically four or five sepals and monocots and palaeodicots having three, or some multiple of three, sepals."

that DFR is a gene involved in the autonomous flowering promotion pathway (Chen et al. 2006). In addition, FLC expression was upregulated in the dfr mutant, suggesting that DFR is a negative regulator of FLC. With respect to vernalization, Sheldon et al. (2006) showed that sequences within intron 1 and the activities of both VERNALIZATION1 (VRN1) and VERNALIZATION2 (VRN2) were required for efficient establishment of FLC repression; however, VRN1 and VRN2 were not required for maintenance of the repressed state during growth after the cold exposure. Moreover, SUPPRESSOR OF OVER-EXPRESSION OF CO 1 (SOC1), a downstream target of FLC, was quantitatively induced by vernalization in a reciprocal manner to FLC. Searle et al. (2006) show that FLC delays flowering by 1) repressing production in the leaf of at least two systemic signals, one of which is controlled by the RAF kinase inhibitor-like protein FT and 2) FLC expression in the meristem impairs response to the FT signal by directly repressing expression of the SOC1 MADS-box transcription factor and preventing up-regulation of the bZIP transcription factor FD. Circadian clock components TIMING OF CAB EXPRESSION1 (TOC1), GIGANTEA (GI), and the partially redundant genes CIRCADIAN CLOCK ASSOCIATED1 (CCA1) and LATE ELONGATED HYPOCOTYL (LHY) are affected by ambient temperatures. Gould et al. (2006) noted that the amplitude and peak levels increased for TOC1 and GI RNA rhythms as the temperature increased from 17 to 27°C, but they decrease for LHY; in contrast, as temperatures decreased from 17 to 12°C, CCA1 and LHY RNA rhythms increased in amplitude and peak expression level. Razem et al. (2006) used a biochemical approach to isolate a barley protein that has ABA-binding activity, named ABAP1, and investigated whether a homologue of ABAP1 functions in an ABA response in Arabidopsis. They show that an RNA-binding protein called FCA binds to ABA and is regulated by it, and that FCA is involved in a less well-studied function of ABA ­ the inhibition of flowering. The FCA protein is a component of the so-called autonomous flowering pathway, which reduces the activity of the flowering repressor FLC. These detailed studies about ABA further shed light on the ability of plants to survive a lack of water, extreme temperatures and such stresses as high salt levels. A TFL1 (TERMINAL FLOWER 1) homologue from grapevine (VvTFL1) was overexpressed in tobacco and Arabidopsis to confirm that it was functionally similar to TFL1 and not the close homologue FT: flowering was significantly delayed (Boss et al. 2006). One surprising result was that in some of the transgenic Arabidopsis lines the floral meristem became indeterminate and a new inflorescence emerged from within the developing silique. Authors concluded that VvTFL1 is a repressor of floral development. FT induces flowering while TFL1 represses flowering and the residues responsible for the opposite activities of FT and TFL1 were mapped by examining plants that overexpress chimeric proteins (Ahn et al. 2006). Vernalization is the process of promotion of flowering after exposure to prolonged periods of cold, and is needed by many plant species and grasses. Ciannamea et al. (2006) used cDNA microRNAs to try and quantify veranlization by analyzing the expression patterns of about 1,500 unique Lolium perenne genes. Of significance was their finding that three of the up-regulated

genes are homologous to members of the MADS box, CONSTANS-like and JUMONJI families of transcription factors, respectively. The latter two are novel genes not connected previously to vernalization-induced flowering. Members of the JUMONJI family of transcription factors have been shown to be involved in chromatin remodeling, suggesting that this molecular mechanism, as in Arabidopsis, plays a role in the regulation of the vernalization response in monocots. Increases (up to as much as 75%) in alternative pathway flux were found in in vivo sacred lotus (Nelumbo nucifera) receptacles when placed at temperatures 16°C to 20°C above ambient, possibly explaining heating in lotus; it was thought that it is unlikely that uncoupling proteins, which would have produced increased fluxes through the cytochrome pathway, contribute significantly to heating in this tissue (Watling et al. 2006). Thermogenesis, heating in flowers, floral furnaces and solar heating are all reviewed by Lamprecht et al. (2006). The environmental factors affecting dormancy induction of N. nucifera, which is widely cultivated in Japan as an ornamental, were studied by Masuda et al. (2006). The floral-nectary ultrastructure in Echinacea purpurea, a plant of horticultural and nutraceutical value, was addressed by Wist and Davis (2006). Phyllotaxis, the regular arrangement of lateral organs around a central axis, has been modelled by Smith et al. (2006) to produce distichous, decussate, and tricussate patterns, providing a plausible link between molecular mechanisms of morphogenesis and the geometry of phyllotaxis. Plant organ positioning may be mediated by localized concentrations of the plant hormone auxin, whose patterning in the SAM is in turn brought about by the subcellular polar distribution of the putative auxin efflux mediator, PIN1. Polarized transport in the formation of regular patterns was modeled by Jönsson et al. (2006) and by de Reuille et al. (2006). Ashman and Majetic (2006) review published data on heritabilities and genetic correlations for several classes of floral traits (primary sexual, attraction, mating system) in hermaphroditic plants. They also test predictions stemming from life history theory (eg, negative covariation between male-female traits and flower size-flower number), and ideas concerning the extent and pattern of genetic integration between flowers and leaves, and between the sexes of dioecious and gynodioecious species. Amoeboid bionts caused extensive areas of destruction and blocked flower organ development in Olea europaea L., `Santulhana' and `Conserva de Elvas' (Medeira et al. 2006). The flowering time of A. thaliana plants transformed with a tomato HAP5 (THAP5a) gene was reduced under warm long days (Ben-Naim et al. 2006). Mammalian proteins containing a methyl-CpG-binding domain (MBD) can decipher the epigenetic information encoded by DNA methylation, and integrate DNA methylation, modification of chromatin structure and repression of gene expression (Peng et al. 2006). One of the mutations in the A. thaliana MBD proteins resulted in significantly earlier flowering than wild-type plants. The expression of FLC, a major repressor of Arabidopsis flowering, was markedly attenuated by the AtMBD9 mutations. Early flowering was induced inn Arabidopsis plants transformed with the willow (Salix discolor) SAP1 gene

(Fernando and Zhang 2006). The expression patterns of this gene in various parts of the male reproductive buds of S. discolor suggest its involvement in the formation of the inflorescence meristems, bracts, and floral meristems. Contrary to previous results, in which theobroxide, an active fungal compound, induced flower bud formation in P. nil under non-inductive long-day conditions, Gao X-Q et al. (2006) found a reduction of the stem length, along with the induction of flower buds, in theobroxide-treated and short-day-grown P. nil plants.

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benzenoid biosynthesis in petunia flowers. Trends in Plant Science 11, 1-4 Szentmihályi K, Illés V, Pintér M, Then M (2006) Flowering plants in the art of perfume therapy (chemical aspect). In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol IV, Global Science Books, Ltd, UK, pp 328-335 Tholl D, Boland W, Hansel A, Loreto F, Röse USR, Schnitzler JP (2006) Practical approaches to plant volatile analysis. The Plant Journal 45, 540-560 van Schie CCN, Haring MA, Schuurink RC (2006) Regulation of terpenoid and benzenoid production in flowers. Current Opinion in Plant Biology 9, 203-208

Flower fragrance and scent In a bid to expand the genetic resource base for P. hybrida breeding, Nakamura et al. (2006) identified several diurnally released volatile compounds from 40 commenrcial petunia cultivars using a solid-phase micro-extraction technique coupled with GC­MS. They identified the main floral fragrance to be iso-eugenol from solid deep-blue flowering cvs. while high level methylbenzoate- and/or benzylbenzoate-releasing cvs were also identified. Volatile production depends on substrate availability. This fact was crisply demonstarted by experiments conducted by Guterman et al. (2006) in which transgenic petunia plants expressing the rose alcohol acetyltransferase (RhAAT) gene could use phenylethyl alcohol and benzyl alcohol fed in vitro to produce the corresponding acetate esters, not generated by control flowers. Esters are in fact important contributors to the aroma of numerous flowers and fruits. van Schie et al. (2006) and Schuurink et al. (2006) review the regulation of the floral volatiles benzenoids and terpenoids in flowers. Scalliet et al. (2006a) suggest that up-regulation of OOMT (Orcinol O-methyltransferase) gene expression may have been a critical step in the evolution of scent production in roses. OOMT 1 and 2 catalyze the last two steps of the biosynthetic pathway leading to the phenolic methyl ether 3,5-dimethoxytoluene (DMT), the major scent compound of many rose (Rosa x hybrida) varieties. Scalliet et al. (2006b) review flower scent in Volume I of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. Volatile analysis has been reviewed by Szentmihályi et al. (2006) and Tholl et al. (2006), and electronic noses by Lozano-Rogado (2006).

Guterman I, Masci T, Chen X, Negre F, Pichersky E, Dudareva N, Weiss D, Vainstein A (2006) Generation of phenylpropanoid pathway-derived volatiles in transgenic plants: rose alcohol acetyltransferase produces phenylethyl acetate and benzyl acetate in petunia flowers. Plant Molecular Biology 60, 555-563 Lozano-Rogado J (2006) New technology in sensing odours: from Human to artificial noses. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol IV, Global Science Books, Ltd, UK, pp 152-161 Nakamura K, Matsubara K, Watanabe H, Kokubun H, Ueda Y, Oyama-Okubo N, Nakayama M, Ando T (2006) Identification of Petunia hybrida cultivars that diurnally emit floral fragrances. Scientia Horticulturae 108, 61-65 Scalliet G, Lionnet C, Bechec ML, Dutron L, Magnard JL, Baudino S, Bergougnoux V, Jullien F, Chambrier P, Vergne P, Dumas C, Cock JM, Hugueney P (2006a) Role of petal-specific Orcinol O-Methyltransferases in the evolution of rose scent. Plant Physiology 140, 18-29 Scalliet G, Baudino S, Cock JM, Hugueney P (2006b) Model plants and functional genomic approaches applied to the characterization of genes involved in floral scent biosynthesis. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 293-299 Schuurink RC, Haring MA, Clark DG (2006) Regulation of volatile

Genetic transformation and transgenes An effective biolistic protocol, associated with equally highly regenerative somatic embryogenic protocols were developed for turmeric (Curcuma longa L.). Transformants contained the bar and gusA genes each driven by the maize ubiquitin promoter, whose transformation events were confirmed by PCR, GUS assay and resistance to glufosinate (Shirgurkar et al. 2006). More information about Curcuma has been recently reviewed in a secondary metabolite context by Xu et al. (2006). Roh et al. (2006) conducted trials to assess the capacity of 16 new Curcuma genetic resources to be used as pot plants and cut flowers. Quorum-sensing components, as found in Gram-negative bacteria such as Agrobacterium tumefaciens, to monitor their own population density by utilizing members of the N-acyl homoserine lactone family as inducers and a transcriptional activator as its receptor. One such A. tumefaciens component, the 3-oxooctanyl-L-homoserine lactone [OOHL] binds to its receptor, TraR, and recognizes its specific cis-element, the tra box. This novel transgene reporter construct induced reporter gene expression in moss (Physcomitrella patens), barley (Hordeum vulgare), and carrot (Daucus carota) cells, as well as in transgenic A. thaliana seedlings (You et al. 2006). A systems approach to gene identification and gain-of-function phenotype screens in transgenic A. thaliana plants was used to understand the processes regulated by the CLAVATA3 (CLV3)/ESR (CLE) ligand gene family, which are known to play key roles in the regulation of plant growth, development, and environmental responses (Strabala et al. 2006). Four new CLE family members in the A. thaliana genome sequence were identified and their relative transcript levels in various organs were determined. Primary results are: 1) overexpression of CLV3 and the 17 CLE genes we tested resulted in premature mortality and/or developmental timing delays in transgenic Arabidopsis plants; 2) overexpression of 10 CLE genes and the CLV3 positive control resulted in arrest of growth from the shoot apical meristem (SAM); 3) overexpression of nearly all the CLE genes and CLV3 resulted in either inhibition or stimulation of root growth; 4) CLE4 expression reversed the SAM proliferation phenotype of a clv3 mutant to one of SAM arrest. Dwarf plants resulted from overexpression of five CLE genes; 5) overexpression of new family members CLE42 and CLE44 resulted in distinctive shrub-like dwarf plants lacking apical dominance. Photoactivatable fluorescent proteins (PAFPs) are a relatively new class of proteins that have been developed in the last few years capable of pronounced light-induced spectral changes. Whereas previously-derived green fluorescent protein (GFP) protein had been isolated form a jellyfish, a new monomeric PAFP, Dendra, derived from octocoral Dendronephthya sp. and capable of 1,000- to 4,500-fold photoconversion from green to red fluorescent states in response

to either visible blue or UV-violet light, was isolated, screened and tested by Gurskaya et al. (2006). Dendra represents the first PAFP, which is simultaneously monomeric, efficiently matures at 37°C, demonstrates high photostability of the activated state, and can be photoactivated by a common, marginally phototoxic, 488-nm laser line. The authors show the suitability of Dendra for protein labeling and tracking to quantitatively study dynamics of fibrillarin and vimentin in mammalian cells, but the possibilities for plant cell application are tremendous. In a related study, Pédelacq et al. (2006) generated a robustly folded version of GFP, called 'superfolder' GFP, that folds well even when fused to poorly folded polypeptides. 'Superfolder' GFP was created since existing variants of GFP often misfold when expressed as fusions with other proteins. The use of GFP and other novel fluorescent proteins as markers in genetic engineering and for tracking of nucleic acids has been reviewed by Mercuri et al. (2006), Dirks and Tanke (2006) and by Stewart (2006). Transgenic plants expressing insecticidal Cry proteins derived from Bacillus thuringiensis (Bt) is increasing worldwide. In order to adopt Bt crops, integrated pest management systems (incorporating the correct regulatory frameworks) should consider their potential impact on nontarget organisms including biological control organisms. These issues are discussed in detail by Romeis et al. (2006). Cry expressing chrysanthemums, wth detailed protocols, are outlined by Shinoyama et al. (2006). As a consequence of plant transformation by disarmed Agrobacterium tumefaciens strains, gene expression is regulated through microRNAs (miRNAs) and antiviral defense through small interfering RNAs (siRNAs), both aspects of RNA silencing (Valencia-Sanchez et al. 2006); also reviewed by Brodersen and Voinnet (2006). Dunoyer et al. (2006) show for the first time that siRNAs corresponding to transferred-DNA oncogenes initially accumulate in virulent A. tumefaciens-infected tissues and that RNA interference-deficient plants are hypersusceptible to the pathogen. Successful infection relies on a potent antisilencing state established in tumors whereby siRNA synthesis is specifically inhibited. This inhibition has only modest side effects on the miRNA pathway, shown here to be essential for disease development. The conservation and divergence of miRNAs, a class of newly identified, small, non-coding RNAs that play versatile and important roles in post-transcriptional gene regulation, have been discussed by Zhang et al. (2006) and reviewed by Meyers et al. (2006). Schwab et al. (2006) designed artificial miRNAs (amiRNAs) to target individual genes or groups of endogenous genes and found that amiRNAs make an effective tool for specific gene silencing in plants, especially when several related, but not identical, target genes need to be downregulated. The genetic transformation of forage and turfgrasses has been reviewed by Wang and Ge (2006). The biolistic and Agrobacterium-mediated transformation of turfgrasses have also been dealt with in the Genetic Engineering section of Volume II of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues, while the mechanisms of infection by this natural transforming agent have been reviewed by Tzfira and Citovsky (2006). Cañizares et al. (2006) developed combined transgene/virus vector systems for the expression of heterologous proteins in plants based on the bipartite RNA plant virus, cowpea mosaic

virus (CPMV), and involve the amplification of integrated copies of either full-length or deleted versions of RNA-2 carrying a foreign gene. Hefferon (2006) and Chung et al. (2006) reviews the use of viruses for protein expression studies. Three natural somatic mutations at codon 304 of the phytoene desaturase gene (pds) of Hydrilla verticillata provide resistance to the herbicide fluridone. Arias et al. (2006) capitalized upon this finding to develop transgenic A. thaliana plants harbouring one of four selected mutations that conferred resistance to varying degrees to fluridone, beflubutamid, picolinafen and diflufenican. Authors further claim that since Thr304 pds is of plant origin, it could become more acceptable than other selectable markers for use in genetically modified food. Buhot et al. (2006) explored the similarities and differences between the eubacterial and the plastid eubacterial type transcription systems to create a hybrid transcription system in which the transgene is placed under the control of a eubacterial promoter which does not exist in the plastid genome and which is not recognized by the plastid endogenous transcriptional machinery. Biosafety factors that shuld be considered in genetically modified trees, particularly Populus spp. are dealt with in a review by Hoenicka and Fladung (2006). Lee and Natesan (2006) present mathematical models and empirical experimental evidence suggesting that genetic approaches have the potential to effectively prevent transgenes from incorporating into wild relatives and becoming established in wild populations that are not reproductively isolated from genetically engineered crops. Smith and Anderson (2006) present details of transgenic strategies to prevent the escape of transgenes into wild populations. Jank et al. (2006) propose physically dividing GM-containing and GM-free zones to avoid contamination. In order to obtain a continuous set of expression levels with only slight increments in strength to cover a specific window around the wild-type expression level of the studied gene, it is recommended that a promoter library be established. Guidelines for promoter library creation and utilization are detailed by Hammer et al. (2006).

Arias RS, Dayan FE, Michel A, J'Lynn H, Scheffler BE (2006) Characterization of a higher plant herbicide-resistant phytoene desaturase and its use as a selectable marker. Plant Biotechnology Journal 4, 263-273 Brodersen P, Voinnet O (2006) The diversity of RNA silencing pathways in plants. Trends in Genetics 22, 268-280 Buhot L, Horvàth E, Medgyesy P, Lerbs-Mache S (2006) Hybrid transcription system for controlled plastid transgene expression. The Plant Journal 46, 700-707 Cañizares MC, Liu L, Perrin Y, Tsakiris E, Lomonossoff GP (2006) A bipartite system for the constitutive and inducible expression of high levels of foreign proteins in plants. Plant Biotechnology Journal 4, 183-193 Chung S-M, Vaidya M, Tzfira T (2006) Agrobacterium is not alone: gene transfer to plants by viruses and other bacteria. Trends in Plant Science 11, 1-4 Dirks RW, Tanke HJ (2006) Advances in fluorescent tracking of nucleic acids in living cells. BioTechniques 40, 489-496 Dunoyer P, Himber C, Voinnet O (2006) Induction, suppression and requirement of RNA silencing pathways in virulent Agrobacterium tumefaciens infections. Nature Genetics 38, 258-263 Gurskaya NG, Verkhusha VV, Shcheglov AS, Staroverov DB, Chepurnykh TV, Fradkov AF, Lukyanov S, Lukyanov KA (2006) Engineering of a monomeric green-to-red photoactivatable fluorescent protein induced by blue light. Nature Biotechnology 24, 461-465 Hammer K, Mijakovic I, Jensen PR (2006) Synthetic promoter libraries ­ tuning of gene expression. Trends in Biotechnology 24, 53-55 Hefferon KL (2006) Novel approaches to protein expression using plant virus expression vectors. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st

ed) vol II, Global Science Books, Ltd, UK, pp 30-40 Hoenicka H, Fladung M (2006) Biosafety in Populus spp. and other forest trees: from non-native species to taxa derived from traditional breeding and genetic engineering. Trees - Structure and Function 20, 131-144 Jank B, Rath J, Gaugitsch H (2006) Co-existence of agricultural production systems. Trends in Biotechnology 24, 198-200 Lee D, Natesan E (2006) Evaluating genetic containment strategies for transgenic plants. Trends in Biotechnology 24, 109-114 Mercuri A, De Benedetti L, Bruna S, Schiva T, Alberti S (2006) Fluorescent molecules in plant biotechnology. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 60-65 Meyers BC, Souret FF, Lu C, Green PJ (2006) Sweating the small stuff: microRNA discovery in plants. Current Opinion in Biotechnology 17, 139-146 Pédelacq J-D, Cabantous S, Tran T, Terwilliger TC, Waldo GS (2006) Engineering and characterization of a superfolder green fluorescent protein. Nature Biotechnology 24, 79-88 Roh MS, Lawson R, Lee JS, Suh JK, Criley RA, Apavatjrut P (2006) Evaluation of Curcuma as potted plants and cut flowers. The Journal of Horticultural Science and Biotechnology 81, 63-71 Romeis J, Meissle M, Bigler F (2006) Transgenic crops expressing Bacillus thuringiensis toxins and biological control. Nature Biotechnology 24, 63-71 Shinoyama H, Anderson N, Furuta H, Mochizuki A, Nomura Y, Singh RP, Datta SK, Wang B-C, Teixeira da Silva JA (2006) Chrysanthemum biotechnology. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 140-163 Shirgurkar MV, Naik VB, von Arnold S, Nadgauda RS, Clapham D (2006) An efficient protocol for genetic transformation and shoot regeneration of turmeric (Curcuma longa L.) via particle bombardment. Plant Cell Reports 25, 112-116 Schwab R, Ossowski S, Riester M, Warthmann N, Weigel D (2006) Highly specific gene silencing by artificial microRNAs in Arabidopsis. The Plant Cell 18, 1121-1133 Smith AG, Anderson NO (2006) Engineered sterility for non-native plant invaders. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 232-239 Stewart NC Jr (2006) Go with the glow: fluorescent proteins to light transgenic organisms. Trends in Biotechnology 24, 155-162 Strabala TJ, O'Donnell PJ, Smit AM, Ampomah-Dwamena C, Martin EJ, Netzler N, Nieuwenhuizen NJ, Quinn BD, Foote HCC, Hudson KR (2006) Gain-of-function phenotypes of many CLAVATA3/ESR genes, including four new family members, correlate with tandem variations in the conserved CLAVATA3/ESR domain. Plant Physiology 140, 1331-1344 Tzfira T, Citovsky V (2006) Agrobacterium-mediated genetic transformation of plants: biology and biotechnology. Current Opinion in Biotechnology 17, 147-154 Valencia-Sanchez MA, Liu J, Hannon GJ, Parker R (2006) Control of translation and mRNA degradation by miRNAs and siRNAs. Genes and Development 20, 515-524 Wang Z-Y, Ge Y (2006) Recent advances in genetic transformation of forage and turf grasses. In Vitro Cellular and Developmental Biology - Plant 42, 1-18 Xu Q, Teixeira da Silva JA, Kong L (2006) Advance of biotechnology used in Curcuma plant research. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol IV, Global Science Books, Ltd, UK, pp 517-528 You Y-S, Marella H, Zentella R, Zhou Y, Ulmasov T, Ho T-HD, Quatrano RS (2006) Use of bacterial quorum-sensing components to regulate gene expression in plants. Plant Physiology 140, 1205-1212 Zhang B-H, Pan X, Cannon CH, Cobb GP, Anderson TA (2006) Conservation and divergence of plant microRNA genes. The Plant Journal 46, 243-259

Li et al. (2006) claim that T-DNA insertions are not randomly distributed in the A. thaliana genome and that there are still a fairly high number of annotated genes without T-DNA insertions. This information, obtained from flanking sequence tag (FST) data reveals a limitation of T-DNA in saturation mutagenesis. Nakano et al. (2006) provide a full overview of the ERF gene family in Arabidopsis and rice (Oryza sativa L. subsp. japonica), including the gene structures, phylogeny, chromosome locations, and conserved motifs. Genes in the ERF family encode transcriptional regulators with a variety of functions involved in the developmental and physiological processes in plants. Gene targeting has been extensively reviewed by Kumar et al. (2006).

Geisler-Lee J, Geisler M, Coutinho PM, Segerman B, Nishikubo N, Takahashi J, Aspeborg H, Djerbi S, Master E, Andersson-Gunnerås S, Sundberg B, Karpinski S, Teeri TT, Kleczkowski LA, Henrissat B, Mellerowicz EJ (2006) Poplar carbohydrate-active enzymes. Gene identification and expression analyses. Plant Physiology 140, 946-962 Klimmek F, Sjödin A, Noutsos C, Leister D, Jansson S (2006) Abundantly and rarely expressed Lhc protein genes exhibit distinct regulation patterns in plants. Plant Physiology 140, 793-804 Kumar S, Franco M, Allen GC (2006) Gene targeting: development of novel systems for genome engineering in plants. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol IV, Global Science Books, Ltd, UK, pp 84-98 Li Y, Rosso MG, Ülker B, Weisshaar B (2006) Analysis of T-DNA insertion site distribution patterns in Arabidopsis thaliana reveals special features of genes without insertions. Genomics 87, 645-652 Nakano T, Suzuki K, Fujimura T, Shinshi H (2006) Genome-wide analysis of the ERF gene family in Arabidopsis and rice. Plant Physiology 140, 411-432

Heat tolerance A novel heat-shock (HS) and heat-stress-associated protein, Hsa32, which is highly conserved in land plants but absent in most other organisms, is produced in response to gene activation by HS at the transcriptional level in moss (Physcomitrella patens), A. thaliana, and rice (O. sativa) and is required maintenance of acquired thermotolerance rather than for induction (Charng et al. 2006). Significant results of this study include: a) Disruption of Hsa32 by T-DNA insertion did not affect growth and development under normal conditions; b) acquired thermotolerance in the knockout line was lost only after a long recovery period (>24 h) after acclimation HS treatment, when a severe HS challenge killed the mutant but not the wild-type plants; c) similar results were obtained in Arabidopsis transgenic plants with Hsa32 expression suppressed by RNA interference.

Charng Y-Y, Liu H-C, Liu N-Y, Hsu F-C, Ko S-S (2006) Arabidopsis Hsa32, a novel heat shock protein, is essential for acquired thermotolerance during long recovery after acclimation. Plant Physiology 140, 1297-1305

Genomic analyses Klimmek et al. (2006) analyzed gene regulation of the Lhc supergene family in poplar (Populus spp.) and A. thaliana using digital expression profiling (tissue-specific, environmental, and developmental Lhc expression patterns). Geisler-Lee et al. (2006) identified more than 1,600 genes encoding carbohydrate-active enzymes (CAZymes) in the Populus trichocarpa genome based on sequence homology, annotated, and grouped into families of glycosyltransferases, glycoside hydrolases, carbohydrate esterases, polysaccharide lyases, and expansins. Apart from their several fascinating findings, they concluded that profound changes in CAZyme transcriptomes in different poplar tissues demonstrated some key differences in CAZyme genes and their regulation between herbaceous and woody plants.

Hormones (plant) Mitchum et al. (2006) show that AtGA3ox1 and AtGA3ox2 are responsible for the synthesis of bioactive GAs during vegetative growth, but that they are dispensable for reproductive development. GA 3-oxidase is a class of 2-oxoglutarate-dependent dioxygenases that catalyzes the conversion of precursor GAs to their bioactive forms, thereby playing a direct role in determining the levels of bioactive GAs in plants.

Mitchum MG, Yamaguchi S, Hanada Ai, Kuwahara A, Yoshioka Y, Kato T, Tabata S, Kamiya Y, Sun T-P (2006) Distinct and overlapping roles of

two gibberellin 3-oxidases in Arabidopsis development. The Plant Journal 45, 804-818

Improved flowering The application of GA3, applied as a spray at 375 mg/l resulted in earlier flowering in Iris nigricans (black iris); in contrast a drench with 1 mg/l GA3 resulted in delyed flowering; the same drench however resulted in cut flower sem elongation which were more rigid (Al-Khassawneh et al. 2006). Paclobutrazol and chlormequat were both effective in reducing plant height for pot plant production, although some negative effects were observed in flowering. Khan and Chaudhry (2006) concluded that inhibitory effects of heavy metals on flowering in Cucumis sativus and Momordica charantia were partially restored by phytohormones since: a) GA3 applied at 400 ppm caused precocious flowering, increasing the number of pistillate and staminate flowers; b) application of Pb(NO3)2 and HgCl2 caused significant delay in flowering, consequently leading to reduction in number of flowers; c) when GA3 was applied with both these heavy metals, there was reduction in staminate and pistillate flowers, showing the dominant effect of GA3. Correct pistil development in Arabidopsis has been attributed to the novel PEPPER or PEP gene, which codes for a polypeptide with K-homology (KH) RNA-binding modules (Ripoll et al. 2006).

Al-Khassawneh NM, Karam NS, Shibli RA (2006) Growth and flowering of black iris (Iris nigricans Dinsm.) following treatment with plant growth regulators. Scientia Horticulturae 107, 187-193 Khan AS, Chaudhry NY (2006) GA3 improves flower yield in some cucurbits treated with lead and mercury. African Journal of Botechnology 5, 88-94 Ripoll JJ, Ferrándiz C, Martínez-Laborda A, Vera A (2006) PEPPER, a novel K-homology domain gene, regulates vegetative and gynoecium development in Arabidopsis. Developmental Biology 289, 346-359

in soil-less culture. Scientia Horticulturae 108, 195-193 Son JE, Oh MM, Lu YJ, Kim KS, Giacomelli GA (2006) Nutrient-flow wick culture system for potted plant production: System characteristics and plant growth. Scientia Horticulturae 107, 392-398

Irrigation The growth performance of Kalanchoe blossfeldiana cv. New Alter was determined in a new nutrient-flow wick culture (NFW) system that was developed and compared with other subirrigation systems, such as an ebb and flow culture (EBB) system and a nutrient-stagnant wick culture (NSW) system (Son et al. 2006). Advantages of the NFW system include simplicity, water-saving, increased dissolved oxygen, and low salinity. Secondary waste water was successfully applied in the irrigation of Rosa hybrida in soilless culture (Nirit et al. 2006). This is particularly useful in arid areas where there is a shortage of water. In this important study, two soilless media, perlite and choir (coconut fibers) were used. NO apparent change in vegetative morphology, flower shape or colour, or even disease susceptibility were detected, even though it is known that flower color, shelf life and resistance to diseases may be affected by the chemical composition of the irrigation water (e.g. Gerasopoulos and Chebli 1999). Excess salts (as found in wastewaters) have been shown to activate genes usually induced by ethylene (Fujimoto et al. 2000).

Fujimoto SY, Ohta M, Usui A, Shinshi H, Ohme Takagi M (2000) Arabidopsis ethylene-responsive element binding factors act as transcript ional activators or repressors of GCC box-mediated gene expression. Plant Cell 12, 393-404 Gerasopoulos D, Chebli B (1999) Effects of pre- and postharvest calcium applications on the vase life of cut gerberas. The Journal of Horticultural Science and Biotechnology 74, 78-81 Nirit B, Asher BT, Haya F, Pini S, Ilona R, Amram C, Marina I (2006) Application of treated wastewater for cultivation of roses (Rosa hybrida)

Light, lighting, and light-sensing The transition from light to dark (and vice versa) is one of the areas of photomorphology that remians most poorly studied. Even though many sdtudies exist characterizing growth, physiology and gene regulation in either the light or dark, this "transition" period remained fairly elusive until Kim and von Arnim (2006) provided some more light on the topic. Microarray expression analyses (by expression clustering and gene ontology) identified ~790 responsive genes implicated in diverse cellular processes. Authors classified the the early response to darkness to have distinct clusters: early transient, early sustained and late response. Of interest is the fact that COP1 (constitutive photomorphogenic 1), the repressor of photomorphogenesis, is not a chief regulator of the early response to darkness, in contrast to its well-established role during long-term dark adaptation and etiolation. Abscisic acid (ABA) signaling was also shown to play a prominent role in the early response to darkness. Fibrillins are lipid-binding proteins of plastids that are induced under abiotic stress conditions (e.g. photo-stress). Plants generate ABA as an endogenous signal in response to environmental stress, and Yang et al. (2006) showed that ABA treatment and fibrillin accumulation enhance the tolerance of photosystem II toward light stress-triggered photoinhibition in Arabidopsis; ABA induces fibrillin accumulation, and the ABA response regulators ABI1 and ABI2 regulate fibrillin expression. Furihata et al. (2006) show that the ABA-dependent multisite phosphorylation of AREB1 regulates its own activation in plants. AREB1 is a bZIP-type transcription factor that binds an ABA-responsive cis-acting element (ABRE) and transactivate downstream gene expression in Arabidopsis. The importance of ABA and the transcriptional regulator ABA-insensitive4 (ABI4) in sugar response pathways is highlighted by Rook et al. (2006). CONSTANS-LIKE3 (COL3) is a novel interaction partner of COP1, or CONSTITUTIVE PHOTOMORPHOGENIC1, an E3 ubiquitin ligase that represses photomorphogenesis in the dark (Datta et al. 2006). COL3 can also promote lateral root development independently of COP1 and also function as a daylength-sensitive regulator of shoot branching. The blue light (BL) photoreceptors for phototropism, chloroplast relocation, stomatal opening and leaf flattening in A. thaliana are phototropins 1 and 2 (phot1 and phot2). Using phot1phot2 double mutant Arabidopsis plants with constructs encoding translationally fused phot2:green fluorescent protein, Kong et al. (2006) showed that a kinase domain is essential for the Golgi localization of phot2 and that the BL-induced Golgi localization of phot2 may be one of important signaling steps in the phot2 signal transduction pathway. In related comparative studies between Arabidopsis Landsberg erecta and Cape Verde Islands accessions, phase, which reflects the entrained relationship between the clock and the external cycle was studied by Darrah et al. (2006). Four quantitative trait loci (QTL) were found with major effects on circadian phase, one of which, located on chromosome 5 contained SIGNALING IN RED LIGHT REDUCED 1 and PSEUDORESPONSE REGULATOR 3, both genes that affect the circadian clock. Previously unknown polymorphisms were

found in both genes, making them candidates for the effect on phase. A moving lighting system consisting of high pressure sodium (HPS) lamps was shown to increase the photosynthetic capacity (represented by light saturated net CO2 exchange rate (NCER) (Asat), light- and CO2-saturated rate of NCER (Amax), maximum rate of Rubisco carboxylation (Vcmax), maximum rate of electron transport (Jmax) and rate of triose phosphate utilization) of Gerbera jamesonii "Festival" (Zheng et al. 2006). Despite this, in situ leaf NCER and stomatal conductance, leaf chlorophyll content index, leaf area, leaf thickness, fresh weight of plants were significantly lower under moving lighting than under stationary lighting. Reduction in the growth of plants under moving lighting may have been caused by the overall lower light use efficiency of leaves under moving lighting than those under stationary lighting or by the slower response time of the photosynthetic system compared to the rate of change in light intensity under moving lighting. Kevei et al. (2006) conducted a large-scale genetic screen that identified additional clock-affecting loci. This study is important since none of the known components of feedback loops wiithin the A. thaliana circadian system is completely understood. A clearer understanding of ZEITLUPE (ZTL), a gene implicated in regulated protein degradation, was provided. ztl mutations affect both circadian and developmental responses to red light, possibly through ZTL interaction with PHYTOCHROME B (PHYB). Allen et al. (2006) report the isolation the mutant gil1 (for gravitropic in the light) in which hypocotyls continue to grow upwards after exposure of seedlings to R or FR light. The novel GIL1 gene is necessary for light-dependent randomization of hypocotyl growth orientation. GIGANTEA (GI) is a key regulator of photoperiodic flowering in Arabidopsis and encodes a protein with no domains of known biochemical function. Expression of GI mRNA is controlled by the circadian clock, but GI protein accumulation had not been previously investigated until David et al. (2006) generated plants that produced functional epitope-tagged GI to enabled them to track the protein through the daily cycle. They found that accumulation was modulated by day length as well as by phase-specific factors. Green light reversal of blue light-stimulated stomatal opening was discovered in isolated Arabidopsis stomata of intact leaves, but this response (i.e. stomatal sensitivity to green light) was observed only in the morning, which coincided with the use of potassium as a guard cell osmoticum (Talbott et al. 2006). Chen and Ni (2006) discovered a long hypocotyl mutant under red and far-red (FR) light, rfi2-1 (red and far-red insensitive 2 to 1) that was also impaired in phytochrome-mediated end-of-day FR light response, cotyledon expansion, FR light block of greening, and light-induced expression of CHLOROPHYLL A/B BINDING PROTEIN 3 and CHALCONE SYNTHASE. Authors conclude that RFI2 reveals a signaling step that mediates phytochrome control of seedling deetiolation. Several important aspects of light in flowering induction have been discussed in Volume I of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues, while light management for ornamentals is detailed by Pérez et al. (2006).

Allen T, Ingles PJ, Praekelt U, Smith H, Whitelam GC (2006) Phytochrome-mediated agravitropism in Arabidopsis hypocotyls requires GIL1 and confers a fitness advantage. The Plant Journal 46, 641-648 Chen M, Ni M (2006) RED AND FAR-RED INSENSITIVE 2, a ring-domain zinc finger protein, mediates phytochrome-controlled seedling deetiolation responses. Plant Physiology 140, 457-465 Darrah C, Taylor BL, Edwards KD, Brown PE, Hall A, McWatters HG (2006) Analysis of phase of LUCIFERASE expression reveals novel circadian quantitative trait loci in Arabidopsis. Plant Physiology 140, 1464-1474 Datta S, Hettiarachchi GHCM, Deng X-W, Holm M (2006) Arabidopsis CONSTANS-LIKE3 is a positive regulator of red light signaling and root growth. The Plant Cell 18, 70-84 David KM, Armbruster U, Tama N, Putterill J (2006) Arabidopsis GIGANTEA protein is post-transcriptionally regulated by light and dark. FEBS Letters 580, 1193-1197 Furihata T, Maruyama K, Fujita Y, Umezawa T, Yoshida R, Shinozaki K, Yamaguchi-Shinozaki K (2006) Abscisic acid-dependent multisite phosphorylation regulates the activity of a transcription activator AREB1. Proceedings of the National Academy of Sciences USA 103, 1988-1993 Kevei E, Gyula P, Hall A, Kozma-Bognár L, Kim W-Y, Eriksson ME, Tóth R, Hanano S, Fehér B, Southern MM, Bastow RM, Viczián A, Hibberd V, Davis SJ, Somers DE, Nagy F, Millar AJ (2006) Forward genetic analysis of the circadian clock separates the multiple functions of ZEITLUPE. Plant Physiology 140, 933-945 Kim B-H, von Arnim AG (2006) The early dark-response in Arabidopsis thaliana revealed by cDNA microarray analysis. Plant Molecular Biology 60, 321-342 Kong S-G, Suzuki T, Tamura K, Mochizuki N, Hara-Nishimura I, Nagatani A (2006) Blue light-induced association of phototropin 2 with the Golgi apparatus. The Plant Journal 46, 994-1005 Pérez M, Teixeira da Silva JA, Lao MT (2006) Light management in ornamental crops. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol IV, Global Science Books, Ltd, UK, pp 683-695 Rook F, Hadingham SA, Li Y-H, Bevan MW (2006) Sugar and ABA response pathways and the control of gene expression. Plant, Cell and Environment 29, 426-434 Talbott LD, Hammad JW, Harn LC, Nguyen VH, Patel J, Zeiger E (2006) Reversal by green light of blue light-stimulated stomatal opening in intact, attached leaves of Arabidopsis operates only in the potassium-dependent, morning phase of movement. Plant and Cell Physiology 47, 332-339 Yang Y, Sulpice R, Himmelbach A, Meinhard M, Christmann A, Grill E (2006) Fibrillin expression is regulated by abscisic acid response regulators and is involved in abscisic acid-mediated photoprotection. Proceedings of the National Academy of Sciences USA 103, 6061-6066 Zheng Y, Blom T, Dixon M (2006) Moving lamps increase leaf photosynthetic capacity but not the growth of potted gerbera. Scientia Horticulturae 107, 380-385

Marker gene removal Tinoco et al. (2006) could successfully use -radiation to physically remove selective marker genes previously introduced into the soybean genome. Experiments were conducted based on the fact that ionizing radiation can generate chromosome breakage whose repair leads to mutations, many of which involve deletions. Althopugh plants were phenotypically normal, the possibility that novel mutations might have been introduced by the use of -rays was not discussed. Marker gene removal has been reviewed by Tian in Volume II of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues.

Tinoco ML, Vianna GR, Abud S, Souza PIM, Rech EL, Aragão FJL (2006) Radiation as a tool to remove selective marker genes from transgenic soybean plants. Biologia Plantarum 50, 146-148

Methods (novel) Current methods of RNA analysis on microchops frequently discriminate against structured and/or small RNA species, and to overcome this problem, Hu et al. (2006) established a method in which unmodified RNA is hybridized directly to DNA microarrays and detected with the high-affinity, nucleotide sequence-independent, DNA/RNA hybrid-specific mouse monoclonal antibody S9.6. Subsequent reactions with a fluorescently-labeled anti-mouse IgG antibody or biotin-labeled anti-mouse IgG together with fluorescently labeled streptavidin produces a signal that can be measured in a standard microarray

scanner. Microarrays have been reviewed by Clarke and Zhu (2006). `Footprinting' are assays in which ligand binding or structure formation protects polymers such as nucleic acids and proteins from either cleavage or modification; this analysis method allows the accessibility of individual residues to be mapped in solution and equilibrium and time-dependent footprinting links site-specific structural information with thermodynamic and kinetic transitions. Shcherbakova et al. (2006) describe a novel method of millisecond time-resolved ·OH footprinting based on the Fenton reaction, Fe(II) + H2O2 Fe(III) + ·OH + OH­. They claim that this method can be implemented in laboratories using widely available three-syringe quench flow mixers and inexpensive reagents to study local changes in the solvent accessibility of DNA, RNA and proteins associated with their biological function. Hasterok et al. (2006) modified a standard method of fluorescence in situ hybridisation (FISH) in which a combination of several substrates and probes on single microscope slides enabled more accurate comparisons of the distribution and abundance of chromosomal sequences and improves the relatively low throughput of standard FISH methods. This has great application for plant breeders, and the importance os staining techniques has been reviewed and analyzed in Volume I of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. In order to overcome the difficulties in introducing Ca2+-sensitive fluorescent dyes ­ useful for measuring environmental and developmental stimuli ­ into plant cells, Bothwell et al. (2006) adapted biolistic techniques to load Ca2+-sensitive dyes into guard cells of the flowering plant, Commelina communis, cells of the green alga Chlamydomonas reinhardtii, and zygotes of the brown alga, Fucus serratus. This will be useful in conjunction with single-cell experiments as described by Peng et al. (2006). Microwave radiation, a thermal weed control method, causes dielectric heating of plant tissue water that eventually kills the plant. Effective control of weeds in Abutilon theophrasti, Panicum miliaceum, lucerne and oilseed rape pure stands was shown (Sartorato et al. 2006). Readers are referred to Nucleic Acids Research and BioTechniques which contain excellent, novel techniques, many of which are applicable to plant science research. The preparation of protoplasts from pollen was effectively demonstrated by Fang et al. (2006) using Pinus bungeana and Picea wilsonii intact pollen grains. Incubation with gentle agitation in a solution of 2% cellulase R-10, 1.5% macerozyme R-10, 15% sucrose, 0.01% H3BO3, and 0.01% CaCl2 resulted in a 70% liberation rate.

Bothwell JHF, Brownlee C, Hetherington AM, Ng CKY, Wheeler GL, McAinsh MR (2006) Biolistic delivery of Ca2+ dyes into plant and algal cells. The Plant Journal 46, 327-335 Clarke JD, Zhu T (2006) Microarray analysis of the transcriptome as a stepping stone towards understanding biological systems: practical considerations and perspectives. The Plant Journal 45, 630-650 Fang K, Zhang L, Lin J (2006) A rapid, efficient method for the mass production of pollen protoplasts from Pinus bungeana Zucc. ex Endl. and Picea wilsonii Mast. Flora - Morphology, Distribution, Functional Ecology of Plants 201, 74-80 Hasterok R, Dulawa J, Jenkins G, Leggett M, Langdon T (2006) Multi-substrate chromosome preparations for high throughput comparative FISH. BMC Biotechnology 6, 20 Hu Z-L, Zhang A, Storz G, Gottesman S, Leppla SH (2006) An antibody-based microarray assay for small RNA detection. Nucleic Acids Research 34, e52

Peng XYL, Li PCH, Teixeira da Silva JA (2006) 3-D flow control for single-cell experiments: potentials and applications for plant science on a microchip. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol IV, Global Science Books, Ltd, UK, pp 137-151 Sartorato I, Zanin G, Baldoin C, Zanche CDE (2006) Observations on the potential of microwaves for weed control. Weed Research 46, 1-9 Shcherbakova I, Mitra S, Beer RH, Brenowitz M (2006) Fast Fenton footprinting: a laboratory-based method for the time-resolved analysis of DNA, RNA and proteins. Nucleic Acids Research 34, e48

Mitochondria/sporogenesis/sterility/fertility The induction of male-sterile phenotypes may be a key to the effective use of ornamentals without the fear/risk of spread of transgenic pollen into wild populations. Previously, transgenic Arabidopsis and tobacco plants were produced in which a wheat unedited ATP9 gene (u-ATP9) was fused to a gene fragment encoding a transit peptide of yeast COXIV. When u-ATP9 was expressed, a mitochondrial dysfunction characterized by lower rates of respiration was observed (Hernould et al. 1993, Gomez-Casati et al. 2002). When the CaMV35-S promoter is used top control the expression of u-ATP9 in Arabidopsis, changes in vegetative development are observed (Paul et al. 1992). However, when the same gene comes under the control of a flower-specific (specifically stamens and petals) promoter (viz. APETALA3 promoter; Jack et al. 1993) or a tapetum-specific promoter (A9 promoter) there are no changes in major phenotypic characters, but rather a dramatic effect on male reproductive organs (Gomez-Casati et al. 2002). Sporogenesis (= pollen development), which requires the proper functioning of the mitochondria, and which is a major energy-consuming event in plants, becomes disrupted when u-ATP9 is expressed. Busi et al. (2006) believe that nuclear-mitochondrion crosstalk exists, and that a mitochondrial dysfunction, as that caused by u-ATP9 expression, triggers a retrograde signal when an antisense u-ATP9 gene is used; this in turn induces some nuclear-encoded mitochondrial genes. These latest experiments in Arabidopsis hold promise for ornamental scientists who have interest in mitochondria-nucleus crossatlk, and in male-sterile induction. The effective production of commercial hybrid plants and for preventing the diffusion of seeds or pollen grains of genetically modified plants in the open field can be achieved by the production of male and female sterile plants. Mitsuda et al. (2006) used their Chimeric REpressor Gene-Silencing Technology (CRES-T) to four transcription factors, namely APETALA3, AGAMOUS, LEAFY and AtMYB26, involved in the regulation of petal and stamen identity, stamen and carpel identity, floral meristem identity and anther dehiscence, respectively, in Arabidopsis. Transgenic plants expressing each chimeric repressor exhibited, at high frequency, a sterile phenotype that resembled the loss-of-function phenotype of each corresponding gene. In addition, in rice, expression of the chimeric repressor derived from SUPERWOMAN1, the rice orthologue of APETALA3, resulted in the male sterile phenotype with high efficiency. Mori et al. (2006) identified a novel protein, designated GCS1 (GENERATIVE CELL SPECIFIC 1), using generative cells isolated from Lilium longiflorum pollen. Through immunological assays and pollen fusion experiments, authors concluded that GCS1 is a critical fertilization factor in angiosperms. Interestingly, and almost simultaneously, Nowak et al. (2006) characterized a mutation of the Arabidopsis thaliana Cdc2 homolog CDC2A (also called CDKA;1), which

has a paternal effect. In cdc2a mutant pollen, only one sperm cell, instead of two, is produced. Mutant pollen is viable but can fertilize only one cell in the embryo sac, allowing for a genetic dissection of the double fertilization process; furthermore the unfertilized endosperm developed. Fertilization in flowering plants initiates the development of the embryo and endosperm, which nurtures the embryo. A few genes subjected to imprinting are expressed in endosperm from their maternal allele, while their paternal allele remains silenced as is the case of the FWA gene which involves DNA methylation. Imprinting of the Polycomb group (Pc-G) gene MEDEA (MEA) was further elucidated by Jullien et al. (2006), who discovered that MEA imprinting is regulated by histone methylation mediated by several Pc-G activities during the entire plant life cycle; furthermore Pc-G complexes maintain MEA transcription silenced throughout vegetative life and male gametogenesis while in the endosperm, the maternal allele of MEA encodes an essential component of a Pc-G complex, which maintains silencing of the paternal MEA allele. Authors conclude that a feedback loop controls MEA imprinting. Höfig et al. (2006) used a male cone-specific promoter from Pinus radiata (radiata pine) to express a stilbene synthase gene (STS) in anthers of transgenic N. tabacum plants, resulting in complete male sterility in 70% of transformed plants. Their promoter­STS construct may be useful for the ablation of pollen formation in coniferous gymnosperms and male sterility may potentially be viewed as a minimum requirement for the commercial use of transgenic conifers. The bioenergetics of mitochondria, which may underlie some of the events in sporogenesis, have been reviewed by Logan (2006). Scott et al. (2006), also part of Logan's group, discuss the importance of the Arabidopsis BIGYIN gene in controlling the size and number of mitochodria. In independent studies, Gao et al. (2006) found that FZL is a new plant-specific member of the dynamin superfamily in Arabidopsis. FZL is a FZO-like protein, and FZO is a dynamin-related membrane-remodeling protein that mediates fusion between mitochondrial outer membranes in animals and fungi. Although fzl knockout mutants have abnormalities in chloroplast and thylakoid morphology, including disorganized grana stacks and alterations in the relative proportions of grana and stroma thylakoids, FZL levels do not affect mitochondrial morphology or ultrastructure, suggesting that mitochondrial morphology in plants is regulated by an FZO-independent mechanism. Smith and Anderson (2006) provide a stimulating discussion of male sterility in the prevention of weediness while Roitsch and Engelke (2006) provide a comprehensive and highly innovative perspective on cytoplasmic, genomic and transgene induced male sterility. Cytoplasmic male sterility or CMS is reviewed by Chae (2006).

Busi MV, Gómez-Casati DF, Perales M, Araya A, Zabaleta E (2006) Nuclear-encoded mitochondrial complex I gene expression is restored to normal levels by inhibition of unedited ATP9 transgene expression in Arabidopsis thaliana. Plant Physiology and Biochemistry 44, 1-6 Chase CD (2006) Genetically engineered cytoplasmic male sterility. Trends in Plant Science 11, 7-9 Gao H, Sage TL, Osteryoung KW (2006) FZL, an FZO-like protein in plants, is a determinant of thylakoid and chloroplast morphology. Proceedings of the National Academy of Sciences USA 103, 6759-6764 Gomez-Casati DF, Busi MV, Gonzalez-Schain N, Mouras A, Zabaleta EJ, Araya A (2002) A mitochondrial dysfunction induces the expression of nuclear-encoded complex I genes in engineered male sterile Arabidopsis thaliana. FEBS Letters 532, 70-74 Hernould M, Suharsono S, Litvak S, Araya A, Mouras A (1993) Male-sterility induction in transgenic tobacco plants with an unedited atp9 mitochondrial gene from wheat. Proceedings of the National Academy of

Sciences USA 90, 2370-2374 Höfig KP, Möller R, Donaldson L, Putterill J, Walter C (2006) Towards male sterility in Pinus radiata ­ a stilbene synthase approach to genetically engineer nuclear male sterility. Plant Biotechnology Journal 4, 333-343 Jack T, Brockman L, Meyerowitz EM (1992) The homeotic gene APETALA3 of Arabidopsis thaliana encodes a MADS box and is expressed in petals and stamens. Cell 68, 683-697 Jullien PE, Katz A, Oliva M, Ohad N, Berger F (2006) Polycomb group complexes self-regulate imprinting of the polycomb group gene MEDEA in Arabidopsis. Current Biology 16, 486-492 Logan DC (2006) The mitochondrial compartment. Journal of Experimental Botany 57, 1225-1243 Mitsuda N, Hiratsu K, Todaka D, Nakashima K, Yamaguchi-Shinozaki K, Ohme-Takagi M (2006) Efficient production of male and female sterile plants by expression of a chimeric repressor in Arabidopsis and rice. Plant Biotechnology Journal 4, 325-332 Mori T, Kuroiwa H, Higashiyama T, Kuroiwa T (2006) GENERATIVE CELL SPECIFIC 1 is essential for angiosperm fertilization. Nature Cell Biology 8, 64-71 Nowack MK, Grini PE, Jakoby MJ, Lafos M, Koncz C, Schnittger A (2006) A positive signal from the fertilization of the egg cell sets off endosperm proliferation in angiosperm embryogenesis. Nature Genetics 38, 63-67 Paul W, Hodge R, Smartt, S Draper J, Scott R (1992) The isolation and characterisation of the tapetum-specific Arabidopsis thaliana A9 gene. Plant Molecular Biology 19, 611-622 Roitsch T, Engelke T (2006) Cytoplasmic, genomic and transgene induced male sterility. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 512-522 Scott I, Tobin AK, Logan DC (2006) BIGYIN, an orthologue of human and yeast FIS1 genes functions in the control of mitochondrial size and number in Arabidopsis thaliana. Journal of Experimental Botany 57, 1275-1280 Smith AG, Anderson NO (2006) Engineered sterility for non-native plant invaders. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 232-239

Modelling and statistics Non-linear, mixed effects models were proposed to be one solution to predicting or describing the the (future) behaviour of a batch of biological products, as would be the case for ornamental cut flowers, or any postharvest product. Even though more methods of standardization are being implemented at the production stage, and even earlier (e.g. tissue-derived products) there had lacked, until now a definitive model that would take into account the heterogeneity in a batch of products (e.g. a bunch or bucket of roses at market). Classically the approaches used thus far assumed the change in behavior to be deterministic (fixed effects), with any biological variation included thereafter as a stochastic deviation of a single individual around the deterministic part (random effects). Some excellent models exist for determining the fixed effects (Tijskens et al. 2003), but for the random effects, which traditionally took a two-stage approach, can now be modelled in a single step, as demonstrated with the use of mixed effect models, taking into account both fixed and random effects (De Ketelaere et al. 2006).

De Ketelaere B, Stulens J, Lammertyn J, Cuong NV, De Baerdemaeker J (2006) A methodological approach for the identification and quantification of sources of biological variance in postharvest research. Postharvest Biology and Technology 39, 1-9 Tijskens LMM, Konopacki P, Simcic M (2003) Biological variance: burden or benefit. Postharvest Biology and Technology 27, 15-25

Molecular markers Aros et al. (2006) used RAPDs to discriminate nine wild alstroemeria accessions and 10 commercial varieties using and UPOVs morphological descriptors. More information about UPOVs and intellectual property rights may be found in Wegner's (2006) discussion. Amplified fragment length polymorphism (AFLP) markers were used by Chen et al. (2006) to detect genetic differences of

19 cultivars selected from somaclonal variants of Syngonium podophyllum, an ornamental plant. The inability to separate all cultivars was attributed to DNA methylation events or to rare mutations. Random amplified polymorphic DNA (RAPD) were used to establish the genetic relationships among seven Iris species (I. germanica, I. petrana, I. atrofusca, I. nigricans, I. vartanii, I. aucheri and I. edomensis), with two main clusters being separable (Al-Gabbiesh et al. 2006). Inter-specific crosses were carried out between two lines of Dianthus × isensis Hirahata et Kitam., and one line of D. japonicus Thunb. (Nimura et al. 2006). Hybrids were confirmed by RAPD analysis and flow cytometry, had intermediate characters of both parents with respect to leaf-width and flower-size, but flowered at the same time as each other with a uniform flower colour, purplish-pink. A general statistical mapping framework, called functional mapping, has been proposed to characterize, in a single step, the quantitative trait loci (QTLs) or nucleotides (QTNs) that underlie a complex dynamic trait. This important approach to describe the developmental mechanisms of trait formation and expression for each QTL or QTN has been reviewed by Wu and Lin (2006). Polymorphic sequence-tagged microsatellite sites (STMSs) were used by Scariot et al. (2006) to characterize 65 accessions of old garden roses, and cluster analysis grouped the genotypes into seven major clusters that were substantially consistent with their classification into botanical sections and horticultural groups. Schmid et al. (2006) characterized geographic patterns of genetic variation in A. thaliana by genotyping 115 genome-wide single nucleotide polymorphism (SNP) markers in 351 accessions from the whole species range using a matrix-assisted laser desorption/ionization time-of-flight assay, and by sequencing of nine unlinked short genomic regions in a subset of 64 accessions. Pot et al. (2006), conducting an experiment on maritime pine, dissected the genome to identify the regions involved in the variability of chemical and physical wood properties of Pinus pinaster, and detected 54 quantitative trait loci (QTLs), with an average of 2.4 QTLs per trait. Clusters of wood properties QTLs were found at several points in the genome, suggesting the existence of pleiotropic effects of a limited number of genes.

Al-Gabbiesh AH, Hassawi DS, Afifi FU (2006) Determination of genetic diversity among Iris species using random amplified polymorphic DNA analysis. Biotechnology 5, 173-179 Aros D, Meneses C, Infante R (2006) Genetic diversity of wild species and cultivated varieties of alstroemeria estimated through morphological descriptors and RAPD markers. Scientia Horticulturae 108, 86-90 Chen J, Henny RJ, Devanand PS, Chao CT (2006) AFLP analysis of nephthytis (Syngonium podophyllum Schott) selected from somaclonal variants. Plant Cell Reports 24, 743-749 Nimura M, Kato J, MII M, Katoh T (2006) Amphidiploids produced by natural chromosome-doubling in inter-specific hybrids between Dianthus × isensis Hirahata et Kitam. and D. japonicus Thunb. The Journal of Horticultural Science and Biotechnology 81, 72-77 Pot D, Rodrigues JC, Rozenberg P, Chantre G, Tibbits J, Cahalan C, Pichavant F, Plomion C (2006) QTLs and candidate genes for wood properties in maritime pine (Pinus pinaster Ait.). Tree Genetics and Genomes 2, 10-24 Schmid KJ, Törjék O, Meyer R, Schmuths H, Hoffmann MH, Altmann T (2006) Evidence for a large-scale population structure of Arabidopsis thaliana from genome-wide single nucleotide polymorphism markers. Theoretical and Applied Genetics 112, 1104-1114 Scariot V, Akkak A, Botta R (2006) Characterization and genetic relationships of wild species and old garden roses based on microsatellite

analysis. Journal of the American Society for Horticultural Science 131, 66-73 Wegner J (2006) Intellectual property on plant varieties. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 240-243 Wu R, Lin M (2006) Functional mapping - how to map and study the genetic architecture of dynamic complex traits. Nature Reviews Genetics 7, 229-237

Mutagenesis Kumar et al. (2006) used RAPD markers to differentiate radiomutants. The benefits, limits and potentials of radiation mutagenesis have been extensively and comprehensively covered in Volume I of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. van der Ploeg and Heuveling (2006) review the effects of temperature, especially in the sub-optimal temperature range, on growth and development of chrysanthemum (Dendranthema grandiflorum syn. Chrysanthemum morifolium) in a greenhouse context. Muller's ratchet is a hypothesis that claims that asexual reproduction is detrimental, mainly because of the accumulation of deleterious mutations over time. In Angiosperms, most asexually reproducing genetic systems are polyploid, with apomictic species (plants forming seeds without fertilization) as well as plastids and mitochondria providing prominent examples of possible evasive mechanisms to Muller's ratchet. Khakhlova and Bock (2006) describe a system using transgenic tobacco chloroplasts in which gene conversion acts as a highly efficient mechanism by which the polyploid plastid genetic system can correct deleterious mutations and make one good genome out of two bad ones.

Khakhlova O, Bock R (2006) Elimination of deleterious mutations in plastid genomes by gene conversion. The Plant Journal 46, 85-94 Kumar S, Prasad KV, Choudhary ML (2006) Detection of genetic variability among chrysanthemum radiomutants using RAPD markers. Current Science 90, 1108-1112 van der Ploeg A, Heuveling E (2006) The influence of temperature on growth and development of chrysanthemum cultivars: a review. The Journal of Horticultural Science and Biotechnology 81, 174-182

Mycorrhiza and nodulation Plants, when under flooded conditions, may not always be able to supply sufficient oxygen to continue aerobic respiration; nitrogen uptake and utilizatrion may also subsequently be affected. The presence of arbuscular mycorrhizal (AM) associations tends to improve plant tolerance to water stress. These themes, as well as the fact that Aster tripolium forms natural AM associations under flood conditions in salt marsh environments suggests this plant to be an interesting model plant for studying both AM-plant associations as well as salt stress physiology (Neto et al. 2006). Established A. tropolium plants having the AM association having a better tolerance to flooding was mediated through an improvement of the osmotic adjustment of the plant tissues (higher concentrations of soluble sugars and proline) and through the increment of nitrogen acquisition in tidal-flooded plants. How plants have adapted to flooded conditions, and the molecular regulatory networks involved in these responses, including the putative signals to sense submergence, are reviewed by Voesenek et al. (2006). From the same laboratory, studies on ectomycorrhizal establishment of Pisolithus tinctorius on Pinus pinaster plants showed that this symbiotic relationship was in fact detrimental rather than beneficial to pine plants, but that this physiologically negative status depended on the age of the plant (i.e. a greater stress was generally observed in younger plants; Corrêa et al.

2006). A model to explain the role of auxin during autoregulation of nodulation of indeterminate legumes was proposed by van Noorden et al. (2006) in which they propose that: 1) high levels of endogenous auxin are correlated with increased numbers of nodules, 2) inoculation of roots reduces auxin loading from the shoot to the root, and 3) subsequent reduction of auxin levels in the root inhibits further nodule initiation. These assumptions were made after extensive studies with the Medicago truncatula supernodulating mutant sunn (super numeric nodules). Mergaert et al. (2006), using recombinant Rhizobium strains nodulating both legume types, i.e. galegoid and nongalegoid, show that bacteroid differentiation is controlled by the host plant and that plant factors present in nodules of galegoid legumes but absent from nodules of nongalegoid legumes block bacterial cell division and trigger endoreduplication cycles, thereby forcing the endosymbionts toward a terminally differentiated state, in other words the evolution of a mechanism to dominate the symbiosis. Endoreduplication, the successive duplication of chromosomal DNA in the absence of mitosis, is common ion plant cells: it may be regulated at its entry by mitotic cyclin-dependent kinase activity, while an A. thaliana cyclin A gene, CYCA2;3 negatively regulates endocycles and acts as a key regulator of ploidy levels in Arabidopsis endoreduplication (Imai et al. 2006). Danesh et al. (2006) used carrot hairy root cultures to optimize conditions for the production of AM Fungi. In a fascinating result, Li et al. (2006) show how AM fungus induces a defense response against the root-knot nematode, Meloidogyne incognita in mycorrhizal grapevine roots, apparently involving transcriptional control of VCH3 (a class III chitinase gene) expression throughout the whole root tissue. A plant nucleoporin gene, Nup133, is essential for a symbiotic signal transduction pathway shared by Rhizobium bacteria and mycorrhizal fungi. This genetics of this mechanism was analysed by Kanamori et al. (2006). In order to identify and assess the frequency and tissue specificity of plant genes in the actinorhizal Casuarina glauca­Frankia symbiosis expressed sequence tag (EST) analysis was performed (Hocher et al. 2006). Nara (2006) summarizes ECMs and CMNs. Ectomycorrhizal (ECM) fungal mycelia are the main organs for nutrient uptake in many woody plants, and often connect seedlings to mature trees, and resources are shared among connected plants via common mycorrhizal networks (CMNs). He showed that the positive effects of CMNs on seedling performance were significantly different among ECM fungal species. Six chemically induced spontaneously nodulating mutants in model legume Lotus japonicus were isolated under axenic conditions, i.e., in the absence of rhizobia (Tirichine et al. 2006). Transgenic Arabidopsis plants carrying the chimeric MtPAP1 gene from Medicago truncatula, which codes for a purple acid phosphatase, showed 4.6- to 9.9-fold higher acid phosphatase activities in the root apoplast relative to the control plants, and when 2 mM phytate was supplied as the sole source of phosphorus all the tested transgenic lines showed an at least two-fold increase in biomass production and total phosphorus content (Xiao et al. 2006). Transgenic ornamentals whose

growth I sinhibuited by poor phosphate uptake may be benefitted by overexpression of the M. truncatula acid phosphatase gene. den Herder et al. (2006) provide one of the most comprehensive and up-to-date reviews available on nodulation, focusing primarily on the latest molecular achievements.

Corrêa A, Strasser RJ, Martins-Loução MA (2006) Are mycorrhiza always beneficial? Plant and Soil 279, 65-73 Danesh YR, Goltapeh EM, Alizadeh A, Sanavy MM (2006) Optimizing carrot hairy root production for monoxenic culture of arbuscular mycorrhizal fungi in Iran. Journal of Biological Sciences 6, 87-91 den Herder G, Holsters M, Goormachtig S (2006) Advances in legume nodulation. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol III, Global Science Books, Ltd, UK, pp 431-446 Hocher V, Auguy F, Argout X, Laplaze L, Franche C, Bogusz D (2006) Expressed sequence-tag analysis in Casuarina glauca actinorhizal nodule and root. New Phytologist 169, 681-688 Imai KK, Ohashi Y, Tsuge T, Yoshizumi T, Matsui M, Oka A, Aoyama T (2006) The A-type cyclin CYCA2;3 is a key regulator of ploidy levels in Arabidopsis endoreduplication. The Plant Cell 18, 382-396 Kanamori N, Madsen LH, Radutoiu S, Frantescu M, Quistgaard EMH, Miwa H, Downie JA, James EK, Felle HH, Haaning LL, Jensen TH, Sato S, Nakamura Y, Tabata S, Sandal N, Stougaard J (2006) A nucleoporin is required for induction of Ca2+ spiking in legume nodule development and essential for rhizobial and fungal symbiosis. Proceedings of the National Academy of Sciences USA 103, 359-364 Li H-Y, Yang G-D, Shu H-R, Yang Y-T, Ye B-X, Nishida I, Zheng C-C (2006) Colonization by the arbuscular mycorrhizal fungus Glomus versiforme induces a defense response against the root-knot nematode Meloidogyne incognita in the grapevine (Vitis amurensis Rupr.), which includes transcriptional activation of the class III chitinase gene VCH3. Plant and Cell Physiology 47, 154-163 Mergaert P, Uchiumi T, Alunni B, Evanno G, Cheron A, Catrice O, Mausset AE, Barloy-Hubler F, Galibert F, Kondorosi A, Kondorosi E (2006) Eukaryotic control on bacterial cell cycle and differentiation in the Rhizobium­legume symbiosis. Proceedings of the National Academy of Sciences USA 103, 5230-5235 Nara K (2006) Ectomycorrhizal networks and seedling establishment during early primary succession. New Phytologist 169, 169-178 Neto D, Carvalho LM, Cruz C, Martins-Loução MA (2006) How do mycorrhizas affect C and N relationships in flooded Aster tripolium plants? Plant and Soil 279, 51-63 Tirichine L, James EK, Sandal N, Stougaard J (2006) Spontaneous root-nodule formation in the model legume Lotus japonicus: a novel class of mutants nodulates in the absence of rhizobia. Molecular Plant-Microbe Interactions 19, 373-382 van Noorden GE, Ross JJ, Reid JB, Rolfe BG, Mathesius U (2006) Defective long-distance auxin transport regulation in the Medicago truncatula super numeric nodules mutant. Plant Physiology 140, 1494-1506 Voesenek LACJ, Colmer TD, Pierik R, Millenaar FF, Peeters AJM (2006) How plants cope with complete submergence. New Phytologist 170, 213-226 Xiao K, Katagi H, Harrison M, Wang Z-Y (2006) Improved phosphorus acquisition and biomass production in Arabidopsis by transgenic expression of a purple acid phosphatase gene from M. truncatula. Plant Science 170, 191-202

Nicotiana Tobacco continues to be one of the most important model plants, serving as a reference for physiological, biochemical and gentic studies. In the light of this, great attention was paid to finding ideal, effective and repetitive genetic transformation systems based on four transformation techniques (Teixeira da Silva 2005). An important step in the production of nicotine is the methylation of putrescine by putrescine N-methyl transferase or PMT. PMT transfers a methyl group from S-adenosylmethionine (SAM) to putrescine, producing N-methylputrescine and S-adenosylhomocysteine (SAH) as products, and decreasing PMT mRNA levels by co-suppression, antisense, or RNAi approaches reduces nicotine accumulation levels (Chintapakorn and Hamill 2003, Steppuhn et al. 2004). Since nicotine is produced in the roots, and transported to the leaves where it serves as an insecticide, understanding the expression mechanisms of genes and enzymes involved in nicotine

formation (Heim et al. 2006) may provide some valuable alternative solutions to transgenic pest-control strategies for ornamentals. In a two-step experiment aimed at determining the effect of virus-induced gene silencing (VIGS) on genes associated with ethylene signaling, Shan and Goodwin (2006) showed how introduction of NbACO1, an 1-aminocyclopropane- 1-carboxylic acid (ACC) oxidase derived from Nicotiana benthamiana leaves infected with the hemibiotrophic fungal pathogen, Colletotrichum orbiculare into a PVX vector for virus-induced gene silencing resulted in a reduction in its expression to 7-9% of that found in the controls for fungal-infected leaf tissue. DNA methylation characterizes many silencing evnts. Pröll et al. (2006) established a high-sensitive assay for the determination of methylation levels in genomic regulatory DNA sequences by detecting 5'methyl-cytosines (5'mC) in non-bisulfite-treated DNA. Pazhouhandeh et al. (2006) propose a model to explain how plant viruses encode proteins that can suppress RNA silencing since plants employ small RNA-mediated posttranscriptional gene silencing as a virus defense mechanism while Xie and Guo review VIGS in antiviral silencing in plants. VIGS offers a rapid and high-throughput technique platform for gene function analysis. The parameters potentially affecting the efficiency of VIGS in Arabidopsis were investigated: the concentration and pre-incubation of Agrobacterium inocula (agro-inocula), the concentration of acetosyringone included in agro-inocula, the Agrobacterium inoculation (agro-inoculation) method, the ecotypes and the growth stages of Arabidopsis plants for agro-inoculation, and the growth temperature of agro-inoculated plants (Wang et al. 2006). Authors concluded that the best conditions were: agro-inocula with OD600 of 2.0, pre-incubating for 2 h in infiltration buffer containing 200 m acetosyringone, agro-inoculating by vacuum infiltration, and growth of agro-inoculated plants at 22 -24°C. Tobacco chloroplasts were transformed by biolistics with a tobacco chloroplast expression vector, pTRVP1, containing the foot-and-mouth disease virus (FMDV) VP1 gene and the selective marker aadA gene (Li et al. 2006). Plant chloroplasts were shown, through this study, to be an efficient expression system for the potential production of recombinant antigens in plants. FMDV is the etiological agent of an important disease of livestock, and the capacity to generate an edible vaccine for cattle or livestock provides great avenue for exploration of ornamental and forage crop transgenics. Kathleen Hefferon (2006) further examines the possibilities of viral-expression vectors for plants. Related studies by Praveen et al. (2006) show how the CMV-cp and ToLCV-cons-rep genes from the isolates of cucumber mosaic virus (CMV) and tomato leaf curl virus (ToLCV), respectively, were transcriptionally fused under the control of CaMV 35 S promotor, and transformed, using Agrobacterium, into tobacco and tomato. Transgenic plants housing this homologous chimeric gene construct produced RNAs, were capable of duplex formation, and conferred gene silencing, making this an intyeresting model protocol to study virus-induced gene silencing mechanisms. For some excellent reviews of RNAi-mediated transgene silencing and PTGS, readers are referred to Volume III of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. In addition Krichevsky et al. (2006) review the molecular mechanisms by which plant viruses find their way into and out

of the host cell nucleus. Two ipt transgenic N. tabacum cultivars were analysed for several physiological parameters, and selected according to intensity of the introduced gene expression and the resulting amount of synthesised cytokinins (CK). CK content increased 379% in in vitro plants, but no increase was registered in seed-derived transgenics (Kveton 2006). An increase in the CK amounts in the transformants led to a subsequent decrease in leaf area, fresh and dry masses, and chlorophyll and soluble protein contents, suggesting a stress factor for the plant. Almost in support of these results, and complimentary to the findings of Kveton, Synkova et al. (2006) show how transgenic tobacco with the ipt gene under the control of the promoter of small subunit of Rubisco (Pssu-ipt), when grown either as grafts on control rootstocks or as rooted plants, resulted in large increases in the amounts of CKs (predominantly zeatin and zeatin riboside), and select antioxidant activities (ascorbate, syringaldazine and guaiacol peroxidase). CK biosynthesis and perception of CK signals in Arabidopsis are reviewed by Hwang and Sakakibara (2006). The cytokinin signal is perceived by histidine kinase receptors leading to delayed leaf senescence, and Kim et al. (2006) found that AHK3, one of the three cytokinin receptors in Arabidopsis, plays a major role in controlling cytokinin-mediated leaf longevity through a specific phosphorylation of a response regulator, ARR2. Transgenic tobacco plants harbouring mrip1, a Vitis-derived fruit- and ripening-specific proline-rich protein gene, and fused to gfp, showed tissue- and developmental-specific regulation of GFP expression in the flowers (Burger et al. 2006). Analysis of the 2.8 kb directly upstream of the mrip1 TIS (transcription initiation site) revealed several putative cis-acting regulatory elements, including a spectrum of hormone-, light-, phytochrome-, sugar- and stress-responsive elements. Ning et al. (2006) showed how, in Nicotiana, the transcriptome is restructed in zygote and that the maternal-to-zygotic transition happens before the first zygotic division, which is much earlier in higher plants than in animals. In this study authors used subtractive hybridization and mirror orientation selection to compare gene expression profiles of isolated Nicotiana tabacum cv SR1 zygotes and egg cells. The mRNA levels of various cell cycle-related genes, including MAP kinase genes and cyclin genes, in cultured tobacco cells (Nicotiana tabacum cv. Xanthi, line XD6S) decreased in response to the presence of fungal elicitors, a xylanase from Trichoderma viride and an extract from the cell wall of Phytophthora infestans (Suzuki et al. 2006). Authors believe that there may be a negative cross-talk between signal transduction pathways for growth and defence responses, which might be important for adaptation to environmental stress by potential pathogens. Glenz et al. (2006) showed how functionally active bacterial lipoproteins can be processed in plants after engineering transplastomic tobacco plants that accumulate the outer surface lipoprotein A (OspA) - the basic constituent of the first generation monovalent human vaccine against Lyme disease. Using N. tabacum and N. sylvestris, Tillich et al. (2006) discuss the importance of RNA editing in plant organelles, which is mediated by site-specific, nuclear-encoded factors, and whose editing activities are conserved despite the absence of their target sites, potentially because they serve other functions

in the plant cell. Coleman et al. (2006) demonstrated how the up-regulation of the sucrose synthase (SuSy) and UDP-glucose pyrophosphorylase (UGPase) genes, although not increasing the percentage cellulose content, was effective in increasing the total N. tabacum cv. Xanthi biomass, and thus the overall cellulose yield, from a given plant. Gardner et al. (2006) studied the differential expression of rolC in N. tabacum `Samsun' plants using either the 35S promoter, the light-inducible rbcS promoter, or the native rolC promoter. Depending on the cultivar and promoter, authors found that expression of the rolC gene caused pleiotropic effects, affecting gene expression and phenotype related to plant height, leaf color, root growth, leaf size, corolla length, and stem diameter. The use of rolC genes in ornamental horticulture has been reviewed by Smith et al. (2006). Incidentally the Brassica napus Brrga1-d dwarf gene served as an excellent marker gene with visibly reduced height in transgenic plants (Muangprom et al. 2006); in addition it also is a `perfect' PCR marker for selection of the Brrga1-d gene that is based on detecting the nucleotide mutation causing the dwarf phenotype. Grafting was shown to improve nitrogen use efficiency (specifically improved NO3- assimilation) in tobacco (Ruiz et al. 2006), with subsequent beneficial implications for human health and for a reduction in environmental pollution. The nectar of ornamental tobacco is extremely rich (2 mM) in proline. Since insects such as honeybees prefer proline-rich nectars, Carter et al. (2006) hypothesize that some plants offer proline-rich nectars as a mechanism to attract visiting pollinators. N. tabacum plants transformed with an antisense suppressor of the gene for proline dehydrogenase showed increased salt tolerance (Kolodyazhnaya et al. 2006). Seven fragments derived from AFLP analysis were associated with three different resistances: two for the blue-mold (Peronospora tabacina Adam) resistance derived from Nicotiana debneyi Domin, two for the Va gene (Potato Virus Y susceptibility), and three for the black root rot (Chalara elegans) resistance of N. debneyi origin (Julio et al. 2006). Some of these were converted into SCAR (sequence characterized amplified region) markers and validated on recombinant inbred lines or doubled-haploid lines.

Burger AL, Watts L, Botha FC (2006) Grapevine promoter directs gene expression in the nectaries of transgenic tobacco. Physiologia Plantarum 126, 418-434 Carter C, Shafir S, Yehonatan L, Palmer RG, Thornburg R (2006) A novel role for proline in plant floral nectars. Naturwissenschaften 93, 72-79 Chintapakorn Y, Hamill JD (2003) Antisense-mediated down-regulation of putrescine N-methyltransferase activity in transgenic Nicotiana tabacum L. can lead to elevated levels of anatabine at the expense of nicotine. Plant Molecular Biology 53, 87-105 Coleman HD, Ellis DD, Gilbert M, Mansfield SD (2006) Up-regulation of sucrose synthase and UDP-glucose pyrophosphorylase impacts plant growth and metabolism. Plant Biotechnology Journal 4, 87-101 Gardner N, Melberg T, George M, Smith AG (2006) Differential expression of rolC results in unique plant phenotypes. Journal of the American Society for Horticultural Science 131, 82-88 Glenz K, Bouchon B, Stehle T, Wallich R, Simon MM, Warzecha H (2006) Production of a recombinant bacterial lipoprotein in higher plant chloroplasts. Nature Biotechnology 24, 76-77 Hefferon KL (2006) Novel approaches to protein expression using plant virus expression vectors. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 30-40 Heim WG, Lu R-H, Jelesko JG (2006) Expression of the SAM recycling pathway in Nicotiana tabacum roots. Plant Science 170, 835-844 Hwang I, Sakakibara H (2006) Cytokinin biosynthesis and perception.

Physiologia Plantarum 126, 528-538 Julio E, Verrier JL, de Borne FD (2006) Development of SCAR markers linked to three disease resistances based on AFLP within Nicotiana tabacum L. Theoretical and Applied Genetics 112, 335-346 Kim HJ, Ryu H, Hong S-H, Woo H-R, Lim P-O, Lee I-C, Sheen J, Nam HG, Hwang I (2006) Cytokinin-mediated control of leaf longevity by AHK3 through phosphorylation of ARR2 in Arabidopsis. Proceedings of the National Academy of Sciences USA 103, 814-819 Kolodyazhnaya YS, Titov SE, Kochetov AV, Komarova ML, Romanova AV, Koval' VS, Shumny VK (2006) Evaluation of salt tolerance in Nicotiana tabacum plants bearing an antisense suppressor of the proline dehydrogenase gene. Russian Journal of Genetics 42, 212-214 Krichevsky A, Kozlovsky SV, Gafni Y, Citovsky V (2006) Nuclear import and export of plant virus proteins and genomes. Molecular Plant Pathology 7, 131-146 Kveton J (2006) Extent of ipt gene expression and resulting amount of cytokinins affect activities of carboxylation enzymes in transgenic plants. Biologia Plantarum 50, 21-30 Li Y, Sun M, Liu J, Yang Z, Zhang Z, Shen G (2006) High expression of foot-and-mouth disease virus structural protein VP1 in tobacco chloroplasts. Plant Cell Reports 25, 329-333 Muangprom A, Mauriera I, Osborn TC (2006) Transfer of a dwarf gene from Brassica rapa to oilseed B. napus, effects on agronomic traits, and development of a `perfect' marker for selection. Molecular Breeding 17, 101-110 Ning J, Peng X-B, Qu L-H, Xin H-P, Yan T-T, Sun M (2006) Differential gene expression in egg cells and zygotes suggests that the transcriptome is restructed before the first zygotic division in tobacco. FEBS Letters 580, 1747-1752 Pazhouhandeh M, Dieterle M, Marrocco K, Lechner E, Berry B, Brault V, Hemmer O, Kretsch T, Richards KE, Genschik P, Ziegler-Graff V (2006) F-box-like domain in the polerovirus protein P0 is required for silencing suppressor function. Proceedings of the National Academy of Sciences USA 103, 1994-1999 Praveen S, Mishra AK, Antony G (2006) Viral suppression in transgenic plants expressing chimeric transgene from Tomato Leaf Curl Virus and Cucumber Mosaic Virus. Plant Cell, Tissue and Organ Culture 84, 49-55 Pröll J, Födermayr M, Wechselberger C, Pammer P, Sonnleitner M, Zach O, Lutz D (2006Ultrasensitive immunodetection of 5'Methyl cytosine for DNA methylation analysis on oligonucleotide microarrays. DNA Research 13, 37-42 Ruiz JM, Rivero RM, Cervilla LM, Castellano R, Romero L (2006) Grafting to improve nitrogen-use efficiency traits in tobacco plants. Journal of the Science of Food and Agriculture 86, 1014-1021 Shan XC, Goodwin PH (2006) Silencing an ACC oxidase gene affects the susceptible host response of Nicotiana benthamiana to infection by Colletotrichum orbiculare. Plant Cell Reports 25, 241-247 Smith AG, John KE, Gardner N (2006) Dwarfing ornamental crops with the rolC gene. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 54-59 Steppuhn A, Gase K, Krock B, Halitschke R, Baldwin IT (2004) Nicotine's defensive function in nature. PLoS Biology 2, E217 Suzuki K, Nishiuchi T, Nakayama Y, Ito M, Shinshi H (2006) Elicitor-induced down-regulation of cell cycle-related genes in tobacco cells. Plant, Cell and Environment 29, 183-191 Synkova H, Semoradova S, Schnablova R, Witters E, Husak M, Valcke R (2006) Cytokinin-induced activity of antioxidant enzymes in transgenic Pssu-ipt tobacco during plant ontogeny. Biologia Plantarum 50, 31-41 Teixeira da Silva JA (2005) Simple multiplication and effective genetic transformation (4 methods) of in vitro-grown tobacco by stem thin cell layers. Plant Science 169, 1046-1058 Tillich M, Poltnigg P, Kushnir S, Schmitz-Linneweber C (2006) Maintenance of plastid RNA editing activities independently of their target sites. EMBO Reports 7, 308-313 Wang C, Cai X, Wang X, Zheng Z (2006) Optimisation of tobacco rattle virus-induced gene silencing in Arabidopsis. Functional Plant Biology 33, 347-355 Xie Q, Guo H-S (2006) Systemic antiviral silencing in plants. Virus Research 118, 1-6

Orchids Ascocentrum ampullaceum var. auranticum and Vanda coerulea, an endangered orchid of Appendix I of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) were hybridized to form a primary hybrid genus with intermediate and improved characters in the F1 generation (Kishor et al. 2006). Hybrid seed could be successfully germinated on half-strength MS medium supplemented with 2.3 M Kin + 0.5 M NAA. RAPD analyses based on morphological, physiological and ecological characteristics were used to elucidate the classification of oriental cymbidiums, including 21 cymbidiums, 15 species including three Cymbidium gyokuchin, 4 Cymbidium

kanran and 2 Cymbidium goeringii cultivars (Choi et al. 2006). Martin and Madassery (2006) were able to generate protocorm-like bodies (PLBs) from foliar explants in Dendrobium hybrids Sonia 17 and 28, important commercial cultivars. A two-step process was required: first, these leaf explants were derived from flower stalk node derived shoots and cultured on half-strength MS medium supplemented with 44.4 M BA resulting in the formation of shoots; second step involved the culture of leaves from these in vitro derived shoots on the same medium, resulting in PLB formation. Re-conversion of PLBs back into shoots was enhanced by the addition of 6.97 M Kin on half-strength MS medium while 2 g/l activated charcoal was useful for rooting. An efficient micropropogation method for Cypripedium flavum (rare lady's slipper orchid), a Chinese endemic with a yellow flower, having conservation and commercial needs, was established by Yan et al. (2006). They germinated seeds on Harvais medium supplemented with BAP (2.22 M) and 2% (w/v) potato homogenate. Activated charcoal in half-strength Harvais improved rooting. Cymbidium continues to be a difficult to propagate in vitro, but once a good methodology has been achieved, the process becomes absolutely easy. Teixeira da Silva et al. (2006) produced protocols following the extensive examination of biotic factors (namely various explant sources: PLB, leaf tip or base, root tip or base, cell and tissue `suspension') in order to induce vigorously-rooting plantlets from PLBs within 3 months. The model plant, epiphytic hybrid Cymbidium Twilight Moon `Day Light', was shwon to induce most PLBs and callus induction when whole PLBs, PLB segments or PLB transverse thin cell layers (tTCLs) or longitudinal TCLs (lTCLs) were used. Plantlet growth and performance were analysed and copared using measurements of chlorophyll content, flow cytometric analyses and mtDNA analyses for variability. A 100% survival rate of in vitro-acclimatized plantlets was shown. Su et al. (2006) showed differential somatic embryogenic responses of Oncidium cv. Sweet Sugar leaf explants to several phytohormones, the best response occurring at 20 g/dm3 sucrose, 85 mg/dm3 NaH2PO4 and 3 mg/dm3 kinetin. A new term "multi-state form" was coined to describe the fusion of somatic embryos at the base. Genomic DNA polymorphisms of four Dendrobium species were profiled using suppression subtraction hybridization, or SSH (Li et al. 2006). Candidate genes for A, B, C, D and E function from Dendrobium crumenatum were isolated in order to investigate the regulatory mechanisms underlying orchid flower development, including AP2-, PI/GLO-, AP3/DEF-, AG- and SEP-like genes, respectively (Xu et al. 2006). Janna et al. (2006) optimized conditions for the biolistic delivery and expression of uidA gene in Dendrobium Sonia. A novel chalcone synthase gene was isolated from Phalaenopsis hybrida orchid flowers (Han et al. 2006). Readers may find a section dedicated to advances in orchid biotechnology in Volume IV of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues.

Choi SH, Kim M-J, Lee J-S, Ryu K-H (2006) Genetic diversity and phylogenetic relationships among and within species of oriental cymbidiums based on RAPD analysis. Scientia Horticulturae 108, 79-85 Han YY, Ming F, Wang J-W, Wen J-G, Ye M-M, Shen D-L (2006) Cloning and characterization of a novel chalcone synthase gene from Phalaenopsis

hybrida orchid flowers. Russian Journal of Plant Physiology 53, 223-230 Janna OA, Maziah M, Ahmad Parveez GKA, Saleh K (2006) Factors affecting delivery and transient expression of -glucuronidase gene in Dendrobium Sonia protocorm-like-body. African Journal of Botechnology 5, 88-94 Kishor R, Sha Valli Khan PS, Sharma GJ (2006) Hybridization and in vitro culture of an orchid hybrid Ascocenda `Kangla'. Scientia Horticulturae 108, 66-73 Li T-X, Wang J-K, Bai Y-F, Lu Z-H (2006) Diversity suppression-subtractive hybridization array for profiling genomic DNA polymorphisms. Journal of Integrative Plant Biology 48, 460-467 Martin KP, Joseph M (2006) Rapid in vitro propagation of Dendrobium hybrids through direct shoot formation from foliar explants, and protocorm-like bodies. Scientia Horticulturae 108, 95-99 Su Y-J, Chen J-T, Chang W-C (2006) Efficient and repetitive production of leaf-derived somatic embryos of Oncidium. Biologia Plantarum 50, 107-110 Teixeira da Silva JA, Singh N, Tanaka M (2006) Priming biotic factors for optimal protocorm-like body and callus induction in hybrid Cymbidium (Orchidaceae), and assessment of cytogenetic stability in regenerated plantlets. Plant Cell, Tissue and Organ Culture 84, 119-128 Xu Y, Teo LL, Zhou J, Kumar PP, Hao Yu (2006) Floral organ identity genes in the orchid Dendrobium crumenatum. The Plant Journal 46, 54-68 Yan N, Hu H, Huang J-l, Xu K, Wang H, Zhou Z-K (2006) Micropropagation of Cypripedium flavum through multiple shoots of seedlings derived from mature seeds. Plant Cell, Tissue and Organ Culture 84, 114-118

Other results, and other model systems In a January article of Nature, Keppler et al. (2006) found that living plants, as well as plant litter, emit methane to the atmosphere under oxic conditions. This additional source of methane could account for 10-30% of the annual methane source strength. Previously, it was thought that methane formed naturally only in anaerobic conditions, in marshes for instance. Tretment of French marigold (Tagetes patula L. `Boy Orange') with PEG-8000 at 15-30 g/l reduced elongation of marigold seedlings without negatively affecting germination, survival, or plant quality (Burnett et al. 2006). Sensors (on-line monitoring) and control systems are important tools for fine-tuning the supply of water and nutrients to the plants' demand for optimal control of production and reduction of system losses. Using infrared (IR) thermometry, Blom-Zandstra and Metselaar (2006) assessed the critical soil moisture status for optimal growth of Chrysanthemum plants. Reduction of seedling height could be achieved in Verbena (Verbena ×hybrida Voss. `Quartz White'), pansy (Viola wittrockiana L. `Bingo Yellow Blotch'), and celosia (Celosia cristata L. `New Look') after seeds were treated with paclobutrazol, but efficiency was species-, concentration and soaking-time-dependent (Magnitskiy et al. 2006). Shoot apical growth usually inhibits outgrowth of axillary buds, but after decapitation of the shoot apex, outgrowth of axillary buds begins. To elucidate the biochemical basis of such a reaction, Tanaka et al. (2006) demonstrated that in apical dominance one role of auxin is to repress local biosynthesis of cyotkinin in the nodal stem and that, after decapitation, cyotkinins, possibly derived from the roots, are locally biosynthesized in the nodal stem rather than in the roots. Parasitic plant development, including germination, haustorium induction, invasion, and haustorial structures and functions, have been reviewed by Shen.

Blom-Zandstra M, Metselaar K (2006) Infrared thermometry for early detection of drought stress in Chrysanthemum. HortScience 41, 136-142 Burnett SE, van Iersel MW, Thomas PA (2006) Medium-incorporated PEG-8000 reduces elongation, growth, and whole-canopy carbon dioxide exchange of marigold. HortScience 41, 124-130 Keppler F, Hamilton JTG, Braß M, Röckmann T (2006) Natural natural gas plants. Nature 439, 187-191 Magnitskiy SV, Pasian CC, Bennett MA, Metzger JD (2006) Controlling plug height of Verbena, Celosia, and Pansy by treating seeds with paclobutrazol. HortScience 41, 158-161

Shen H, Ye W, Hong L, Huang H, Wang Z, Deng X, Yang Q, Xu Z (2006) Progress in Parasitic Plant Biology: Host Selection and Nutrient Transfer. Plant Biology (Stuttg) 8, 175-185 Tanaka M, Takei K, Kojima M, Sakakibara H, Mori H (2006) Auxin controls local cytokinin biosynthesis in the nodal stem in apical dominance. The Plant Journal 45, 1028-1036

Pathogenesis and pathogen/pest-resistance Gentisic acid or 2,5-dihydroxybenzoic acid, a metabolic derivative of salicylic acid (SA) accumulated in the plant-pathogen systems, Cucumis sativus and Gynura aurantiaca when infected with either prunus necrotic ringspot virus (PNRSV) or the exocortis viroid (CEVd), and may act as an additional signal to SA for the activation of plant defenses, producing a nonnecrotic reaction (Bellés et al. 2006). Reverse peptide of indolicidin (Rev4) possesses both strong antimicrobial and protease inhibitory activities in vitro. This property was explored by Xing et al. (2006) to produce transgenic tobacco and Arabidopsis expressing Rev4 with different signal peptide sequences for pathogen resistance. Even though the transgenic plants exhibited elevated resistance to three bacterial and two oomycete pathogens, all transgenic plants showed normal growth and development, an indication of no or low cytotoxicity of the peptide. Of further surprise was a 34% increase in biomass production, shown by field trials. Novel antimicrobials based on "silicon alcohols" or silanols, as well as t-butanol, and siloxanes proved to be effective in antimicrobial tests carried out against Gram-negative bacteria, Escherichia coli, and Gram-positive, Staphylococcus aureus (KIm et al. 2006). The application as an insecticidal or as a herbicide has not yet been tested. The advantage seems to be that these novel biocide silanols can be prepared from low cost intermediates derived from the commercial processes associated with the silicone industry; moreover they are considered to be environmentally benign because of their transitory nature and ultimate conversion to CO2, SiO2, and H2O. In order to reduce the use of herbicide in crop production ( competitive cropping systems), Blackshaw et al. (2006) list the following factors as being important: diverse crop rotations, competitive cultivars, higher crop seed rates, reduced row spacing, specific fertilizer placement, and cover crops. Gene-specific transcript profiling of six DIR-a genes confirmed rapid and strong accumulation (up to 500-fold) in wound- and weevil-induced stem bark and xylem, suggesting a role for spruce DIR (dirigent protein) genes in constitutive and induced phenolic defense mechanisms against stem-boring insects. In this study Ralph et al. (2006) show how the importance of DIR genes in defense mechanisms in Sitka spruce (Picea sitchensis), but parallele mechanisms may be in play in other woody plants, inlcuding woody ornamentals, many of which consist of a mechanical defense barrier made up of outer stem tissues consisting of suberized or lignified periderm, sclereids (a network of terpenoid-filled resin ducts), and phenolic phloem parenchyma cells. Cabbage leaf curl virus infection and pathogenicity depend on the interaction between viral movement protein NSP, a nuclear shuttle protein, and the A. thaliana nuclear acetyltransferase AtNSI (nuclear shuttle protein interactor). A reverse yeast two-hybrid selection and deletion analysis was used by Carvalho et al. (2006) to identify NSI mutants that failed to interact with NSP; NSI expression patterns during development were also analysed, and found to be

developmentally regulated in a manner that resembles the sink-to-source transition. The authors conclude that NSP can inhibit NSI activity by interfering with its assembly into highly active complexes; furthermore NSP may both recruit NSI to regulate nuclear export of the viral genome and down-regulate NSI activity on cellular targets, perhaps to affect cellular differentiation and favor virus replication. Markham et al. (2006) attempted to identify the secondary metabolites that confer insect resistance (i.e. protein based resistance) in ferns and mosses. Five of 11 tested species yielded promising results: Ceratodon purpureus, Asplenium platyneuron, Anthyrium pycnocarpon, and Onoclea sensibilis extracts showed the most dramatic effect on leaf damage, larval mortality, and larval growth rates in the initial insect screenings at a protein concentration of 2 µg/µl. Insect-phloem relationships are detailed in Volume 57(4) of the Journal of Experimental Botany. Ajirlo et al. (2006) outlines transgenic strategies for inducing insect resistant ornamentals while Ferry et al. (2006) broaden the discussion to include other crops. Navarro et al. (2006) show that a flagellin-derived peptide induces a plant microRNA (miRNA) that negatively regulates messenger RNAs for the F-box auxin receptors TIR1, AFB2, and AFB3. Repression of auxin signaling restricts P. syringae growth, implicating auxin in disease susceptibility and miRNA-mediated suppression of auxin signaling in resistance. The perception of flagellins in Arabidopsis increases resistance to the bacterium Pseudomonas syringae. The amount of programmed cell death (PCD) triggered by P. syringae and protoporphyrin IX (PPIX) treatment is modulated by the chloroplast protein ACCELERATED CELL DEATH2 (ACD2) (Yao and Greenberg 2006). Danish growers adopted a dynamic climate regime mainly to reduce energy consumption in the greenhouse, but in doing so they also observed that problems with pests, especially thrips, diminished since they changed from the traditional rigid climate regime to a dynamic regime (Jakobsen et al. 2006). A review of polygalacturonase-inhibiting proteins or PGIPs, which are plant extracellular leucine-rich repeat proteins that specifically bind and inhibit fungal polygalacturonases is provided by Gomathi et al. (2006), di Matteo et al. (2006) and also by Federici et al. (2006). Cytokinin is a key factor in clubroot disease development in Arabidopsis. This fact was proved by Siemens et al. (2006) in transcriptome analysis of Arabidopsis clubroots, aberrant roots or clubs formed by infection with a biotrophic protist, Plasmodiophora brassicae. Using the Arabidopsis ATH1 genome array authors found that genes involved in cytokinin homeostasis (cytokinin synthases and cytokinin oxidases/dehydrogenases) were already strongly downregulated early in the infection process whereas genes involved in auxin homeostasis, such as nitrilases and members of the GH3 family, were upregulated. Verticillium wilt diseases caused by Verticillium spp., soil-borne pathogens in temperate and subtropical regions, affect some 200 hosts, including some ornamentals. A comprehensive review by Fradin and Thomma (2006) covers the taxonomy, host range and disease symptoms, pathogenicity and resistance. The copine gene BON1/CPN1, coding for a copine (calcium-dependent membrane-binding protein), in Arabidopsis has already shown the capacity to negatively regulate a disease

resistance (R) gene SNC1. Yang et al. (2006) went one step further by showing that three copine genes BON1, 2 and 3 stimulate cell growth and repress cell death. It is known that herbicide safeners protect monocot crops from herbicide injury but have little effect on weedy monocot or dicot species. Safeners induce localized induction of GSTs (glutathione S-transferases) in Arabidopsis roots, and this may explain why they are unable to provide herbicide tolerance to dicot plant species (DeRidder and Goldsbrough 2006). GSTs are important detoxification enzymes and their importance has been reviewed by Hossain et al. (2006). The importance of signalling molecules salicylic acid (SA) and jasmonic acid (JA) in plant defense signaling pathways has been reviewed by Beckers and Speol (2006) and in Volume III of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues.

Ajirlo SA, Jagadish B, Misra RL, Kumar PA (2006) Insect resistant transgenic floricultural crops. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol III, Global Science Books, Ltd, UK, pp 548-552 Beckers GJM, Speol SH (2006) Fine-tuning plant defence signalling: salicylate versus jasmonate. Plant Biology (Stuttg) 8, 1-10 Bellés JM, Garro R, Pallás V, Fayos J, Rodrigo I, Conejero V (2006) Accumulation of gentisic acid as associated with systemic infections but not with the hypersensitive response in plant-pathogen interactions. Planta 223, 500-511 Blackshaw RE, O'donovan JT, Harker KN, Clayton GW, Stougaard RN (2006) Reduced herbicide doses in field crops: A review. Weed Biology and Management 6, 10-17 Carvalho MF, Turgeon R, Lazarowitz SG (2006) The Geminivirus nuclear shuttle protein NSP inhibits the activity of AtNSI, a vascular-expressed Arabidopsis acetyltransferase regulated with the sink-to-source transition. Plant Physiology 140, 1317-1330 DeRidder BP, Goldsbrough PB (2006) Organ-specific expression of Glutathione S-Transferases and the efficacy of herbicide safeners in Arabidopsis. Plant Physiology 140, 167-175 di Matteo A, Bonivento D, Tsernoglou D, Federici L, Cervone F (2006) Polygalacturonase-inhibiting protein (PGIP) in plant defence: a structural view. Phytochemistry 67, 528-533 Federici L, Di Matteo A, Fernandez-Recio J, Tsernoglou D, Cervone F (2006) Polygalacturonase inhibiting proteins: players in plant innate immunity? Trends in Plant Science 11, 65-70 Ferry N, Edwards MG, Gatehouse J, Capell T, Christou P, Gatehouse AMR (2006) Transgenic plants for insect pest control: a forward looking scientific perspective. Transgenic Research 15, 13-19 Fradin EF, Thomma BPHJ (2006) Physiology and molecular aspects of Verticillium wilt diseases caused by V. dahliae and V. albo-atrum. Molecular Plant Pathology 7, 71-86 Gomathi V, Gayathri S, Anupama B, Teixeira da Silva JA, Gnanamanickam SS (2006) Molecular aspects of polygalacturonase-inhibiting proteins (PGIPs) in plant defense. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol III, Global Science Books, Ltd, UK, pp 373-379 Hossain MZ, Teixeira da Silva JA, Fujita M (2006) Differential roles of glutathionine S-transferases in oxidative stress modulation. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol III, Global Science Books, Ltd, UK, pp 108-116 Jakobsen L, Brogaard M, Enkegaard An, Brødsgaard HF, Aaslyng JM (2006) Dynamic and traditional greenhouse climate regimes: influx of thrips (Thysanoptera). HortScience 41, 389-393 Kim Y-M, Farrah S, Baney RH (2006) Silanol - A novel class of antimicrobial agent. Electronic Journal of Biotechnology 9, 176-180 Markham K, Chalk T, Stewart JrCN (2006) Evaluation of fern and moss protein-based defenses against phytophagous insects. International Journal of Plant Sciences 167, 111-117 Navarro L, Dunoyer P, Jay F, Arnold B, Dharmasiri N, Estelle M, Voinnet O, Jones JDG (2006) A plant miRNA contributes to antibacterial resistance by repressing auxin signaling. Science 312, 436-439 Ralph S, Park J-Y, Bohlmann J, Mansfield SD (2006) Dirigent proteins in conifer defense: gene discovery, phylogeny, and differential wound- and insect-induced expression of a family of DIR and DIR-like genes in Spruce (Picea spp.). Plant Molecular Biology 60, 21-40 Siemens J, Keller I, Sarx J, Kunz S, Schuller A, Nagel W, Schmülling T, Parniske M, Ludwig-Müller J (2006) Transcriptome analysis of Arabidopsis clubroots indicate a key role for cytokinins in disease development. Molecular Plant-Microbe Interactions 19, 480-494 Xing H, Lawrence CB, Chambers O, Davies HM, Everett NP, Li Q-Q (2006) Increased pathogen resistance and yield in transgenic plants expressing combinations of the modified antimicrobial peptides based on

indolicidin and magainin. Planta 223, 1024-1032 Yang S-H, Yang H, Grisafi P, Sanchatjate S, Fink GR, Sun Q, Hua J (2006) The BON/CPN gene family represses cell death and promotes cell growth in Arabidopsis. The Plant Journal 45, 166-179 Yao N, Greenberg JT (2006) Arabidopsis ACCELERATED CELL DEATH2 modulates programmed cell death. The Plant Cell 18, 397-411

Photosynthesis Organisms which tolerate full desiccation without suffering photo-oxidative damage in strong light are excellent models for studying photosystems, especially photosynthetic energy conservation and thermal dissipation of light energy. Heber et al. (2006) studied these processes in homoiohydric and poikilohydric autotrophs. Multiple members of the Arabidopsis heme oxygenase (HO) family (HY1, HO2­4) were analyxed for their important for synthesizing the bilin chromophore used to assemble photochemically active phytochromes (Emborg et al. 2006). Isotope screening (in which the 13CO2/12CO2 is determined), which is a simple test to determine the photosynthetic pathway used by plants, was suggested as being a method for the quality control of herbs and medicinal plants (Marchese et al. 2006). By identifying the photosynthetic type, authors claim that it is a new measure to avoid frauds and the introduction of contaminating plants. Novel micropropagation vessels were used to micropropagate Spathiphyllum plants under CO2 (3,000 ppm) enrichment at a low photon flux density (Teixeira da Silva et al. 2006). Almost all growth parameters were enhanced compared to control plants, and stronger, sturdier plants could be established, at a 100% survival rate with no somaclonal variation, in the greenhouse. Studies conducted by Balmer et al. (2006) suggest a mechanism whereby light is initially recognized as a thiol signal in chloroplasts, then as a sugar during transit to the sink, where it is converted again to a thiol signal. In this way, amyloplast (organelles in heterotrophic plant tissues that, among other biosynthetic activities, catalyze the synthesis and storage of copious amounts of starch) reactions in the grain can be coordinated with photosynthesis taking place in leaves. Several processes in biological systems are regulated by redox via thiol­disulfide exchange, a mechanism that is particularly widespread in plants, where almost 200 proteins have been linked to thioredoxin (Trx), a widely distributed small regulatory disulfide protein. Photosynthetic CO2 assimilation in C3 plants in hot, dry environments is moderated primarily by ribulose 1·5-bisphosphate carboxylase/oxygenase (Rubisco) because CO2 availability is restricted and photorespiration is stimulated. Raines (2006), using a combination of genetic engineering and transgenic technology, three approaches to reduce photorespiration have been taken; two of these focused on increasing the carboxylation efficiency of Rubisco either by reducing the oxygenase reaction directly or by manipulating the Rubisco enzyme by concentrating CO2 in the region of Rubisco through the introduction of enzymes of the C4 pathway. The third approach attempted to reduce photorespiration directly by manipulation of enzymes in this pathway. HT1 kinase is important for regulation of stomatal movements and its function is more pronounced in response to CO2 than it is to ABA or light. This conclusion was made after Hashimoto et al. (2006) discovered two allelic Arabidopsis

mutants (high leaf temperature 1; ht1-1 and ht1-2) that are altered in their ability to control stomatal movements in response to CO2. Peng et al. (2006), through mutant analyses, show that LOW PSII ACCUMULATION1 or LPA1 may be an integral membrane chaperone that is required for efficient PSII assembly, probably through direct interaction with the PSII reaction center protein D1.

Balmer Y, Vensel WH, Cai N, Manieri W, Schürmann P, Hurkman WJ, Buchanan BB (2006) A complete ferredoxin/thioredoxin system regulates fundamental processes in amyloplasts. Proceedings of the National Academy of Sciences USA 103, 2988-2993 Emborg TJ, Walker JM, Noh B, Vierstra RD (2006) Multiple heme oxygenase family members contribute to the biosynthesis of the phytochrome chromophore in Arabidopsis. Plant Physiology 140, 856-868 Hashimoto M, Negi J, Young J, Israelsson M, Schroeder JI, Iba K (2006) Arabidopsis HT1 kinase controls stomatal movements in response to CO2. Nature Cell Biology 8, 391-397 Heber U, Lange OL, Shuvalov VA (2006) Conservation and dissipation of light energy as complementary processes: homoiohydric and poikilohydric autotrophs. Journal of Experimental Botany 57, 1211-1223 Marchese JA, Ming LC, Ducatti C, Broetto F, Da Silva ET, Leonardo M (2006) Carbon isotope composition as a tool to control the quality of herbs and medicinal plants. Photosynthetica 44, 155-159 Peng L-W, Ma J, Chi W, Guo J, Zhu S, Lu Q, Lu C, Zhang L (2006) LOW PSII ACCUMULATION1 is involved in efficient assembly of Photosystem II in Arabidopsis thaliana. The Plant Cell 18, 955-969 Raines CA (2006) Transgenic approaches to manipulate the environmental responses of the C3 carbon fixation cycle. Plant, Cell and Environment 29, 331-339 Teixeira da Silva JA, Giang DDT, Tanaka M (2006) Photoautotrophic micropropagation of Spathiphyllum. Photosynthetica 44, 53-61

Phytoremediation Phytochelatins (PCs) are small metal-binding peptides, and are one of the plant's mechanisms to scavenge heavy metals, in addition to antioxidants, amino acids, organic acids, and tripeptide GSH; PCs function by chelating with heavy metals, particularly cadmium (Cd); the PC-Cd complex is then transported to the vacuole by an ATP binding cassette (ABC) type transporter (Ortiz et al. 1995). Bacopa monnieri, a wetland macrophyte and medicinally important Ayurvedic herb (producing bacosides and bacopasides; potent anti-oxidant, anti-convulsant and anti-depressant activities) produced PCs and several antioxidants in response to Cd stress (Mishra et al. 2006). N-containing metabolites, in particular proline, certain other amino acids and oligopeptides, as well as betaine, polyamines, and nicotianamine, frequently preferentially synthesized under heavy metal stress such as Cd, Cu, Ni, and Zn, are discussed by Sharma and Dietz (2006). The whole genome sequence data of ABC transporters were phylogenomically analysed by Schulz and Kolukisaoglu (2006). Twenty-two genes encoding the p-glycoprotein (PGP) subfamily are also ABC transporters, and recent studies of plant PGPs indicating that PGPs mediate the cellular and long-distance transport of the plant hormone auxin were highlighted by Geisler and Murphy (2006). Genes belonging to the multidrug resistance-associated protein (MRP, ABCC) subfamily of ABC transporters have been identified, and Klein et al. (2006) review and discuss the diverse functions of plant MRP-type ABC transporters and present an organ-related and developmental analysis of the expression of Arabidopsis MRPs using the publicly available full-genome chip data. The pleiotropic drug resistance (PDR) family of ABC transporters' particularity is that its members are found only in fungi and plants and have a reverse domain organization, i.e., the nucleotide binding domain precedes the transmembrane domain. Crouzet et al. (2006) explain that most of the plant PDR genes

so far characterized belong to subfamily I and have been shown to be involved in responses to abiotic and biotic stress, in the latter case, probably by transporting antimicrobial secondary metabolites to the cell surface while only a single subfamily II member has been characterized: induction of its expression by iron deficiency suggests its involvement in iron deficiency stress, thus, enlightening a new physiological role for a PDR gene. The mechanism of accumulation and membrane transport of secondary metabolites, such as alkaloids, terpenoids, polyphenols, quinones and many further compounds having combined structures of those groups, in particular, focusing on ATP-binding cassette transporters (ABC transporters) have been focussed by Yazaki (2006). Pteris vittata L, an arsenic hyperaccumulator, chlorophyll, protein and carotenoid contents increased when plants were placed under arsenic stress in Hoagland's hydroponic solution as compared to Pteris ensiformis, a non-arsenic hyperaccumulator (Singh et al. 2006).protection from oxidative damage in P. vittata was attributed to a greater level of ascorbate-glutathione pool. Details of the mechanisms that underlie arsenic stress combat have been detailed by members of this research group (Rathinasabapathi et al. 2006). The plant roots of several species (Spinacia oleracea L., Lycopersicon esculentum L., Lactuca sativa L., Pisum sativum L. and Lupinus albus L.) were shown to sequester ammonium, presumably in the vacuoles, and serves as an additional mechanism contributing to plant tolerance to ammonium nutrition (Cruz et al. 2006). Rylott et al. (2006) transformed A. thaliana to express a bacterial gene xplA encoding an RDX-degrading cytochrome P450. RDX, or hexahydro-1,3,5-trinitro-1,3,5-triazine, one of the most widely used military explosives, has raised concern owing to its toxicity and recalcitrance to degradation. The expression of xplA in landscape plants may provide a suitable remediation strategy for sites contaminated by this class of explosives. Pérez-de-Mora et al. (2006) applied seven treatments: four organic treatments (municipal waste compost, biosolid compost, leonardite and litter), one inorganic treatment (sugar beet lime) and two controls (control with plant cover and control without plant cover) to determine the effects of in situ remediation of a heavy metal (HM) contaminated soil on some soil chemical properties, microbial function and microbial structural diversity, all of which were affected after 18 months.

Crouzet J, Trombik T, Fraysse S, Boutry M (2006) Organization and function of the plant pleiotropic drug resistance ABC transporter family. FEBS Letters 508, 1123-1130 Cruz C, Bio AFM, Domínguez-Valdivia MD, Aparicio-Tejo PM, Lamsfus C, Martins-Loução MA (2006) How does glutamine synthetase activity determine plant tolerance to ammonium? Planta 223, 1068-1080 Geisler M, Murphy AS (2006) The ABC of auxin transport: The role of p-glycoproteins in plant development. FEBS Letters 508, 1094-1102 Klein M, Burlaand B, Martinoia E (2006) The multidrug resistance-associated protein (MRP/ABCC) subfamily of ATP-binding cassette transporters in plants. FEBS Letters 508, 1112-1122 Mishra S, Srivastava S, Tripathi RD, Govindarajan R, Kuriakose SV, Prasad MNV (2006) Phytochelatin synthesis and response of antioxidants during cadmium stress in Bacopa monnieri L. Plant Physiology and Biochemistry 44, 25-37 Ortiz DF, Ruscitli T, McCue KF, Ow DW (1995) Transport of metal binding peptides by HMT1, a fission yeast ABC-type vacuolar membrane protein. Journal of Biological Chemistry 270, 4721-728 Pérez-de-Mora A, Burgos P, Madejón E, Cabrera F, Jaeckel P, Schloter M (2006) Microbial community structure and function in a soil contaminated by heavy metals: effects of plant growth and different amendments. Soil Biology and Biochemistry 38, 327-341 Rathinasabapathi B, Ma LQ, Srivastava M (2006) Arsenic

hyperaccumulating ferns and their application to phytoremediation of arsenic contaminated sites. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol III, Global Science Books, Ltd, UK, pp 304-311 Rylott EL, Jackson RG, Edwards J, Womack GL, Seth-Smith HMB, Rathbone DA, Strand SE, Bruce NC (2006) An explosive-degrading cytochrome P450 activity and its targeted application for the phytoremediation of RDX. Nature Biotechnology 24, 216-219 Schulz B, Kolukisaoglu HU (2006) Genomics of plant ABC transporters: The alphabet of photosynthetic life forms or just holes in membranes? FEBS Letters 508, 1010-1016 Sharma SS, Dietz KJ (2006) The significance of amino acids and amino acid-derived molecules in plant responses and adaptation to heavy metal stress. Journal of Experimental Botany 57, 711-726 Singh N, Ma LQ, Srivastava M, Rathinasabapathi B (2006) Metabolic adaptations to arsenic-induced oxidative stress in Pteris vittata L and Pteris ensiformis L. Plant Science 166, 274­282 Yazaki K (2006) ABC transporters involved in the transport of plant secondary metabolites. FEBS Letters 508, 1183-1191

Touraine B (2006) Nitrate-dependent control of root architecture and N nutrition are altered by a plant growth-promoting Phyllobacterium sp. Planta 223, 591-603 Matsui T, Tsuchiya T (2006) A method to estimate practical radial oxygen loss of wetland plant roots. Plant and Soil 279, 119-128 Meunchang S, Panichsakpatana S, Weaver RW (2006) Tomato growth in soil amended with sugar mill by-products compost. Plant and Soil 280, 171-176

Plant-soil relationships Plants growing in flooded environments such as wetland plants develop mechanisms to deal with anaerobic conditions. To survive these anoxic conditions, many wetland plants develop aerenchyma or aerenchymatous lacunae; in addition the development of through-flow convection, driven by a pressure differential, provides aeration to underground/submerged parts. Radical oxygen loss (ROL) occurs from root tips, also providing a protective mechanism to the plant. Measuring ROL has not been easy until now. Matsui and Tsuchiya (2006) of Chiba University developed a practical method of measuring ROL in model plant Typha latifolia by introducing oxygen-free nitrogen gas and then measuring the emission colorimetrically. Their results demonstrated the capacity of this method to detect ROL, when more conventional methods such as the closed chamber/electrode method could not. Tomato shoot growth was enhaced 112% or 180% when plants were grown in sugar mill by-products compost with either uninoculated or inoculated (with N2-fixing bacteria), respectively (Meunchang et al. 2006). Even though there is no mention (nor experiment) of the effect on subsequent fruit harvest, this methodology provides a unique novel substrate for ornamental growers, especially in Australia, India, South Africa and Brazil, where sugar mills and sugar cane plantations are abundant. Ara-rhizotron is a novel, non-destructive method/structure developed by Devienne-Barret et al. (2006) to simultaneously study plant roots and shoots without negatively impacting shoot development during the analytical period. Using Arabidopsis, several advantages to conventional pots are shown. A plant growth-promoting rhizobacterium (PGPR) Phyllobacterium strain STM196, was shown to promote Arabidopsis plant development independent of the nitrogen source (Mantelin et al. 2006). Also of interest is the fact that the inhibition of Arabidopsis lateral root growth by high external NO3- is overridden by Phyllobacterium inoculation. Castagnone-Sereno (2006) provides a comprehensive review on root-knot nematodes of the genus Meloidogyne which are biotrophic plant parasites of major agricultural importance. These nematodes exhibit very variable modes of reproduction, from classical amphimixis to mitotic parthenogenesis, and this is the focus of the review.

Castagnone-Sereno P (2006) Genetic variability and adaptive evolution in parthenogenetic root-knot nematodes. Heredity 96, 282-289 Devienne-Barret F, Richard-Molard C, Chelle M, Maury O, Ney B (2006) Ara-Rhizotron: an effective culture system to study simultaneously root and shoot development of Arabidopsis. Plant and Soil 280, 253-266 Mantelin S, Desbrosses G, Larcher M, Tranbarger TJ, Cleyet-Marel JC,

Pollen development A subtraction cDNA library was prepared from the early stages of Nicotiana tabacum pollen development (from dyad till uninucleate stage) and 113 unique genes differentially expressed were identified, representing the largest collection of `early genes', among which 12 are anther-specific (Shary et al. 2006). The structure, organization and dynamic changes of the actin cytoskeleton in living, growing pollen tubes of Nicotiana tabacum and Lilium formosanum, using three different GFP-labeled actin-binding domains were studied, due to its importance in pollen tube growth (Wilsen et al. 2006). Zhao and Ren (2006), using Lilium davidii, showed how microinjection of wild type WT-Rop1Ps accelerated pollen tube elongation and induced actin bundles to form in the extreme tip region, indicating that Rop1Ps exert control over important aspects of tip morphology involving dynamics of the actin cytoskeleton that affect pollen tube elongation. Rop is the small GTPase of the Rho family in plants. Also in lily (Lilium longiflorum) Huang et al. (2006) found that LlANK is a ubiquitin ligase associated with membrane-enclosed organelles and required for polarized pollen tube growth. LIANK, derived from the lily ankyrin repeat-containing protein gene. The LlANK transcript is present in mature pollen and its level is significantly up-regulated during pollen germination and pollen tube growth, unlike most pollen mRNAs. LlANK, when fused to gfp and transiently expressed in pollen was found to be dominantly associated with membrane-enclosed organelles as well as the generative cell. Transient silencing of LlANK impaired pollen germination and tube growth. A genome-wide analysis of transporter genes expressed in the male gametophyte at four developmental stages was conducted on A. thaliana pollen (Bock et al. 2006). The distinct expression patterns of specific transporters and unknown polytopic proteins during microgametogenesis were reported and provide new insights for strategic mutant analyses necessary to integrate the roles of transporters and potential receptors with male gametophyte development. Honys et al. (2006) review male gametophyte development. Adler and Irwin (2006) used an original method employing dyed pollen donor flowers and sequences of four emasculated recipient flowers in field cages to estimate pollen transfer; the distylous plant Gelsemium sempervirens was the model plant.

Adler LS, Irwin RE (2006) Comparison of pollen transfer dynamics by multiple floral visitors: experiments with pollen and fluorescent dye. Annals of Botany 97, 141-150 Bock KW, Honys D, Ward JM, Padmanaban S, Nawrocki EP, Hirschi KD, Twell D, Sze H (2006) Integrating membrane transport with male gametophyte development and function through transcriptomics. Plant Physiology 140, 1205-1212 Honys D, Reák D, Twell D (2006) Male gametophyte development and function. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 76-87 Huang J, Chen F, Del Casino C, Autino A, Shen M, Yuan S, Peng J, Shi H, Wang C, Cresti M, Li Y (2006) An ankyrin repeat-containing protein, characterized as a ubiquitin ligase, is closely associated with membrane-enclosed organelles and required for pollen germination and pollen tube growth in lily. Plant Physiology 140, 1374-1383 Shary S, Kumar R, Guha-Mukherjee S (2006) Isolation of pollen early

genes and analysis of expression pattern during the development of male gametophyte. Plant Science 166, 417-25 Wilsen KL, Lovy-Wheeler A, Voigt B, Menzel D, Kunkel JG, Hepler PK (2006) Imaging the actin cytoskeleton in growing pollen tubes. Sexual Plant Reproduction 19, 51-62 Zhao H, Ren H (2006) Rop1Ps promote actin cytoskeleton dynamics and control the tip growth of lily pollen tube. Sexual Plant Reproduction 19, 83-91

Postharvest Although the apparent applications to cut flowers may not immediately be obvious, certainly the application to cut foliage may exist in the result that follows. Martínez-Romero et al. (2006) demonstrated how a coating of Aloe vera gel on sweet cherries could prolong their postharvest life by acting as barriers during processing, handling and storage. Further advantages of A. vera and advances in its biotechnology may be found in de Rodriguez 2006 publication. Traditionally, edible coatings are used to improve food appearance and conservation but there may exist no reports yet on their application to cut flowers or foliage. Due to the natural biocide activity of A. vera gel, or whether antimicrobial compounds are incorporated, either approach would potentially lead to the preservation of postharvest comodities without a deterioration in quality. Ornamental postharvest biologists are also referred to Cha and Chinnan's 2004 paper in which different compounds were used as edible coatings to prevent commodity weight loss, including wax, milk proteins, celluloses, lipids, starch, zein, and alginate. Chlorophyll catabolism leads to a loss of green color and yellowing during senescence; other possible effects may include tissue disruption, lipid peroxidation, protein degradation and the loss of antioxidant compounds (reviewed by Bouvier et al. and by Teixeira da Silva in Volume I of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. The use of UV-C to irradiate broccoli flower heads resulted in delayed yellowing, chlorophyll a and b degradation, and also an increase in pheophytins (antioxidant) during storage (Costa et al. 2006). Even though UV light negatively impacts plant tissues and causes decreased protein synthesis, impaired chloroplast function (Zsiros et al. 2006), and DNA damage, the concept of hormesis claims that a beneficial effect from application of a low or sublethal dose of an agent capable of inducing physical or chemical stress is possible (Luckey 1980). The use of UV-C has not hyet been reported for cut flowers. Of equal importance to flower postharvest biologists is the need to be able to measure flavonoid content in flowers and/or leaves and its changes during senescence. The use of Chlorophyll fluorescence by excitation with two radiation beams of different wavelengths is useful in the non-destructive quantitation of epidermal flavonoids in leaves, and was exemplified with broccoli (Bengtsson et al. 2006). Bruising, a type of subcutaneous damage caused without the rupture of the skin, is a commonly used term in fruit and vegetable postharvest, but rarely seen employed in flower or cut foliage postahrvest studies. Bruising appears to be the result of both physical injury and the subsequent breakdown of the cell wall components by the action of cell wall-related proteins, and even though the mechanisms are not completely known, they may be similar across all postharvest produce. CCD cameras, thermal heat imaging or even blue light lasers have all traditionally been used to detect bruising, and Van linden et al. (2006) propose a new methodology, an instrumented pendulum, to measure bruising. Their model plant (fruit) was tomato.

Severe flower wilting occurs in Petunia inflata petals following compatible pollination within 36 hours, including major changes in gene expression, providing an excellent model for investigation of petal senescence and programmed cell death. The xpression of a number of genes and various enzyme activities involved in the degradation and remobilization of macromolecules have previously been found to be upregulated during the early stages of petal senescence, but in a study by Xu et al. (2006) a highly upregulated gene encoding a cytochrome P450 was identified, suggesting that additional products of fatty acid metabolism may play important roles during programmed cell death. A very practical chapter on postharvest maintenance of cut flower commodities has been abdridged by Balas et al. (2006).

Balas J, Coronado PAG, Teixeira da Silva JA, Jayatilleke MP (2006) Supporting post-harvest performance of cut-flowers using fresh-flower-refreshments and other vase-water-additives. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol IV, Global Science Books, Ltd, UK, pp 612-629 Bengtsson GB, Schöner R, Lombardo E, Schöner J, Borge GIA, Bilger W (2006) Chlorophyll fluorescence for non-destructive measurement of flavonoids in broccoli. Postharvest Biology and Technology 39, 291-298 Cha DS, Chinnan M (2004) Biopolymer-based antimicrobial packaging: a review, Critical Reviews in Food Science and Nutrition 44, 223-237 Costa L, Vicente AR, Civello PM, Chaves AR, Martínez GA (2006) UV-C treatment delays postharvest senescence in broccoli florets. Postharvest Biology and Technology 39, 204-210 de Rodríguez DJ, Angulo-Sánchez JL, Teixeira da Silva JA, Aguilar-Gonzalez CN (2006) Review of Aloe species' medicinal properties and bioactive compounds. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol IV, Global Science Books, Ltd, UK, pp 460-471 Luckey TD (1980) Hormesis with Ionizing Radiation, CRC Press, Boca Raton Martínez-Romero D, Alburquerque N, Valverde JM, Guillén F, Castillo S, Valero D, Serrano M (2006) Postharvest sweet cherry quality and safety maintenance by Aloe vera treatment: A new edible coating. Postharvest Biology and Technology 39, 93-100 Van Linden V, De Ketelaere B, Desmet M, De Baerdemaeker J (2006) Determination of bruise susceptibility of tomato fruit by means of an instrumented pendulum. Postharvest Biology and Technology 40, 7-14 Xu Y, Ishida H, Reisen D, Hanson MR (2006) Upregulation of a tonoplast-localized cytochrome P450 during petal senescence in Petunia inflata. BMC Plant Biology 6, 8 Zsiros O, Allakhverdiev SI, Higashi S, Watanabe M, Nishiyama Y, Murata N (2006) Very strong UV-A light temporally separates the photoinhibition of photosystem II into light-induced inactivation and repair. Biochimica et Biophysica Acta ­ Bioenergetics 1757, 123-129

Programmed Cell Death (PCD) A physiological explanation why salt stress should result in reduced fertility was provided in experiments conducted with Arabidopsis seeds, with initial anatomical changes occurring in the female gametophyte of an aborting ovule, followed by, within four hours, the dissipation of the mitochondrial membrane potential and a subsequent accumulation of reactive oxygen species (ROS) in the gametophyte (Hauser et al. 2006). Drury and Gallois (2006) provide a comprehensive review on PCD in plants and flowers. Salt stress has been tackled from several case study-points of view in the Volume 57, Issue 5 of the Journal of Experimental Botany while PCD in flowers has been tackled by Rogers (2006). In some exquisite experiments, Watanabe and Lam (2006) demonstrate how BI-1 is an attenuator for cell death progression triggered by both biotic (infiltration of leaf tissues with a PCD-inducing fungal toxin fumonisin B1, FB1) and abiotic (heat shock) types of cell death signals in Arabidopsis. BI-1 or Bax inihibitor-1 is proposed to be a cell death suppressor that is conserved in both animals and plants. Wang and Liu (2006) found that, as in animal and yeast

systems, ribonucleotide reductase (RNR) is important in catalyzing a rate-limiting step in the production of deoxyribonucleotides needed for DNA replication and repair, and that the detection of DNA damage triggers cell death mechanisms.

Drury GE, Gallois P (2006) Programmed Cell Death in plants and flowers. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 141-156 Hauser BA, Sun K, Oppenheimer DG, Sage TL (2006) Changes in mitochondrial membrane potential and accumulation of reactive oxygen species precede ultrastructural changes during ovule abortion. Planta 223, 492-499 Rogers HJ (2006) Programmed Cell Death in floral organs: how and why do flowers die? Annals of Botany 97, 309-315 Wang C-X, Liu Z-C (2006) Arabidopsis ribonucleotide reductases are critical for cell cycle progression, DNA damage repair, and plant development. The Plant Cell 18, 350-365 Watanabe N, Lam E (2006) Arabidopsis Bax inhibitor-1 functions as an attenuator of biotic and abiotic types of cell death. The Plant Journal 46, 884-894

Roots, rooting and root development Simple application of IBA powder (Sigma) at 4-16 g/l to Grevillea `Royal Mantle' cuttings showed almost double the adventitious rooting percentage as controls (Krisantini et al. 2006). Rooting was also earlier in IBA-applied cuttings. IAA was also effective, but not as much as IBA. Grevillea is an important landscape ornamental native to Australia. The importance of pH in the rooting of cuttings has been dealt with by Alam and Chong (2006). Knotted1-like TALE homeodomain proteins play an important role in the development of the Arabidopsis shoot apical meristem and are also part of a complex regulatory network of protein interactions. Truernit et al. (2006) show how the knotted1-like genes KNAT1, KNAT3, KNAT4, and KNAT5 may be involved in Arabidopsis root development, being expressed in different spatially restricted patterns along the longitudinal root axis and in lateral root primordia. Roots show a higher level of transgene transcripts of silenced-transgenic Nicotiana benthamiana plants than leaves and these transcripts were inversely related to the accumulation of small interfering RNAs (siRNAs); the suggestion that RNA silencing is less active in roots than in leaves is supported by Andika et al. (2006) by the fact that there are lower transgene methylation levels at non-symmetrical CpNpN context but not at symmetrical CpG or CpNpG context. An Arabidopsis gene (AtSFLs) similar to the S-locus F-box genes involved in S-RNase-based self-incompatibility was shown to increase lateral root production when a T-DNA was inserted into CEG (CEGENDUO); lateral root production also increased with a downregulation of CEG by RNAi (Dong et al. 2006). Exogenously-applied NAA also inuced CEG, and together with other results involving auxins and auxin inhibitors, it was concluded that CEG is an auxin-inducible gene. In separate studies ARABIDILLO-1 and -2, Arabidopsis genes that show greatest sequence homology to Armadillo/-catenin, were shown to promote lateral root development (Coates et al. 2006). Armadillo/-catenin and related proteins have important functions during animal and Dictyostelium development, regulating cell differentiation, proliferation, and adhesion. The latest developments in root development have been reviewed by Schiefelbein and Lee (2006) in which a novel regulatory circuit that has recently been identified, which includes a lateral inhibition pathway and a feedback loop that

enables intercellular communication and ensures that two distinct cell types arise in an appropriate pattern, has been emphasized. Zhu et al. (2006) show how both methyl jasmonate (MeJA) and jasmonic acid (JA) have a pronounced effect on promoting root hair formation. Briggs et al. (2006) have started important initial studies to characterize the novel, plant-specific BRX (BREVIS RADIX) gene family, which has been identified as a modulator of root growth through a naturally occurring loss-of-function allele. Xu et al. (2006) investigated a local regeneration response in Arabidopsis roots. Laser-induced wounding disrupted the flow of auxin ­ a cell-fate-instructive plant hormone ­ in root tips, and they demonstrated that resulting cell-fate changes required the PLETHORA, SHORTROOT, and SCARECROW transcription factors which regulate the expression and polar position of PIN auxin efflux-facilitating membrane proteins to reconstitute auxin transport in renewed root tips. Root gravitropism requires the coordinated, asymmetric distribution of the phytohormone auxin within the root meristem, and depends on the concerted activities of PIN proteins and AUX1 members of the auxin transport pathway. Abas et al. (2006) show that intracellular trafficking and proteasome activity combine to control PIN2 degradation during root gravitropism and that redistribution of auxin during the gravitropic response may be involved in the regulation of PIN2 protein. Perera et al. (2006) generated transgenic A. thaliana plants expressing the human type I inositol polyphosphate 5-phosphatase (InsP 5-ptase), and enzyme that specifically hydrolyzes InsP3, which has been implicated in the early signaling events of plants linking gravity sensing to the initiation of the gravitropic response. Authors noted that with gravistimulation, InsP3 levels in inflorescence stems of transgenic plants show no detectable change, whereas in wild-type plant inflorescences, InsP3 levels increase approximately 3-fold within the first 5 to 15 min of gravistimulation, preceding visible bending, suggesting a universal role for InsP3 in the gravity signal transduction cascade of plants. Arabidopsis primary root growth inhibition and increased lateral root formation occur in response to phosphorus (P) limitation. A screen for identifying Arabidopsis mutants that fail to arrest primary root growth when grown under low P conditions was designed by Sánchez-Calderón et al. (2006), and proves useful in deepening the knowledge of the genetic mechanisms that regulate root architectural responses to P availability. Cell proliferation and accumulation and cell differentiation around the parental root axis vary with the locations of branch root attachments. Cell differentiation is spatially related to the differentiation of protoxylem in the parental root axis. These position/structure effects were described by Paolillo (2006) and divided into 4 categories: (1) low accumulation of secondary xylem on the side of the branch root, (2) formation of depressions where branch roots emerge, (3) accumulation of parenchyma along loci where branch roots are formed, and (4) lobing of the parental axis in coordination with branch root attachments. Costa and Shaw (2006) show by 3-D FISH on intact root epidermal tissue that alternative states of chromatin organization around the GL2 (GLABRA2, a homoeodomain transcription

factor) locus are required to control position-dependent cell-type specification. When, as a result of an atypical cell division, a cell is displaced from a hair file into a non-hair file, it switches fate. Nakajima et al. (2006) noted that that SPR1 and SP1Ls act redundantly in maintaining the cortical microtubules' organization essential for anisotropic (=helical) cell growth, and that the helical growth phenotype of spr1 results from a partially compromised state of cortical MTs. Arabidopsis spiral1 (spr1) mutants show a right-handed helical growth phenotype in roots and etiolated hypocotyls due to impaired directional growth of rapidly expanding cells. The Arabidopsis embryonic root meristem is initiated by the specification of a single cell, the hypophysis, and event that critically requires the antagonistic auxin response regulators MONOPTEROS and BODENLOS whose mechanism of action is unknown. Weijers et al. (2006) show that these proteins interact and transiently act in a small subdomain of the proembryo adjacent to the future hypophysis where they promote transport of auxin, which then elicits a second response in the hypophysis itself, suggesting that hypophysis specification is not the direct result of a primary auxin response but rather depends on cell-to-cell signaling triggered by auxin in adjacent cells. Konishi and Sugiyama (2006) isolated a temperature-sensitive mutant in A. thaliana, root primordium defective 1 (rpd1) that cannot produce adventitious roots in response to exogenously supplied auxin. In addition, disruption of the RPD1 gene by a T-DNA insertion caused embryogenesis arrest at the globular to transition stages, leading authors to hypothesize that RPD1 is important in the maintenance of active cell proliferation. Ran is an evolutionarily conserved eukaryotic GTPase. Wang et al. (2006) found that when they overexpressed a wheat Ran GTPase homologous gene, TaRAN1, there was an increase in the proportion of cells in the G2 phase of the cell cycle, resulting in an elevated mitotic index and prolonged life cycle and to an increase in primordial tissue, reduced number of lateral roots, and stimulated hypersensitivity to exogenous auxin in both Arabidopsis and rice. Through studies of the A. thaliana reb1-1 (root epidermal bulger1-1), a mutation that affects the XyG structure, but not that of pectic polysaccharides, Nguema-Ona et al. (2006) further provided support of the fact that biosynthesis of Gal (D-Galactose) as well as galactosylation of complex polysaccharides is regulated at the polymer level. reb1-1 mutants are typified by a reduced root elongation rate and bulging of trichoblast cells.

Abas L, Benjamins R, Malenica N, Paciorek T, Wisniewska J, Moulinier­Anzola JC, Sieberer T, Friml J, Luschnig C (2006) Intracellular trafficking and proteolysis of the Arabidopsis auxin-efflux facilitator PIN2 are involved in root gravitropism. Nature Cell Biology 8, 249-256 Alam MZ, Chong C (2006) Rooting of cuttings and role of pH. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol III, Global Science Books, Ltd, UK, pp 1-11 Andika IB, Kondo H, Rahim MD, Tamada T (2006) Lower levels of transgene silencing in roots is associated with reduced DNA methylation levels at non-symmetrical sites but not at symmetrical sites. Plant Molecular Biology 60, 423-435 Briggs GC, Mouchel CF, Hardtke CS (2006) Characterization of the plant-specific BREVIS RADIX gene family reveals limited genetic redundancy despite high sequence conservation. Plant Physiology 140, 1306-1316 Coates JC, Laplaze L, Haseloff J (2006) Armadillo-related proteins promote lateral root development in Arabidopsis. Proceedings of the

National Academy of Sciences USA 103, 1621-1626 Costa S, Shaw P (2006) Chromatin organization and cell fate switch respond to positional information in Arabidopsis. Nature 439, 493-496 Dong L, Wang L, Zhang Y, Zhang Y, Deng X, Xue Y (2006) An auxin-inducible F-Box protein CEGENDUO negatively regulates auxin-mediated lateral root formation in Arabidopsis. Plant Molecular Biology 60, 599-615 Konishi M, Sugiyama M (2006) A novel plant-specific family gene, ROOT PRIMORDIUM DEFECTIVE 1, is required for the maintenance of active cell proliferation. Plant Physiology 140, 591-602 Krisantini S, Johnston M, Williams RR, Beveridge C (2006) Adventitious root formation in Grevillea (Proteaceae), an Australian native species. Scientia Horticulturae 107, 171-175 Nakajima K, Kawamura T, Hashimoto T (2006) Role of the SPIRAL1 gene family in anisotropic growth of Arabidopsis thaliana. Plant and Cell Physiology 47, 513-522 Nguema-Ona E, Andème-Onzighi C, Aboughe-Angone S, Bardor M, Ishii T, Lerouge P, Driouich A (2006) The reb1-1 mutation of Arabidopsis. Effect on the structure and localization of Galactose-containing cell wall polysaccharides. Plant Physiology 140, 1406-1417 Paolillo JrDJ (2006) On the structural relationships of branch roots and their parental root axes in secondary growth. International Journal of Plant Sciences 167, 47-57 Perera IY, Hung C-Y, Brady S, Muday GK, Boss WF (2006) A universal role for Inositol 1,4,5-Trisphosphate-mediated signaling in plant gravitropism. Plant Physiology 140, 746-760 Sánchez-Calderón L, López-Bucio J, Chacón-López A, GutiérrezOrtega A, Hernández-Abreu E, Herrera-Estrella L (2006) Characterization of low phosphorus insensitive mutants reveals a crosstalk between low phosphorus-induced determinate root development and the activation of genes involved in the adaptation of Arabidopsis to phosphorus deficiency. Plant Physiology 140, 879-889 Schiefelbein J, Lee MM (2006) A novel regulatory circuit specifies cell fate in the Arabidopsis root epidermis. Physiologia Plantarum 126, 503-510 Truernit E, Siemering KR, Hodge S, Grbic V, Haseloff J (2006) A map of KNAT gene expression in the Arabidopsis root. Plant Molecular Biology 60, 1-20 Wang X, Xu Y, Han Y, Bao S, Du J, Yuan M, Xu Z, Chong K (2006) Overexpression of RAN1 in rice and Arabidopsis alters primordial meristem, mitotic progress, and sensitivity to auxin. Plant Physiology 140, 91-101 Weijers D, Schlereth A, Ehrismann JS, Schwank G, Kientz M, Jürgens G (2006) Auxin triggers transient local signaling for cell specification in Arabidopsis embryogenesis. Developmental Cell 10, 265-270 Xu J, Hofhuis H, Heidstra R, Sauer M, Friml J, Scheres B (2006) A molecular framework for plant regeneration. Science 311, 385-388 Zhu C, Gan L, Shen Z, Xia K (2006Interactions between jasmonates and ethylene in the regulation of root hair development in Arabidopsis. Journal of Experimental Botany 57, 1299-1308

Secondary metabolites/bioreactors/hairy roots A biotic elicitor, yeast extract (YE, 200 mg/L) and an abiotic elicitor, Ag+ (15 M) were both shown to increase the production of rosmarinic acid in Salvia miltorrhiza hairy root production (Yan et al. 2006). Buer et al. (2006) looked at how ethylene affected the gravitropic response in Arabidopsis wild-type Columbia root gravitropism. Among other physiological responses tested, that which is of particular interest to this section, involves the use of the ethylene precursor 1-aminocyclopropane carboxylic acid (ACC). ACC treatment induced flavonoid accumulation in tt4(2YY6) seedlings (which have a null mutation in the gene encoding chalcone synthase) root tips, but not in ein2-5 and etr1-3, ethylene-insensitive mutants. One of the two primary conclusions was that ACC inhibition of gravity response occurs through altering flavonoid synthesis, and this may have an impact on secondary metabolite bioreactors or hairy root cultures should there be an accumulation of ethylene. The flavonoid pathway is positively regulated by MAX1, a specific repressor of vegetative axillary bud outgrowth in Arabidopsis since the flavonoidless state leads to lateral outgrowth in Arabidopsis (Lazar and Goodman 2006). MAX1 is implicated in synthesis of the carotenoid-derived branch regulator(s) from the root, and thus likely links long-distance signaling with local control of bud outgrowth. Rischer et al. (2006) provide a comprehensive profiling

analysis, using genome-wide functional genomics approaches, of the Madagascar periwinkle (Catharanthus roseus), a source of the anticancer drugs vinblastine and vincristine. The importance of C. roseus cultures for studying secondary metabolite production as a model system has been highlighted in three volumes of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issue. Using a green-liver model, Subramanian et al. (2006) show how two axenic plant systems (A. thaliana and C. roseus) to show how hydroxylamines are unequivocally formed by plant transformation of TNT (2,4,6-Trinitrotoluene), a nitroaromatic found at varying concentrations at munitions production facilities and military training and testing sites worldwide. Plant volatiles play several important biochemical roles. The 10 February issue of Science is dedicated to a closer understanding of plant volatiles and their important biological roles. Kaiser (2006) illustrates how effectively certain plants and fungi can mimic each other, encroaching on their insect partnerships by using volatile signals. Pichersky et al. (2006) describe the biochemistry and the evolutionary forces that combine to produce the complex suite of volatiles while Baldwin et al. (2006) explain how plants "spy" on their neighbours to adjust their own reactions to ecosystem changes. A detailed understanding of coumarin synthesis in plants is still lacking, and in order to bridege than gap, Kai et al. (2006) analyzed coumarins in A. thaliana ecotype Columbia mutants that carried a T-DNA insertion within the gene encoding the cytochrome P450, CYP98A3, which catalyzes 3-hydroxylation of p-coumarate units in the phenylpropanoid pathway. High levels of scopoletin and its -d-glucopyranoside, scopolin, are found in wild-type roots. Bioreactors for secondary metabolite production via the action of Agrobacterium rhizogenes has been reviewed by Figueiredo et al. (2006) and Guillon et al. (2006), as plant factories for ornamental plant production by Chakrabarty and Paek (2006).

Baldwin IT, Halitschke R, Paschold A, von Dahl CC, Preston CA (2006) Volatile signaling in plant-plant interactions: "talking trees" in the genomics era. Science 311, 812-815 Buer CS, Sukumar P, Muday GK (2006) Ethylene modulates flavonoid accumulation and gravitropic responses in roots of Arabidopsis. Plant Physiology 140, 1384-1396 Figueiredo AC, Barroso JG, Pedro LG, Scheffer JJC (2006) Potentialities of hairy root cultures for in vitro essential oil production. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 478-486 Guillon S, Trémouillaux-Guiller J, Pati PK, Rideau M, Gantet P (2006) Hairy root research: recent scenario and exciting prospects. Current Opinion in Plant Biology 9, 341-346 Kai K, Shimizu B, Mizutani M, Watanabe K, Sakata K (2006) Accumulation of coumarins in Arabidopsis thaliana. Phytochemistry 67, 379-386 Kaiser R (2006) Flowers and fungi use scents to mimic each other. Science 311, 806-807 Lazar G, Goodman HM (2006) MAX1, a regulator of the flavonoid pathway, controls vegetative axillary bud outgrowth in Arabidopsis. Proceedings of the National Academy of Sciences USA 103, 472-476 Paek KY, Chakrabarty D (2006) Application of bioreactor systems for mass propagation of horticultural plants. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 472-477 Pichersky E, Noel JP, Dudareva N (2006) Biosynthesis of plant volatiles: nature's diversity and ingenuity. Science 311, 808-811 Rischer H, Oresic M, Seppänen-Laakso T, Katajamaa M, Lammertyn F, Ardiles-Diaz W, Van Montagu MCE, Inzé D, Oksman-Caldentey KM, Goossens A (2006) Gene-to-metabolite networks for terpenoid indole alkaloid biosynthesis in Catharanthus roseus cells. Proceedings of the National Academy of Sciences USA 103, 5614-5619 Subramanian M, Oliver DJ, Shanks JV (2006) TNT phytotransformation pathway characteristics in Arabidopsis: role of aromatic hydroxylamines.

Biotechnology Progress 22, 208-216 Yan Q, Shi M, Ng J, Wu J-Y (2006) Elicitor-induced rosmarinic acid accumulation and secondary metabolism enzyme activities in Salvia miltiorrhiza hairy roots. Plant Science 166, 853-858

Seeds DNA methylation (5-methylcytosine) in plants occurs at CpG dinucleotides, maintained by METHYLTRANSFERASE1 (MET1). Plants also have DNA methylation at CpNpG and CpNpN sites, maintained, in part, by the CHROMOMETHYLASE3 (CMT3) DNA methyltransferase. Xiao et al. (2006) show that A. thaliana embryos with loss-of-function mutations in MET1 and CMT3 develop improperly, display altered planes and numbers of cell division, and have reduced viability. In addition, genes that specify embryo cell identity are misexpressed, and auxin hormone gradients are not properly formed in abnormal met1 embryos. These evidences point to the essential need of methylation for proper embryogenic development and seed viability. Paternal allele silencing in the endosperm of Arabidopsis seeds is discussed by Gehring et al. (2006). Briefly an Arabidopsis Polycomb group gene, MEDEA (MEA) is imprinted in the endosperm. The MEA maternal allele is expressed, and this expression is controlled by DEMETER (DME), a DNA glycosylase, and by METHYLTRANSFERASE I (MET1), which maintains CG methylation at the MEA locus. The MEA paternal allele, on the other hand is silenced by Polycomb group proteins that are expressed from the maternal genome, including MEA. In this way, MEA imprinting is maintained in the endosperm. Baroux et al. (2006) go further by showing how MEA regulates its own imprinted expression by down-regulating the maternal allele around fertilization and maintainng the paternal allele silent later during seed development. Autorepression of the maternal MEA allele is direct and independent of the MEA­FIE (FERTILIZATION-INDEPENDENT ENDOSPERM) PcG complex. The LATE EMBRYOGENESIS ABUNDANT (LEA) genes encode a large and diverse family of proteins during seed maturation. LEA gene expression studies and importance for seed development have been reviewed by Baumbusch (2006). Manfre et al. (2006) extend the importance of group 1 LEA proteins in seed development as buffers of the water loss during embryo maturation. Reyes et al. (2006) showed that tyrosine dephosphorylation is a key regulatory mechanism in postgermination arrest of A. thaliana L. seed development mediated by ABA. Proteinase inhibitor II proteins (PIN2) are serine proteinase inhibitors found in the Solanaceae and are shown to be essential for seed development (Sin et al. 2006a 2006b). Kasumoto et al. (2006) show, using Striga asiatica seeds, how three carotenoid biosynthesis inhibitors, fluridone, norflurazon and diflufenican affect seed germination. Fascinating results indicate that fluridone and norflurazon shortened the conditioning period required before S. asiatica seeds would germinate after exposure to the germination stimulant strigol, and prevented the inhibitory effects of both light and supraoptimal temperature (40°C) on seed germination. Moreover, treatment with fluridone or norflurazon after conditioning in water induced seed germination in a manner similar to the effect of natural germination stimulants. Diflufenican did not show similar positive effects. Authors

suggest that fluridone and norflurazon, which have various effects on the germination of S. asiatica seeds, and which formed haustorium-like structures on seedlings without the involvement of haustorium inducing factors, might be of importance for controling root parasites. An interesting mini-review of some of these compunds and their effects on seed germination is provided. Analysis of HAL3A and HAL3B via comparative genomics, and by using T-DNA knockout mutants of two CoA biosynthetic genes demonstrated the critical role of CoA biosynthesis during early postgerminative growth (Rubio et al. 2006). The importance of comparative genomics as a tool for gene discovery has been abridged by Windsor and Mitchell-Olds (2006). Apomixis is a mode of asexual reproduction through seed in which embryo sacs and embryos are produced in ovules without meiotic reduction or egg cell fertilisation. Progeny produced by apomixis are clonal replicas of a mother plant. Barcaccia et al. (2006) use molecular markers to determine levels of genetic variation within and relationship among ecotypes of the facultative apomict Hypericum perforatum. Apomixis has been reviewed by Carneiro et al. (2006). Li et al. (2006) show how seed anatomy, light, and plant-to-plant variation influence the content and measurement of oil in Arabidopsis seeds. LEAFY COTYLEDON1 or LEC1, together with LEC2 and FUSCA3 play key roles in processes that occur during both the morphogenesis and maturation phases in Arabidopsis. Fambrini et al. (2006) discovered and characterized a LEC1-type gene in Helianthus annuus LEAFY COTYLEDON1-LIKE or HaL1L. New genomic sequences and transposons were identified by de Diego et al. (2006) using cDNA-AFLP analysis. Cervantes (2006) reviews the role of ethylene in seed germination.

Barcaccia G , Arzenton F, Sharbel TF, Varotto S, Parrini P , Lucchin M (2006) Genetic diversity and reproductive biology in ecotypes of the facultative apomict Hypericum perforatum L. Heredity 96, 322-334 Baroux C, Gagliardini V, Page DR, Grossniklaus U (2006) Dynamic regulatory interactions of Polycomb group genes: MEDEA autoregulation is required for imprinted gene expression in Arabidopsis. Genes and Development 20, 1081-1086 Baumbusch LO (2006) Genetic control of plant embryogenesis and embryo dormancy in Arabidopsis. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 417-428 Carneiro VTC, Dusi DMA, Ortiz JPA (2006) Ethylene in seed germination and early root development. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 564-571 Cervantes E (2006) Ethylene in seed germination and early root development. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 417-428 de Diego JG, Rodríguez FD, Rodríguez Lorenzo JL, Grappin P, Cervantes E (2006) cDNA-AFLP analysis of seed germination in Arabidopsis thaliana identifies transposons and new genomic sequences. Journal of Plant Physiology 163, 452-462 Fambrini M, Durante C, Cionini G, Geri C, Giorgetti L, Michelotti V, Salvini M, Pugliesi C (2006) Characterization of LEAFY COTYLEDON1-LIKE gene in Helianthus annuus and its relationship with zygotic and somatic embryogenesis. Development Genes and Evolution 216, 253-264 Gehring M, Huh JH, Hsieh T-F, Penterman J, Choi Y, Harada JJ, Goldberg RB, Fischer RL (2006) DEMETER DNA glycosylase establishes MEDEA Polycomb gene self-imprinting by allele-specific demethylation. Cell 124, 495-506 Kusumoto D, Chae SH, Mukaida K, Yoneyama K, Yoneyama K, Joel DM, Takeuchi Y (2006) Effects of fluridone and norflurazon on conditioning and germination of Striga asiatica seeds. Plant Growth Regulation 48, 73-78 Li Y-H, Beisson F, Pollard M, Ohlrogge J (2006) Oil content of Arabidopsis seeds: The influence of seed anatomy, light and plant-to-plant variation. Phytochemistry 67, 904-915 Manfre AJ, Lanni LM, Marcotte WRJr (2006) The Arabidopsis group 1

LATE EMBRYOGENESIS ABUNDANT protein ATEM6 is required for normal seed development. Plant Physiology 140, 140-149 Reyes D, Rodríguez D, Nicolás G, Nicolás C (2006) Evidence of a role for tyrosine dephosphorylation in the control of postgermination arrest of development by abscisic acid in Arabidopsis thaliana L. Planta 223, 381-385 Rubio S, Larson TR, Gonzalez-Guzman M, Alejandro S, Graham IA, Serrano R, Rodriguez PL (2006) An Arabidopsis mutant impaired in Coenzyme A biosynthesis is sugar dependent for seedling establishment. Plant Physiology 140, 830-843 Sin S-F, Yeung E-C, Chye M-L (2006a) Downregulation of Solanum americanum genes encoding proteinase inhibitor II causes defective seed development. The Plant Journal 45, 58-70 Sin S-F, Yeung E-C, Chye M-L (2006a) Expression of Solanum americanum genes encoding proteinase inhibitor II is essential for seed development. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 447-453 Windsor AJ, Mitchell-Olds T (2006) Comparative genomics as a tool for gene discovery. Current Opinion in Biotechnology 17, 161-167 Xiao W W-Y, Custard KD, Brown RC, Lemmon BE, Harada JJ, Goldberg RB, Fischer RL (2006) DNA methylation is critical for Arabidopsis embryogenesis and seed viability. The Plant Cell 18, 805-814

Senescence One of the limitations that hinders the export of ornamental commodities is dark-induced senescence. Parallels between both light- and dark-induced senescence mechanisms exist (Kleber-Janke and Krupinska 1997, He et al. 2001, Buchanan-Wollaston et al. 2003 2005). The up-regulation of many senescence-associated genes (SAGs) and chlorophyll breakdown characterize both light- and dark-induced senescence. Transcription factors have also been shown to induce senescence (Chen et al. 2002, Yoshida 2003). Rosenvasser et al. (2006) applied GA3, which inhibited Pelargonium cutting leaf senescence, possibly not only by reducing ROS (reactive oxygen species) levels, but also by interfering with senescence regulation, although the mechanism remains unknown. Ethylene, one of the most important phytohormones involved in the regulation of many cellular and developmental processes in plants through a signaling pathway conserved in monocots and dicots, including senescence, has been recently reviewed (Chen et al. 2005) and updated (Etheridge et al. 2006). Auxin response factors (ARFs) are believed to be involved in cross-talk between ethylene and auxin, and analysis of two auxin-resistant mutants isolated from forward genetic screens, arf19 and arf7 mutants, showed that the differences in expression level/pattern rather than differences in protein sequences between the two ARFs determined the relative contribution of the two ARFs in auxin signaling and plant development; furthermore arf19 has also ethylene-insensitive roots and ARF19 expression is induced by ethylene treatment (Li et al. 2006). Senescence was shown to initiate in gladiolus tepals with an increase in endogenous H2O2 level resulting directly from a programmed down-regulation of APX (ascorbate peroxidase) enzyme activity (Hossain et al. 2006). Physiological and genetic mechanisms of senescence and floral abscission have been reviewed in Volume I of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issue.

Buchanan-Wollaston V, Earl S, Harrison E, Mathas E, Navabpour S, Page T, Pink D (2003) The molecular analysis of leaf senescence - a genomics approach. Plant Biotechnology Journal 1, 3-22 Buchanan-Wollaston V, Page T, Harrison E, Breeze E, Lim PO, Nam HG, Lin J-F, Wu S-H, Swidzinski J, Ishizaki K, Leaver CJ (2005) Comparative transcriptome analysis reveals significant differences in gene expression and signalling pathways between developmental and dark/starvation-induced senescence in Arabidopsis. Plant Journal 42, 567-585

Chen YF, Etheridge N, Schaller GE (2005) Ethylene signal transduction. Annals of Botany 95, 901-915 Chen WQ, Provart NJ, Glazebrook J, Katagiri F, Chang HS, Eulgem T, Mauch F, Luan S, Zou G, Whitham SA, Budworth PR, Tao Y, Xie Z, Chen X, Lam S, Kreps JA, Harper JF, Si Ammour A, Mauch Mani B, Heinlein M, Kobayashi K, Hohn T, Dangl JL, Wang X, Zhu T (2002) Expression profile matrix of Arabidopsis transcription factor genes suggests their putative functions in response to environmental stresses. Plant Cell 14, 559-574 Etheridge N, Hall BP, Schaller GE (2006) Progress report: ethylene signaling and responses. Planta 223, 387-391 He Y, Tang W, Swain JD, Green AL, Jack TP, Gan S (2001) Networking senescence-regulating pathways by using Arabidopsis enhancer trap lines. Plant Physiology 126, 707-716 Hossain Z, Kalam Azad Mandal A, Kumar Datta S, Krishna Biswas A (2006) Decline in ascorbate peroxidase activity ­ A prerequisite factor for tepal senescence in gladiolus. Journal of Plant Physiology 163, 186-194 Kleber-Janke T, Krupinska K (1997) Isolation of cDNA clones for genes showing enhanced expression in barley leaves during dark-induced senescence as well as during senescence under field conditions. Planta 203, 332-340 Li J, Dai X, Zhao Y (2006) A role for Auxin Response Factor 19 in auxin and ethylene signaling in Arabidopsis. Plant Physiology 140, 899-908 Rosenvasser S, Mayak S, Friedman H (2006) Increase in reactive oxygen species (ROS) and in senescence-associated gene transcript (SAG) levels during dark-induced senescence of Pelargonium cuttings, and the effect of gibberellic acid. Plant Science 170, 873-879 Yoshida S (2003) Molecular regulation of leaf senescence. Current Opinion in Plant Biology 6, 79-84

Space Tagetes patula, an ornamental plant was successfully grown on lunar rock anorthosite as a substrate (Kozyrovska et al. 2006). Plants further flowered in vitro on this space-deried substrate, making this a unique study for the establishment of pioneer plants on a lunar base. Very futuristic viewpoints on space research, lighting for space systems, field test results on hundreds of plants species that have just returned (2005) from space missions as well as the physiology of plants in space have been dealt with in Volume IV of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issue.

Kozyrovska NO, Lutvynenko TL, Korniichuk OS, Kovalchuk MV, Voznyuk TM, Kononuchenko O, Zaetz I, Rogutskyy IS, Mytrokhyn OV, Mashkovska SP, Foing BH, Kordyum VA (2006) Growing pioneer plants for a lunar base. Advances in Space Research 37, 93-99

Stress-resistance/tolerance Molecular studies on salt-tolerance in plants have mainly focused on annuals or perennials, such as Arabidopsis thaliana, Mesembryanthemum crystallinum, or Oryza sativa. Trees, many of which have high stress resistance have not been so well studied. However, Wang et al. (2006) used expressed sequence tags (ESTs) ­ a useful technique to identify genes involved in specific biological functions ­ to discover genes involved in stress tolerance in Tamarix androssowii. Tamarix spp., usually small shrubs or trees ­ ranging from useful ornamentals (e.g. T. chinensis) to invasive plants ­ are commonly found in drought and saline land in Central Asia and China, hence their English comon name, salt cedar. T. androssowii in particular grows well in soda soil and demonstrates strong resistance to abiotic stresses such as high temperature, salt, and drought stresses. ESTs have also been used to identify salinity stress-induced gene expression patterns in Avicennia marina (Mehta et al. 2005), M. crystallinum (Kore-eda et al. 2004), Suaeda salsa (Zhang et al. 2001), and Thellungiella halophila (Wang et al. 2004). Thellungiella, an A. thaliana-related halophyte, is an emerging model species for studies designed to elucidate molecular mechanisms of abiotic stress tolerance. A cDNA microarray containing 3,628 unique sequences derived from

previously described libraries of stress-induced cDNAs in T. salsuginea were used to obtain transcript profiles of its response to cold, salinity, simulated drought, and rewatering after simulated drought (Wong et al. 2004). Several aspects of salinity resistance have been covered in Volume 57(5) of the Journal of Experimental Botany while Umezawa et al. (2006) provide a succinct review of drought resistance through genetic engineering. Transgenic tobacco plants expressing the three halotolerant and halophilic bacterial (Marinococcus halophilus) ectoine genes (viz. ect B, ect A and ect C which code for l-2,4-diaminobutyric acid aminotransferase, l-2,4-diaminobutyric acid acetyl transferase and l-ectoine synthase, respectively) resulted in increased resistance to light and heat stress (Rai et al. 2006). Since Rubisco is susceptibly targeted during abiotic stresses, therefore negatively affecting photosynthesis, there is great interest in selectively targeting the chloroplast (Bock and Khan 2004, Prasad and Saradhi 2004), where ectoine accumulates. Ectoine, as well as its hydroxy derivative, have been shown to protect and stabilize enzymes, proteins, membranes and whole cells against exposure to salt, heating, freezing and desiccation (Arora et al. 2004). Arabidopsis thaliana transgenic plants expressing the Yeast cadmium factor 1 (YCF1), which sequesters glutathione-chelates of heavy metals (Cd(II), As(III) and Sb(II)) and xenobiotics into vacuoles, showed enhanced salt or xenobiotic chemical (1-chloro-2, 4-dinitrobenzene, CDNB) tolerance (Koh et al. 2006). Juniperus oxycedrus plants inoculated with three strains of exotic AM fungi (Glomus intraradices, G. deserticola and G. mosseae) as well as plants grown with composted sewage sludge (SS) developed mechanisms to avoid oxidative damage produced under water-shortage conditions (Alguacil et al. 2006). Both the inoculation with exotic AM fungi and the addition of composted SS significantly stimulated growth and the N and P contents in Juniperus shoot tissues more than plants neither inoculated nor treated with composted SS (well-watered or drought-stressed). Tomato plants cv. `Pusa Ruby'were transformed (Agrobacterium tumefaciens-mediated) with a novel 66 kDa boiling stable protein (BSP) that was highly expressed in Populus tremula in response to gradual water stress (Roy et al. 2006). BSPs play a role in desiccation tolerance against water stress by protecting proteins in membranes and the cytosol. Some BSPs, the dehydrins, are highly hydrophobic and remain stable after boiling. Cao et al. (2006) show how the Arabidopsis GIGANTEA (GI) gene is involved in the regulation of the oxidative stress response; enhanced tolerance of the gi-3 mutant to oxidative stress is associated, at least in part, with constitutive activation of superoxide dismutase (SOD) and ascorbate peroxidase (APX) genes. Recent advances in the regulatory components of ABA-dependent stress-responsive gene expression are summarized in a review by Kim (2006). Peroxiredoxins (Prxs) have diverse functions in cellular defense-signaling pathways. These roles have been reviewed by Jang et al. (2006). Soluble sugars, too, particularly sucrose, glucose, and fructose, have a central role in plant structure and metabolism at the cellular and whole-organism levels. These

aspects in relation to the role of these sugars in stress and signaling have been reviewed by Couée et al. (2006) and by Penna et al. (2006). Gonzali et al. (2006) studied the effects of sucrose at a genome-wide level in dark-grown 4-day-old Arabidopsis thaliana seedlings, identifying 797 genes strongly responsive to sucrose. van Hulten et al. (2006) compared the costs and benefits of priming (chemically achieved by adding low doses of -aminobutyric acid) to those of induced direct defense in Arabidopsis. Ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid) is a common compatible solute in halophilic bacteria. Ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid) biosynthetic genes (ect. ABC) from Halomonas elongata were introduced to tobacco plants using an Agrobacterium-mediated transformation (Moghaieb et al. 2006). The concentration of ectoine under salt-stress conditions was higher in the roots than in leaves and thus ectoine improved the maintenance of root function so that water is taken up consistently and supplied to shoots under saline conditions. Ectoine also enhanced the nitrogen supply to leaves by increasing transpiration and by protecting Rubisco proteins from deleterious effects of salt, thereby improving the rate of photosynthesis. Achard et al. (2006) stress the importance of DELLA proteins in flexible and appropriate modulation of plant growth in response to changes in natural environments. In A. thaliana there are 13 well-conserved plasma membrane aquaporins (plasma membrane intrinsic proteins or PIPs). To cope with rapid changes in the availability of water plants regulate all aquaporins that lie within the plasma membrane. Light has been shed by Törnroth-Horsefield et al. (2006) on the molecular mechanism of aquaporin gating. Mechanosensitive (MS) ion channels provide a mechanism for the perception of mechanical stimuli such as sound, touch, and osmotic pressure. Bochu Wang has done some remarkable developmental experiments on chrysanthemum and gerbera following sound-induced stress (reviewed in FOPB) and finally the molecular mechanisms are beginning to be elucidated. Haswell and Meyerowitz (2006) characterized two MscS (bacterial MS ion channel)-like (MSL) proteins from Arabidopsis thaliana, MSL2 and MSL3. MSL3 can rescue the osmotic-shock sensitivity of a bacterial mutant lacking MS-ion-channel activity, suggesting that it functions as a mechanosensitive ion channel. The authors believe that MSL2 and MSL3 control plastid size, shape, and perhaps division during normal plant development by altering ion flux in response to changes in membrane tension. Franco et al. (2006) discuss the importance of selection of ornamentals in landscaping and xerogardening projects in semi-arid conditions. Some of the pre-conditioning techniques authors suggest to produce high-quality seedlings are: deficit irrigation; using large-sized containers and appropriate substrates, withholding N nutrition, inoculating arbuscular mycorrhizal fungi, applying plant growth retardants and mechanical conditioning methods (including brushing, and shoot- and/or root-pruning).

Achard P, Cheng H, De Grauwe L, Decat J, Schoutteten H, Moritz T, Van Der Straeten D, Peng J, Harberd NP (2006) Integration of plant responses to environmentally activated phytohormonal signals. Science 311, 91-94

Alguacil M, Caravaca F, Díaz-Vivancos P, Hernández JA, Roldán A (2006) Effect of arbuscular mycorrhizae and induced drought stress on antioxidant enzyme and nitrate reductase activities in Juniperus oxycedrus L. grown in a composted sewage sludge-amended semi-arid soil. Plant and Soil 279, 209-218 Arora A, Ha C, Park CB (2004) Inhibition of insulin amyloid formation by small stress molecules. FEBS Letters 564, 121-125 Bock R, Khan MS (2004) Taming plastids for a green future. Trends in Biotechnology 22, 311-318 Cao S, Jiang S, Zhang R (2006) The role of GIGANTEA gene in mediating the oxidative stress response and in Arabidopsis. Plant Growth Regulation 48, 261-270 Couée I, Sulmon C, Gouesbet G, Abdelhak EA (2006) Involvement of soluble sugars in reactive oxygen species balance and responses to oxidative stress in plants. Journal of Experimental Botany 57, 449-459 Franco JA, Martínez-Sánchez JJ, Fernández JA, Bañón S (2006) Selection and nursery production of ornamental plants for landscaping and xerogardening in semi-arid environments. The Journal of Horticultural Science and Biotechnology 81, 2-17 Gonzali S, Loreti E, Solfanelli C, Novi G, Alpi A, Perata P (2006) Identification of sugar-modulated genes and evidence for in vivo sugar sensing in Arabidopsis. Journal of Plant Research 119, 115-123 Haswell ES, Meyerowitz EM (2006) MscS-like Proteins Control Plastid Size and Shape in Arabidopsis thaliana. Current Biology 16, 1-11 Jang HH, Chi Y-H, Park S-K, Lee S-S, Lee J-R, Park J-H, Moon J-C, Lee Y-M, Kim S-Y, Lee K-O, Lee S-Y (2006) Structural and functional regulation of eukaryotic 2-Cys peroxiredoxins including the plant ones in cellular defense-signaling mechanisms against oxidative stress. Physiologia Plantarum 126, 660-701 Kim SY (2006) The role of ABF family bZIP class transcription factors in stress response. Physiologia Plantarum 126, 519-527 Koh E-J, Song W-Y, Lee Y, Kim K-H, Kim K, Chung N, Lee K-W, Hong S-W, Lee H (2006) Expression of yeast cadmium factor 1 (YCF1) confers salt tolerance to Arabidopsis thaliana. Plant Science 170, 534-541 Kore-eda S, Cushman MA, Akselrod I, Bufford D, Fredrickson M, Clark E, Cushman JC (2004) Transcript profiling of salinity stress responses by large-scale expressed sequence tag analysis in Mesembryanthemum crystallinum, Gene 341, 83-92 Mehta PA, Sivaprakash K, Parani M, Venkataraman G, Parida AK (2005) Generation and analysis of expressed sequence tags from the salt-tolerant mangrove species Avicennia marina (Forsk) Vierh. Theoretical and Applied Genetics 110, 416-424 Moghaieb REA, Tanaka N, Saneoka H, Murooka Y, Ono H, Morikawa H, Nakamura A, Nguyen NT, Suwa R, Fujita K (2006) Characterization of salt tolerance in ectoine-transformed tobacco plants (Nicotiana tabaccum): photosynthesis, osmotic adjustment, and nitrogen partitioning. Plant, Cell and Environment 29, 173-182 Penna S, Teixeira da Silva JA, Anant BV (2006) Plant abiotic stress, sugars and transgenics: a perspective. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol III, Global Science Books, Ltd, UK, pp 86-93 Prasad KVSK, Saradhi PP (2004) Enhanced tolerance to photoinhibition in transgenic plants through targeting of glycinebetaine biosynthesis into the chloroplasts. Plant Science 166, 1197-1212 Rai M, Pal M, Sumesh KV, Jain V, Sankaranarayanan A (2006) Engineering for biosynthesis of ectoine (2-methyl 4-carboxy tetrahydro pyrimidine) in tobacco chloroplasts leads to accumulation of ectoine and enhanced salinity tolerance. Plant Science 170, 291-306 Roy R, Purty RS, Agrawal V, Gupta SC (2006) Transformation of tomato cultivar `Pusa Ruby' with bspA gene from Populus tremula for drought tolerance. Plant Cell, Tissue and Organ Culture 84, 49-55 Törnroth-Horsefield S, Wang Y, Hedfalk K, Johanson U, Karlsson M, Tajkhorshid E, Neutze R, Kjellbom P (2006) Structural mechanism of plant aquaporin gating. Nature 439, 688-694 Umezawa T, Fujita M, Fujita Y, Yamaguchi-Shinozaki K, Shinozaki K (2006) Engineering drought tolerance in plants: discovering and tailoring genes to unlock the future. Current Opinion in Biotechnology 17, 113-122 van Hulten M, Pelser M, van Loon LC, Pieterse CMJ, Ton J (2006) Costs and benefits of priming for defense in Arabidopsis. Proceedings of the National Academy of Sciences USA 103, 5602-5607 Wang ZL, Li PH, Fredricksen M, Gong ZZ, Kim CS, Zhang CQ, Bohnert HJ, Zhu JK, Bressan RA, Hasegawa PM, Zhao YX, Zhang H (2004), Expressed sequence tags from Thellungiella halophila, a new model to study plant salt-tolerance. Plant Science 166, 609-616 Wong CE, Li Y, Labbe A, Guevara D, Nuin P, Whitty B, Diaz C, Golding GB, Gray GR, Weretilnyk EA, Griffith M, Moffatt BA (2006) Transcriptional profiling implicates novel interactions between abiotic stress and hormonal responses in Thellungiella, a close relative of Arabidopsis. Plant Physiology 140, 1437-1450 Wang Y-C, Yang C-P, Liu G-F, Jiang J, Wu J-H (2006) Generation and analysis of expressed sequence tags from a cDNA library of Tamarix androssowii. Plant Science 170, 28-36 Zhang L, Ma X-L, Zhang Q, Ma C-L, Wang P-P, Sun Y-F, Zhao Y-X , Zhang H (2001) Expressed sequence tags from a NaCl-treated Suaeda Salsa cDNA library. Gene 267, 93-200

Tissue culture and in vitro micropropagation LEAFY COTYLEDON2 (LEC2) is a B3 domain protein required for several aspects of embryogenesis, including the

maturation phase, and is sufficient to induce somatic embryo development in vegetative cells; LEC genes are reviewed by Baumbusch (2006). Braybrook et al. (2006) demonstrate that LEC2 directly controls a transcriptional program involved in the maturation phase of seed development. Eckardt briefly reviews the genetic and epigenetic regulation of embryogenesis. Jain and Babbar (2006) could successfully apply xanthan gum, a microbial desiccation-resistant polysaccharide prepared commercially by aerobic submerged fermentation from Xanthomonas campestris, as a solidifying agent in the successful plant tissue culture of several plants. Other than economic advantages, its use in the in vitro seed germination, caulogenesis and rhizogenesis of Albizzia lebbeck, androgenesis in anther cultures of Datura innoxia, and somatic embryogenesis in callus cultures of Calliandra tweedii were shown to be clearly comparable to conventional agar-based media. Lychnis senno, a rare and valued ornamental plant, could be successfully propagated in vitro when seedling nodal segments were cultured on full MS with 0.5 mg/l BA and 0.05 mg/l NAA (Chen et al. 2006). A high percentage of rooting (91.7%) could be induced on half-strength MS medium with 0.5 mg/l NAA. Iris pumila leaf base culture on MS with 4.5 M each of 2,4-D and Kin resulterd in optimal somatic embryogenesis (Jevremovi and Radojevi 2006). Medium with BAP (4.5 M) or BAP + zeatin (4.5 and 0.2 M, respectively) also gave rise to somatic embryogenesis. Further discussion about I. pumila in vitro culture may be found in Jevremovi (2006). Still related to Iris, floral form may be explained by the 17 different pollination systems that exist in the genera of sub-Saharan African Iridaceae in which recurrent shifts in pollination system have evolved in those with ten or more species (Goldblatt and Manning 2006). Hazarika (2006) and Hazarika et al. (2006) reviewed the morphological and physiological disorders associated with the in vitro culture of plants and their subsequent effective acclimatization. Apogamy is the generation of a sporophyte from somatic gametophyte cells, i.e. without the intervention of sexual organs. It is estimated that ~10% of ferns and several Pteridophyta show "obligate apogamy" life cycles in which a sporophyte is regularly produced from gametophyte without sexual fusion. Dryopteris affinis sp. affinis, a diploid fern with an apomictic life cycle, was used to study the effect of exogenously-applied phytohormones to study the formation of an apogamous embryo in the gametophyte (Menéndez et al. 2006). NAA or GA3 promoted apogamy. Hypoxis hemerocallidea, a tuberous perennial herb with long, strap-shaped leaves and yellow, star-shaped flowers, is primarily a component of grasslands but has a very wide geographical distribution in Mozambique (grasslands, savannahs, wet forests). H. hemerocallidea,like several other Hypoxis spp. is an attractive ornamental, serving well as a miniature pot-plant, while also having important medicinal properties. It is at present a highly endangered species. Ndong et al. (2006) recognizing this importance, were successful in finding a direct multiple shoot formation or shoot organogenenic pathway from corm-derived calluses. Calluses were induced with Kin (3 mg/l) and NAA (1 mg/l). Subsequent shoots were derived from callus indirectly through induction with BA (1.5 mg/l) and NAA (0.5 mg/l). Almost 100% callus and shoot induction were achieved in both steps, respectively.

Carbonic anhydrase is a zinc-containing metalloenzyme that catalyzes the reversible conversion of bicarbonate to CO2. Yanyou et al. (2006), primarily working with kales and other vegetables in vitro, showed how the carbonic anhydrase activities of plants and their growth rates were correlated, concluding that the greater the carbonic anhydrase activity of the plantlet, the higher its net photosynthetic rate, and the faster its growth rate. This study has direct implications for the in vitro growth of ornamentals which still continue to be tissue cultured in poorly ventilated vessels, or for plants that are micropropagated photoautotrophicaly (i.e. additional CO2 added). Callus of Notocactus magnificus, the blue cactus, a highly ornamental species native to Brazil was successfully induced on MS medium supplemented with 2% (w/v) sucrose, 0.5 M 2,4-D, 4.4 M BA, 0.4 mg/l thiamine HCl and 100 mg/l i-inositol (de Medeiros et al. 2006). Callus subsequently transferred to MS medium supplemented with 22.2 M BA, 3% (w/v) sucrose and 0.6% (w/v) agar resulted in high levels of spontaneous shoot formation. The micropropagation of several cacti species, approximately 100 of which are rare and which require urgent conservation approaches, need to be addressed, and this study paves the way for equally successful results in the near future. Zhang et al. (2006) established a rapid and efficient somatic embryogenic system for Syngonium podophyllum `Variegatum', based on petiole and leaf explants when placed on MS medium supplemented 2.5 mg/l TDZ with 0.5 mg/l NAA or 2.0 mg/l TDZ with 0.2 mg/l NAA or with 0.2 and 0.5 mg/l 2,4-D, respectively for one-sided or two-sided somatic embryo formation. Approximately 85% of somatic embryos could be germinated on medium containing 2.0 mg/l BA and 0.2 mg/l NAA, while an estimated 50-150 plantlets per petiole could be regenerated, providing a useful, simple mass production system for Syngonium in vitro. Only young floral apices of Alstroemeria cv.`Yellow King' could produce adventitious shoots by direct organogenesis, and highest shoot formation occurred under the following conditions: incubation in the dark for 15 days at 8°C followed by 15 days at 25°C and a 16-h/8-h light/dark regime; use of ½-strength MS (salt concentration) liquid medium, supplemented with 2.5 mg/l KIN, 1.5 mg/l BA and 1.0 mg/l NAA (Pedraza-Santos et al. 2006). Filter paper was shown to be important. Teixeira da Silva (2003) showed the importance of filter paper in tissue culture, and how the choice of filter paper can influence the outcome of organogenesis, using chrysanthemum and tobacco as model plants. Pischke et al. (2006) conducted a transcriptome-based analysis of a well established habituated Arabidopsis (Arabidopsis thaliana) cell culture line in order to explore genome-wide expression changes underlying the phenomenon of habituation by monitoring the levels of expression of the cytokinin receptor CRE1, as well as altered levels of expression of several other genes involved in cytokinin signaling. Cytokinin habituation was claimed to be achieved by several epigenetic changes. Rosa canina `Inermis', R. indica `Major', R. manetti, and R. multiflora rootstocks were successfully multiplied in vitro by Kucharska et al. (2006). One of their significant findings was that improvement in rooting was obtained using vitamin B2 in

the BAP-containing medium. Kaur et al. (2006) developed a somatic embryogenic pathway for Rosa bourboniana, a scented rose species, by using 15M 2,4-D; 800mgl-1 L-proline was required for secondary metabolism while 5M BAP resulted in somatic embryo germination. See also 3) of the Reviews section below. A rapid and mass scale clonal propagation of Lavendula officinalis from shoot tip explants was devised by Chishti et al. (2006) in which 2.0 mg/l BA in MS medium resulted in greatest shoot multuplication (~45%), and shoots could root on ½MS + 1.0 mg/l IBA. Glocke et al. (2006) micropropagated ornamental Eucalyptus cv. `Urrbrae Gem' via enhanced axillary shoot proliferation using in vitro germinated seedlings on a woody plant medium (WPM) supplemented with 2.2M BAP, 1.0M -NAA, and 1.5M GA3, gelled with 5gl-1 Phytagel®. In vitro regeneration of plants via somatic embryogenesis in Chorispora bungeana, an alpine plant with freeze-tolerance, using cell suspensions initiated from leaf-derived callus was achieved by Wang et al. (2006). Primary calli were induced on MS media supplemented with 4.0mgl-1 GA3, 0.2mgl-1 -NAA and 0.2mgl-1 2,4-D. In an attempt to break bulblet dormancy in vitro ­ thus reducing the need to have such a step prior to planting in soil and therefore allowing for sprouting ­ Jásik and de Klerk (2006) applied methyl jasmonic acid (MeJA) to the headspace of three lilies, Lilium speciosum "Rubrum No. 10," L. longiflorum "Snow Queen," and the Asiatic hybrid "Connecticut King." The treatment was found to be effective for the latter only when bulblets had been regenerated at 300 or 1000 l l-1 MeJA. Lilium in vitro culture has been well-covered and reviewed in several chapters in Volume II of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issue. Still related to bulbous species, the physiological and biochemical mechanisms of shoot elongation after cold period in hyacinth (Hyacinthus orientalis L. cv. Delft Blue) were analyzed by Sato et al. (2006) while Ohyama et al. (2006) provide a detailed study and summary of over 20 years research of these processes in Tulipa bulbs. Sriskandarajah et al. (2006), conducting fundamental analyses on two cacti, Rhipsalidopsis (Easter cactus) and Schlumbergera (Christmas cactus), concluded that the endogenous level of auxins and cytokinins and their respective ratios affected the outcome of in vitro regeneration: an enhanced auxin metabolism (biosynthesis, conjugation/ deconjugation, and peroxidase (POX) activity), in combination with an enhanced cytokinin oxidase/dehydrogenase activity, shifted the auxin and cytokinin pool, favoring adventitious shoot formation in Rhipsalidopsis, whereas the low level of POX activity, together with auxin autotrophy/conjugation, made Schlumbergera more recalcitrant. MS medium containing 1 mg/l 2,4-D and 0.5 mg/l BA was sufficient to induce somatic embryos in St Augustinegrass (Stenotaphrum secundatum), an important warm season turf and pasture grass (Li et al. 2006). For a comprehensive analysis of some of the most significant advances in tissue culture, theoretical development and practical applications, readers are referred to Volume II of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issue.

Baumbusch LO (2006) Genetic control of plant embryogenesis and embryo dormancy in Arabidopsis. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 417-428 Braybrook SA, Stone SL, Park S, Bui AQ, Le BH, Robert L. Fischer, Robert B. Goldberg, and John J. Harada (2006) Genes directly regulated by LEAFY COTYLEDON2 provide insight into the control of embryo maturation and somatic embryogenesis. Proceedings of the National Academy of Sciences USA 103, 3468-3473 Chen L, Wang Y, Xu C, Zhao M, Wu J (2006) In vitro propagation of Lychnis senno Siebold et Zucc., a rare plant with potential ornamental value. Scientia Horticulturae 107, 183-186 Chishti N, Kaloo ZA, Shawl AS, Sultan P (2006) Rapid in vitro clonal propagation of Lavendula officinalis chaix a multipurpose plant of industrial importance. Pakistan Journal of Biological Sciences 9, 514-518 de Medeiros LA, Roberval Cássia Salvador de Ribeiro, Luiz Antônio Gallo, Enio Tiago de Oliveira, Maria Esmeralda Soares Demattê P (2006) In vitro propagation of Notocactus magnificus. Plant Cell, Tissue and Organ Culture 84, 147-151 Eckardt NA (2006) Genetic and epigenetic regulation of embryogenesis. Plant Cell 18, 781-784 Glocke P, Delaporte K, Collins G, Sedgley M (2006) Micropropagation of juvenile tissue of Eucalyptus erythronema×Eucalyptus stricklandii cv. `Urrbrae gem'. In Vitro Cellular and Developmental Biology ­ Plant 42, 139-143 Goldblatt P, Manning JC (2006) Radiation of pollination systems in the Iridaceae of sub-Saharan Africa. Annals of Botany 97, 317-344 Hazarika BN (2006) Morpho-physiological disorders in in vitro culture of plants. Scientia Horticulturae 108, 105-120 Hazarika BN, Teixeira da Silva JA, Talukdar A (2006) Genetic control of plant embryogenesis and embryo dormancy in Arabidopsis. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 427-438 Jain R, Babbar SB (2006) Xanthan gum: an economical substitute for agar in plant tissue culture media. Plant Cell Reports 25, 81-84 Jásik J, de Klerk GJ (2006) Effect of methyl jasmonate on morphology and dormancy development in lily bulblets regenerated in vitro. The Journal of Plant Growth Regulation 25, 45-51 Jevremovi S, Radojevi Lj (2006) Establishment of efficient regeneration protocol from leaf explants of Iris pumila shoots cultured in vitro. Scientia Horticulturae 108, 100-103 Jevremovi S, Suboti A, Radojevi L (2006) In vitro morphogenesis of dwarf irises. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol II, Global Science Books, Ltd, UK, pp 551-557 Kaur N, Pati PK, Sharma M, Ahuja PS (2006) Somatic embryogenesis from immature zygotic embryos of Rosa bourboniana Desp. In Vitro Cellular and Developmental Biology ­ Plant 42, 124-127 Kucharska D, Gruchala A, Orlikowska T (2006) In vitro propagation of four rose rootstocks. Propagation of Ornamental Plants 6, 44-50 Li R, Bruneau AH, Qu R (2006) Improved plant regeneration and in vitro somatic embryogenesis of St Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze]. Plant Breeding 125, 52-56 Menéndez V, Villacorta NF, Revilla MA, Gotor V, Bernard P, Fernández H (2006) Exogenous and endogenous growth regulators on apogamy in Dryopteris affinis (Lowe) Fraser-Jenkins sp. affinis. Plant Cell Reports 25, 85-91 Ndong YA, Wadouachi A, Sangwan-Norreel BS, Sangwan RS (2006) Efficient in vitro regeneration of fertile plants from corm explants of Hypoxis hemerocallidea landrace Gaza ­ The "African Potato". Plant Cell Reports 25, 265-273 Ohyama T, Komiyama S, Ohtake N, Sueyoshi K, Teixeira da Silva JA, Ruamrungsri S (2006) Genetic control of plant embryogenesis and embryo dormancy in Arabidopsis. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol III, Global Science Books, Ltd, UK, pp 12-25 Pedraza-Santos ME, López-Peralta MC, González-Hernández VA, Engleman-Clark EM, Sánchez-García P (2006) In vitro regeneration of Alstroemeria cv. `Yellow King' by direct organogenesis. Plant Cell, Tissue and Organ Culture 84, 169-178 Pischke MS, Huttlin EL, Hegeman AD, Sussman MR (2006) A transcriptome-based characterization of habituation in plant tissue culture. Plant Physiology 140, 1255-1278 Sato A, Okubo H, Saitou K (2006) Increase in the expression of an alpha-amylase gene and sugar accumulation induced during cold period reflects shoot elongation in hyacinth bulbs. Journal of the American Society for Horticultural Science 131, 185-191 Sriskandarajah S (2006) Regenerative capacity of cacti Schlumbergera and Rhipsalidopsis in relation to endogenous phytohormones, cytokinin oxidase/dehydrogenase, and peroxidase activities. The Journal of Plant Growth Regulation 25, 79-88 Teixeira da Silva (2003) Filter paper significantly affects the morphogenic programmes, and buffers the phytotoxic effect of antibiotics in chrysanthemum and tobacco thin cell layer in vitro culture. HortScience 38, 1403-1407 Wang J, An L, Wang R, Yang D, Si J, Fu X, Chang J, Xu S (2006) Plant regeneration of Chorispora bungeana via somatic embryogenesis. In Vitro Cellular and Developmental Biology ­ Plant 42, 148-151 Yanyou W, Li X, Li P, Zhao X (2006) Comparison of carbonic anhydrase activity among various species of plantlets. Plant Cell, Tissue and Organ

Culture 84, 124-127 Zhang Q, Chen J, Henny RJ (2006) Regeneration of Syngonium podophyllum `Variegatum' through direct somatic embryogenesis. Plant Cell, Tissue and Organ Culture 84, 161-168

2) Roque ACA, Lowe CR (2006) Advances and applications of de novo

designed affinity ligands in proteomics. Biotechnology Advances 24, 17-26

Weeds The sarcotoxin IA gene was introduced into tomato plants, and transgenic oplants were co-planted in pots and polyethylene bags with seeds of Orobanche aegyptiaca, a parasitic weed (Radi et al. 2006). In both potting systems most of the parasite tubercles that attached to the transgenic root plants turned necrotic and developed abnormally. Orobanche spp. is an obligatory chlorophyll-lacking root parasite that attacks the roots of economically important crops (Solanaceae, Fabaceae, Compositae and other food and ornamental crops) worldwide, especially around the Mediterranean, in the Middle East and in east Europe causing severe losses in yield and quality. Sarcotoxin IA is a 63-residue peptide, and is one of four cecropin-type proteins encoded by the sarcotoxin I gene cluster in the flesh fly, Sarcophaga peregrine. The primary target of this toxin is possibly the microbial membrane, and its antimicrobial (bacterial and fungal) effect is probably due to ionophore activity. Although very preliminary results, uses of sugarcane straw leachate (composed primarily of vanillic, syringic and ferulic acids) could either stimulate or inhibit root growth, depending on the concentration and on the species (Sampietro and Vattuone 2006). Mainly cereals and vegetable crops were tested, as were some of their weed plants. This bodes well as an alternative herbicide in which a crop grown would show differential sensitivity ot the sugarcane straw leachate.

Radi A, Dina P, Guy A (2006) Expression of sarcotoxin IA gene via a root-specific tob promoter enhanced host resistance against parasitic weeds in tomato plants. Plant Cell Reports 25, 297-303 Sampietro DA, Vattuone MA (2006) Sugarcane straw and its phytochemicals as growth regulators of weed and crop plants. Plant Growth Regulation 84, 21-27

The advantages of affinity chromatography for proteomic analyses is highlighted, specifically the strengths of synthetic de novo designed ligands rather than biological ligands for the chromatography-based purification of biomolecules. The importance of proteomics in Arabidopsis research is reviewed by Baginsky and Gruissem (2006). In addition, several authors discuss important points of plant proteomics in an excellent compilation of articles in Volume 57, Issue 7 of the Journal of Experimental Botany. A new plastid proteome database to provide information about the proteomes of chloroplasts, etioplasts and undifferentiated plastids has been described by Kleffmann et al. (2006) and may be accessed at: http://www.plprot.ethz.ch. Dunkley et al. (2006) used the localization of organelle proteins by the isotope tagging technique in conjunction with isotope tags for relative and absolute quantitation and 2D liquid chromatography for the simultaneous assignment of proteins to multiple subcellular compartments, and, by using this approach, the density gradient distributions of 689 proteins from A. thaliana were determined, enabling confident and simultaneous localization of 527 proteins to the endoplasmic reticulum, Golgi apparatus, vacuolar membrane, plasma membrane, or mitochondria and plastids.

Baginsky S, Gruissem W (2006) Arabidopsis thaliana proteomics: from proteome to genome. Journal of Experimental Botany 57, 1485-1491 Dunkley TPJ, Hester S, Shadforth IP, Runions J, Weimar T, Hanton SL, Griffin JL, Bessant C, Brandizzi F, Hawes C, Watson RB, Dupree P, Lilley KS (2006) Mapping the Arabidopsis organelle proteome. Proceedings of the National Academy of Sciences USA 103, 6518-6523

3) Pati PK, Rath SP, Sharma M, Sood A, Ahuja PS (2006) In vitro

propagation of rose - a review. Biotechnology Advances 24, 94-114

Reviews (January 2006 ­ April 2006)

by Jaime A. Teixeira da Silva

This section brings to light important reviews on several topics. Should any review have been missed that you feel should be included in GPL, kindly send information and requests to [email protected] for possible inclusion in a forthcoming Issue.

The in vitro propagation of rose is highlighted. Certain important and vastly different results have also been reported by Khosh-Khui and Teixeira da Silva (2006). Moss roses are old garden roses covered with a mossy growth on flower pedicel and calyx. The moss releases a pine-scented oleoresin that is very sticky and odoriferous. Rosa x centifolia `muscosa' was the first moss rose to be obtained by bud-mutation but, interestingly, R. x damascena `Quatre Saisons Blanc Mousseux' was the first repeat-blooming cultivar, thus interesting breeders. In a study by Caissard et al. (2006), the anatomy of these sports (i.e. bud-mutations) is characterized and the volatile organic compounds produced by the moss versus the petals are identified. They are compared between the two lines and their respective parents.

Caissard J-C, Bergougnoux V, Martin M, Mauriat M, Baudino S (2006) Chemical and histochemical analysis of `Quatre Saisons Blanc Mousseux', a moss rose of the Rosa x damascena group. Annals of Botany 97, 231-238 Khosh-Khui M, Teixeira da Silva JA (2006) In vitro culture of Rosa species. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol III, Global Science Books, Ltd, UK, pp 514-526

1) Liu Y, Yang H, Sakanishi A (2006) Ultrasound: Mechanical gene transfer

into plant cells by sonoporation. Biotechnology Advances 24, 1-16

Ultrasound has been shown to produce induce cell death or transient membrane permeabilization (sonoporation) via acoustic cavitation. The use of ultrasound, especially sonication-assisted Agrobacterium-mediated transformation (SAAT) for the genetic transformation of plant cells and tissues is reviewed. Recently, SAAT was successfully applied to genetically transform Nicotiana tabacum with higher transgenic production rates than conventional Agrobacterium-mediated transofrmation, or biolistics (Teixeira da Silva 2005).

Teixeira da Silva JA (2005) Simple multiplication and effective genetic transformation (four methods) of in vitro-grown tobacco by stem thin cell layers. Plant Science 169, 1046-1058

4) de Carvalho CCCR, da Fonseca MMR (2006) Biotransformation of

terpenes. Biotechnology Advances 24, 134-142

Terpenes, which occur widely in nature, have an important ecological role in acting as deterrents against feeding by herbivores, as antifungal defenses and attractants for pollinators. Moreover several terpenoids and their oxygenated derivatives are used in the fragrance and flovour industry. The use of plants,

among other organisms, to biotransform terpenes in bioreactors is discussed. This review also updates developments in biotransformation catalysts, reaction media, reactor types and biokinetic resolution of terpenes. 5) Canton DA, Litchfield DW (2006) The shape of things to come: An

emerging role for protein kinase CK2 in the regulation of cell morphology and the cytoskeleton. Cellular Signalling 18, 267-275

9) Cowan AK (2006) Phospholipids as plant growth regulators. Plant

Growth Regulation 48, 97-109

Phospholipase A (PLA), C (PLC) and D (PLD), lysophospholipids, and phosphatidic acid (PA) are key components of plant lipid signalling pathways. Cowan shows the application of PLs to plant growth. 10) Kuchar M (2006) Plant telomere-binding proteins. Biologia Plantarum

50, 1-7

Cell growth and differentiation are controlled by the reversible phosphorylation of proteins that is mediated by a complex network of protein kinases, one component of which is protein kinase CK2. In this review, the implication of CK2 in several cellular processes (e.g. cell cycle regulation, circadian rhythms, apoptosis, transformation and tumorigenesis) is discussed. Circadian rhythms are also reviewed by McClung (2006).

McClung CR (2006) Plant circadian rhythms. Plant Cell 18, 792-803

In comparison to mammalian systems, relatively little is known about plant telomeres. In this review, the building blocks of telomere structure, the telomere-binding proteins, are discussed in terms of their central importance to telomere metabolism. 11) A series of papers detailing the latest developments in nutriomics and biofortification is available in Physiologia Plantarum 126, Issue 3. Dominique van der Straeten also summarizes developments in Volume IV of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issue. The use of transgenic Arabidopsis seeds to produce insulin, to deal with an increase in diabetes cases, accounted for 0.13% of total seed protein (Nykiforuk et al. 2006). Seeds as bioreactors have been reviewed by Li and Jiang in Volume II of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issue.

Nykiforuk CL, Boothe JG, Murray EW, Keon RG, Goren HJ, Markley NA, Moloney MM (2006) Transgenic expression and recovery of biologically active recombinant human insulin from Arabidopsis thaliana seeds. Plant Biotechnology Journal 4, 77-85

6) Bautista-Baños S, Hernández-Lauzardo AN, Velázquez-del Valle MG,

Hernández-López M, Ait Barka E, Bosquez-Molina E, Wilson CL (2006) Chitosan as a potential natural compound to control pre and postharvest diseases of horticultural commodities. Crop Protection 25, 108-118

Chitosan is a high molecular polymer, nontoxic, bioactive agent with fungicidal effects and elicitation of defence mechanisms in plant tissues (Terry and Joyce 2004). The use of chitosan, obtained from the outer shell of crustaceans such as crabs, krills and shrimps, is often applied directly to soil or to fresh produce to control bacteria and fungi in pre- and post-harvest cultures; it appears as if the use of chitosan has not been extensively applied yet to ornamental commodities, but its success with other horticultural produce suggest a positive future for the applied use in floriculture and ornamental in vitro and greenhouse cultures, cut flowers and foliage.

Terry LA, Joyce DC (2004) Elicitors of induced disease resistance in postharvest horticultural crops: a brief review. Postharvest Biology and Technology 32, 1-13

12) Kim G-T, Cho K-H (2006) Recent advances in the genetic regulation of

the shape of simple leaves. Physiologia Plantarum 126, 494-502

7) Prosser JI, Rangel-Castro JI, Killham K (2006) Studying

plant­microbe interactions using stable isotope technologies. Current Opinion in Biotechnology 17, 98-102

The plant-microbe interaction in the rhizosphere can be simplistically summarized in two sentences: the plant exerts a major influence on microbial communities through the release of a range of organic compounds, as root exudates, and eventually through nutrients released when the roots die and are degraded. IN return, plants benefit from the microbial turnover of root exudates and other soil organic and inorganic matter, which releases nutrients and enhances the soil structure. The use of stable isotope probing or SIP allows the scientist to determine the origin and fate of mediating organic compounds, and these themes are explored in this review. 8) Bhalla PL, Singh MB (2006) Molecular control of stem cell maintenance

in shoot apical meristem (2006) Plant Cell Reports 25, 249-256

The early control of leaf shape and size depends on the control of the rate and plane of cell division at the shoot apical meristem and the polarity-dependent cell differentiation in the leaf primordium. The genetic regulation of leaf shape in the model plant Arabidopsis thaliana from the perspective of spatial and temporal balance among cell proliferation, enlargement, and differentiation are highlighted, while a historical perspective of the genetic factors affecting simple leaf development and form are discussed. Cookson and Granier (2006) further studied shade-induced dynamic changes in leaf development from the level of the whole rosette to the cellular level.

Cookson SJ, Granier C (2006) A dynamic analysis of the shade-induced plasticity in Arabidopsis thaliana rosette leaf development reveals new components of the shade-adaptative response. Annals of Botany 97, 443-452

13) Choi D, Cho H-T, Lee Y (2006) Expansins: expanding importance in

plant growth and development. Physiologia Plantarum 126, 511-518

Pluripotent stem cells in the shoot apical meristems (SAMs) sustain post-embryonic organ initiation and development in plants as a result of the coordination in their formation and differentiation, related to transcriptional regulation and intercellular signalling. The molecular regulation of stem cell maintenance and renewal in the SAM and molecular approaches for deciphering these processes are discussed.

Expansins play several roles in plant growth and development, such as cell wall extension, fruit softening, abscission, floral organ development, symbiosis, and the response to environmental stresses. These roles are all reviewed with an emphasis on transgenic plants to demonstrate these roles. 14) Ziv M, Naor V (2006) Flowering of geophytes in vitro. Propagation of

Ornamental Plants 6, 3-16

The impact of in vitro conditions on shortening the juvenile period in geophytes is discussed. Although the discussion is limited to geophytes, it serves an important basis for the

potential advancement of geophytes in the ornamental, food, medicinal, and craft industries. Wider and deeper reviews, and practical applications of in vitro flowering for "in vitro bouquets" are discussed by Sudhakaran et al. and Fennel et al. (2006) in Volumes II and IV of Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issue, respectively. 15) Feng C-P, Mundy J (2006) Gene discovery and functional analyses in

the model plant Arabidopsis. Journal of Integrative Plant Biology 48, 5-14

20) Forest vegetation management is broadly reviewed in Forestry 79(1). 21) Hall RD (2006) Plant metabolomics: from holistic hope, to hype, to hot

topic. New Phytologist 169, 453-468

Transposon and T-DNA insertions, TILLING, Deleteagene, and RNA interference to functionally analyze genes of interest in Arabidopsis research are reviewed. TILLING (for Targeting Local Lesions IN Genomes) is a technique that allows for searches in the genomes of mutagenized organisms for mutations in a chosen gene, typically single base-pair substitutions, and has also been reviewed by Haughn and Gilchrist (2006) and Comai and Henikoff (2006).

Comai L, Henikoff S (2006) TILLING: practical single-nucleotide mutation discovery. The Plant Journal 45, 684-694 Haughn GW, Gilchrist EJ (2006) Tilling in the botanical garden: a reverse genetic technique suitable for all plant species. In: Teixeira da Silva JA (ed) Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues (1st ed) vol I, Global Science Books, Ltd, UK, pp 476-482

Newly designed, dedicated statistical, bioinformatics and data mining strategies all prvide insights into how plants are organized and how metabolism is both controlled but highly flexible. The importance of metabolomics is highlighted in this review. 22) An outstanding collection of review articles in Current Opinion in series of journals while reviews on cellular events is well covered in Trends in Cell Biology.

Open your eyes!

by Jaime A. Teixeira da Silva

In this section I wish to create a brief awareness of certain issues in the (plant) biotechnology world that should lead us to be more conscious of our research activities. Could plants live forever? In a fascinating article in the March Issue of Scientific American, the authors Sinclair and Guarente (2006) note how a series of recently discovered genes, known by cryptic names as daf-2, pit-1, amp-1, clk-1 and p66Shc, have been found to affect stress resistance and life span in laboratory organisms, suggesting that they could be part of a fundamental mechanism for surviving adversity. The authors themselves focussed on a gene called SIR2, variants of which are present in all organisms studied so far, from yeast to humans. No mention is made of plants. What is so fascinating about this article is that when an extra copy of the SIR2 gene was added to a yeast cell, the formation of rDNA circles (aging in mother cells was caused by some form of rDNA instability that was mitigated by the Sir proteins) was repressed and the cell's life span was extended by 30%. That finding explained how sir2 could act as a longevity gene in yeast, but amazingly, they soon discovered that extra copies of the sir2 gene also extended the life span of roundworms by as much as 50%. Sirtuins are known to modify tubulin, and may affect cell division and longevity. It would be of absolute interest to ornamental scientists and plant scientists in general to see if a SIR2 homologue exists in plants, and if cloned into a plant would result in increased field life or even, in the case of cut flowers, increased vase life. Patenting plant life One of the irrefutable facts about the advance of science is the hand-in-hand issue of legalities and ethics associated with methodology and use of results. In a survey reported in the February issue of Scientific American by Gary Stix, it was claimed that by mid-2005 almost 20% of the entire human genome (approx. 24,000 genes) had already been patented by corporations, universities, government agencies and nonprofit groups. Incyte alone owned nearly 10% of all human genes. The report goes further in saying that biomedical research as yet has not been disrupted, but that the deluge may still be on its way. In that sense plant science is "lucky", with the Arabidopsis and rice

16) Hu Z-B, Du M (2006) Hairy root and its application in plant genetic

engineering. Journal of Integrative Plant Biology 48, 121-127

It is now common practice to use hairy root cultures ­ transformed plant parts with Agrobacterium rhizogenes ­ as an efficient means of producing secondary metabolites; they are characterized by a high growth rate and genetic stability. This review looks at how these cultures have turned out to be a valuable tool with which to study the biochemical properties and the gene expression profile of metabolic pathways. 17) Nitric oxide (NO) plays several extremely important roles in plant growth and development. NO and NO signalling have been covered in several good reviews in the Journal of Experimental Botany 57(3). The importance of nitric oxide (NO) and hydrogen peroxide (H2O2) as key signalling molecules produced in response to various stimuli and involved in a diverse range of plant signal transduction processes, including development, stress and pathogenesis have been reviewed by Bright et al. (2006).

Bright J, Desikan R, Hancock JT, Weir IS, Neill SJ (2006) ABA-induced NO generation and stomatal closure in Arabidopsis are dependent on H2O2 synthesis. The Plant Journal 45, 113-122

18) Phenotypic plasticity in cyanobacteria, whole plants, leaves, photosynthesis, and roots has been reviewed in a collection of articles in the Journal of Experimental Botany 57(2). 19) Grant-Downton RT, Dickinson HG (2006) Epigenetics and its

implications for plant biology 2. The `epigenetic epiphany': epigenetics, evolution and beyond. Annals of Botany 97, 11-27

In this review, the patterns of epigenetic variation, which may be informative in taxonomy and systematics, as well as population biology and conservation, are highlighted. Furthermore the role of epigenetic systems in transducing environmental signals to altering gene expression, genomic architecture and defence are boldened.

genome projects only recently having reached completion, and the time lag behind the human science field may allow us to reflect on the stance that we need to take with respect to patenting plant life, in specific plant genes. Although this issue has not been openly discussed, I encourage open and constructive discussion in this area in order to guage the importance of getting a balance between biotechnology, law, and ethics. Paradise and Janson (2006) state "While debate continues as to whether genetic sequences, which many argue represent natural phenomena rather than inventions, should be subject to standard patent protections, issuance of patents that claim DNA sequences remains common practice. In an attempt to insulate researchers from patent claims that could hinder scientific progress, many countries have provided general exemptions for scientific research. However, there is no international consensus about the extent of required protections, and even existing exemptions vary widely in clarity and are limited in practical application. We believe that gene patents raise several unique issues that are inadequately handled by the current research exemptions." A patent thicket is a phenomenon whereby overlapping patents in the field of genetics will create a costly and legally complex situation. Verbeure et al. (2006) suggest a means by which this can be avoided by creating a "patent pool" whose rationale and dynamics are discussed in more detail. It is time for us as plant scientists to reflect further...

Paradise J, Janson C (2006) Decoding the research exemption. Nature Reviews Genetics 7, 148-154 Verbeure B, van Zimmeren E, Matthijs G, Van Overwalle G (2006) Patent pools and diagnostic testing. Trends in Biotechnology 24, 115-120

Meetings and Events (June ­ December)

MAY 'RNAi-2006-Boston' Meeting. May 1-3, 2006, Waltham, MA, USA. http://www.expressgenes.com/ 27th Symposium on Biotechnology for Fuels and Chemicals. May 1-4, 2006, Denver, Colorado, USA. http://www1.eere.energy.gov/biomass/biotech%5Fsymposium/ International workshop on crop and forage production using saline waters in dry areas. May 7-10, 2006, Birjand, Iran. http://www.namstct.org/ I International Symposium on Fresh Food Quality Standards: Better Food by Quality and Assurance. May 7-11, 2006, Amman, Jordan. www.ncartt.gov.jo Biotech & Finance Forum. May 8, 2006, Munich, Germany. www.e-unlimited.com/bff Conference on date palm production and processing technology. May 9-11, 2006, Muscat, Oman, http://www.squ.edu.om/agr/depts/do/conference/conf-int-dpppt.html Workshop on reducing emissions from deforestation. May 10-12, 2006, Bad Blumau, Austria. http://www.joanneum.at/REDD/ International Pharmaceutical Industry Conference. May 14-17, 2006, Edinburgh, UK. http://www.soci.org/SCI/SCIpharm/html/home.jsp ACHEMA 2006 (28th International Exhibition-Congress on Chemical Engineering, Environmental Protection and Biotechnology). May 15-19, 2006, Frankfurt am Main, Germany, www.achema.de Biosafety II: Practical course in evaluation. May 15-19, 2006, Florence, Italy. http://www.icgeb.trieste.it/MEETINGS/CRS06/15_19maggio.pdf European Venture Market Berlin 2006. May 16-18, 2006, BerlinAdlershof, FR Germany. http://www.europeanventuremarket.com/ First COSTECH scientific and technological conference. May 17-19, 2006, Tanzania. http://www.costech.or.tz/technological_conference.htm The Cell Cycle. May 17-21, 2006, Cold Spring Harbor, New York. http://meetings.cshl.edu/meetings/cellcy06.shtml International conference on desalination and desalination plant rehabitation. May 18-21, 2006, Sharm-El-Sheikh, Egypt. http://www.alex.edu.eg/adst/ Caribbean Academy of Sciences 15th annual meeting and conference. May 21-23, 2006, Gosier, Guadeloupe. E-mail: [email protected] First International Association of Agricultural Information Specialists (IAARD) African Chapter Conference. May 21-26, 2006, Nairobi, Kenya. http://www.asareca.org/iaald-africa/ European Cell line and Engineering. May 22-24, 2006, Renaissance, Zurich, Switzerland. E-mail:[email protected] XX International Symposium on Virus and Virus-like Diseases of Temperate Fruit Crops and XI International Symposium of Small Fruit Virus Diseases. May 22-26, 2006, Antalya, Turkey. www.fv2006.gen.tr Integrated Water Resources Management and Challenges of the Sustainable Development. May 23-25, 2006, Marrakech, Morocco. http://www.ucam.ac.ma/gire3d/anglais/index1.htm 26th Annual Conference of the International Association for Impact Assessment. May 23-26, 2006, Stavanger, Norway. http://www.iaia.org/Non_Members/Conference/IAIA06/Conf_main_ page/index.html Retroviruses. May 23-28, 2006, Cold Spring Harbor, New York, USA. http://meetings.cshl.edu/meetings/retro06.shtml 3rd EPSO Conference "Plant Dynamics: from Molecules to Ecosystems". May 28-June 1, 2006, Visegrád, Hungary. http://www.epsoweb.org/catalog/Conf2006.htm Revisiting Life Science from Half Century of Virus Research. May 30-31, 2006. Kyoto University, Japan (free). http://office.med.kyoto-u.ac.jp/siran/ JUNE Best Practices in Transfer of Science and Technology. June 1-2, 2006, Turku, Finland. http://www.astp.net/

Useful web-sites

a) An online companion to Plant Physiology, Third Edition by Lincoln Taiz and Eduardo Zeiger. Includes Essays, Topics in Plant Physiology, Study Questions and Further Readings: http://www.plantphys.net/. Also related: http://plantbiology.unibas.ch/, http://www.usu.edu/cpl/ b) A resource for information on abscisic acid, abscisic acid analogs and other related phytohormones. http://www.abscisicacid.com/. Also: http://cbr-rbc.nrc-cnrc.gc.ca/abscisicacid/ c) This site lists Plant Hormones and their characteristics and goes on to try to provide unifying 'reasons' for their effects. It is not part of current scientific thinking. http://www.pruittfamily.com/paul/plants.htm. Also related from the University of Bristol, UK: http://www.plant-hormones.info/abscisicacid.htm, d) News involving NERC, funding opportunities, details of NERC funded science and research centers. http://www.nerc.ac.uk/ e) The Photosynthesis Center at Arizona State University is a multidisciplinary group doing research in several areas of photosynthesis. Also, links to many other related sites. http://photoscience.la.asu.edu/photosyn/default.html Also related are the following sites about photosyntheis, phototropisms, photomorphogenesis: http://web.mit.edu/esgbio/www/ps/psdir.html http://members.cox.net/chlorophyll/ http://www.biologie.uni-hamburg.de/b-online/e32/32b.htm http://www.cc.jyu.fi/~aphalo/old_pages/photobio.html http://plantsinmotion.bio.indiana.edu/redirect.html f) A herbalist's site (in development) but contains useful information on a range of compounds synthesized by plants. http://www.friedli.com/herbs/phytochem/flavonoids.html g) The application of stable isotopes to forest/crop ecophysiology and palaeoeenvironmental studies. http://web.udl.es/usuaris/x3845331/invest.htm h) Plant stress. http://www.plantstress.com/ i) All about seed biology. http://www.seedbiology.de/ j) Carnivorous plants. http://www.waltraudschulze.de/carnivor/carni.html k) News and views on some of the latest developments in the broad field of biotechnology. http://www.bio.org/

First International Symposium on System Biology. June 1-2, 2006, Murcia, Spain. http://www.um.es/sysbiol2006/ X International Symposium on the Processing Tomato. June 6-8, 2006, Tunis, Tunisia. www.worldtomatocongress.com Natural Preservatives 2006. June 7-8, 2006, Amsterdam, Netherlands. www.baktoflavors.com Bangalore Bio 2006. June 7-9, 2006, Bangalore, India. http://www.bangalorebio.in/conference.htm I International Symposium on Chamomile Research, Development and Production. June 7-10, 2006, Presov, Slovak Republic. www.chamomile.szm.sk Hydrological Sciences for Managing Water Resources in the Asia. June 8-10, 2006, Guangzhou, China. Email: [email protected] International Symposium on Nanotechnology in Environmental Protection and Pollution (ISNEPP). June 18-21, 2006, Hong Kong, China, http://www.isnepp.org/ International scientific conference on desertification and drylands research. June 19-21, 2006, Tunis, Tunisia. http://www.unesco.org/mab/ecosyst/futureDrylands.shtml Training course on biotech crop commercialisation. June 19-23, 2006, Manila, Philippines. http://www.asiabiobusiness.com/ Plant Receptor Signaling. June 22-25, 2006, Ames, USA. http://www.bb.iastate.edu/%7Egfst/PSIframeset.html Therapeutic Proteins:Chemical & Enzymatic Modification. June 27, 2006, Royal Society of Chemistry (RSC), UCL, London. http://www.homepages.ucl.ac.uk/~ucbepad/protein.html JULY The 8th Peptide Forum "Innovative Methodology of Peptide Protein Synthesis and Future Perspective of Chemical Biology". July 1, 2006, Kyoto, Japan. http://www.kyoto-phu.ac.jp/coe/8peptide_forum/ IX International Conference on Grape Genetics and Breeding. July 2-6, 2006, Udine, Italy. www.grapebreeding2006.com International Symposium on Environmental Biotechnology. July 9-13, 2006, Leipzig, Germany. http://www.ufz.de/index.php?en=5570 18th World Congress of Soil Science. July 9-15, 2006, Philadelphia, USA. http://www.colostate.edu/programs/IUSS/18wcss/index.html Consultative meeting on the need for scientific equipment policies. July 12-15, 2006, Bagamoyo, Tanzania. Email [email protected] The 3rd annual Jack F. Ealy workshop on science journalism. July 12-21, 2006, California, USA. http://www.iamericas.org/spanish/events/event.html?eid=2006-5404S &isnw=1 The Fifth International Conference on Bioinformatics of Genome Regulation and Structure (BGRS'2006). July 16-22, 2006, Novosibirsk, Russia. http://www.bionet.nsc.ru/meeting/bgrs2006/ International Plant Biotechnology Symposium. July 18-21, 2006, Dar-es-Salaam, Tanzania. http://africancrops.net/biotecnet/index.htm 5th International Conference on Mycorrhiza (ICOM5). July 23-27, 2006, Granada, Spain. http://www.eez.csic.es/icom5/Index.htm ICOB-5 & ISCNP-25 (International Conference on Biodiversity and Natural Products). July 23-28, 2006, Kyoto, Japan. http://www.tennenyuuki.ne.jp/iupac/ Africa Rice Congress. July 31 ­ August 4, 2006, Dar es Salaam, Tanzania. http://www.warda.org/africa-rice-congress/rationale.html Summer course on biosafety assessment and regulation of agricultural biotechnology. July 31 ­ August 11, 2006, Ghent, Belgium. http://www.ipbo.ugent.be/ AUGUST 11th IUPAC International Congress of Pesticide Chemistry. August 8-11, 2006, Kobe, Japan. http://www.iupac2006.jtbcom.co.jp International Conference on Managing Quality in Chains. August 7-10, 2006, Bangkok, Thailand. http://www.kmutt.ac.th/mquic2006 2006 World Congress of International Association for Plant Tissue Culture And Biotechnology. August 13-17, 2006, Beijing, China. http://www.genetics.ac.cn/IAPTCB.htm XXVII International Horticultural Congress. August 13-18, 2006, Seoul (Korea). www.ihc2006.org Tropical Crop Biotechnology Conference 2006. August 16-19, 2006, Cairns, Australia. http://www.tcbc2006.com.au/

World Renewable Energy Congress IX and Exhibition. August 19-25, 2006, Florence, Italy. http://www.wrenuk.co.uk/wrecix.html International Plant Breeding Symposium. August 20-25, 2006, Mexico City, Mexico. http://www.intlplantbreeding.com/ The 16th Annual BioCity Symposium CELL STRESS. August 24-25, 2006, BioCity, Turku, Finland. http://www.biocity.turku.fi/ European Symposium on Biochemical Engineering Science. August 27-30, 2006, Salzburg, Austria. http://www.esbes2006.org/ Biolatina 2006. August 28-30, 2006, Buenos Aires, Argentina. http://www.foarbi.org.ar/ppal/ V International Symposium on Irrigation of Horticultural Crops. August 28 - September 2, 2006, Mildura, VIC, Australia. www.dpi.vic.gov.au/irrigationsymposium SEPTEMBER 52nd Brazilian Congress on Genetics. September 3-6, 2006, Foz do Iguaçu, Brazil. http://www.sbg.org.br/Divulgacao/Convite52.htm Innogen Annual Conference 2006. September 5-6, 2006, London, United Kingdom. http://www.innogen.ac.uk/Events/Annual-Conference Translational Control. September 6-10, 2006, Cold Spring Harbor, New York. http://meetings.cshl.edu/meetings/transc06.shtml BGCI's 6th International Congress on Education in Botanic Gardens. September 10-14, 2006, University of Oxford Botanic Garden, UK. http://www.bgci.org/educationcongress IWA World Water Congress and Exhibition. September 10-14, 2006, Beijing, China. http://www.iwa-beijing2006.org/show.asp XXII International EUCARPIA Symposium - Section Ornamentals: Breeding for Beauty. September 11-15, 2006, San Remo, Italy. www.istflori.it Symposium on environmental protection in the Middle East and North Africa. September 18-19, 2006, Byblos, Lebanon. http://www.sas.byblos.lau.edu.lb/Events/Handzettel-04-November-20 05.pdf Global conference on renewable energy approaches for desert regions. September 18-22, 2006, Amman, Jordan. http://www.ju.edu.jo/confernces/gcreader/index.htm 4th Recombinant Protein Production Meeting. September 21-23, 2006, Barcelona, Spain. http://www.rpp2006.com/ ComBio2006. September 24-28, 2006, Brisbane, Australia. http://www.asbmb.org.au/combio2006/index.html European Biomarkers Summit. September 26-27, 2006, Prague, Czech Republic. http://www.selectbiosciences.com/conferences/biomarkers2006/ RNAi Europe 2006. September 28-29, 2006, Prague, Czech Republic. http://www.selectbiosciences.com/conferences/rnaieurope2006/ OCTOBER I International Symposium Contribution of African Botanica to Humanity. October 3-7, 2006, N'Zérékoré, Guinea. www.botaniqueafricaine.com World Congress on Emulsions. October 3-7, 2006, Lyon, France. www.cme-emulsion.com Plant GEMs 5. October 11-14, 2006, Venice, Italy. www.plant-gems.org I International Symposium on Pomegranate and Minor Mediterranean Fruits. October 16-17, 2006, Adana, Turkey. www.cu.edu.tr/fakulteler/zf/bkb/ispm/ Advances in Nano-biotechnology. October 19-20, 2006, Innsbruck, Austria. http://www.innano.org/ II International Symposium on Saffron Biology and Technology ISSBT. October 28-30, 2006, Mashhad (Iran). saffron-ir.um.ac.ir Models for Plant Growth, Environmental Control & Farm Management in Protected Cultivation - HortiModel2006. October 29 - November 2, 2006, Wageningen, Netherlands. www.hortimodel2006.nl NOVEMBER 2nd International Symposium on Biomolecules and Related Compounds. November 10-12, 2006, Kyoto, Japan. http://www.kyoto-phu.ac.jp/2nd_isb/

The 19th Naito Conference. Molecular Basis for Maintenance and Differentiation of Stem Cells [II]. November 14-17, 2006, Tokyo, Japan. [email protected] Workshop on Tropical and Subtropical Fruits. November 20-23, 2006, Chiang Mai, Thailand. [email protected] DECEMBER First international meeting on cassava plant breeding and biotechnology. December 1-5, 2006, Brasilia, Brazil, http://www.geneconserve.pro.br/meeting/ IV International ISHS Symposium and VIII National Symposium on Seed, Transplant and Stand Establishment of Horticultural Crops. December 3-6, 2006, San Antonio, TX, USA. sest2006symposium.tamu.edu Society-in-Science - African Forum. December 3-6, 2006, Port Elizabeth, South Africa. http://www.fest.org.za/ascc/

How to reference an article or section from Global Plant Letters?

You may be interested in referencing an article, comment or section from Global Plant Letters. Two examples are listed below which serve as reference models: Deng S, Lu Y (2006) The Mesozoic dicksoniaceous ferns: characteristics, distribution, origin and evolutionary trend. Global Plant Letters 1(1), 9-29 Teixeira da Silva JA (2006) Flower fragrance and scent. Global Plant Letters 1(1), 38-39

Call for submissions and assistance.

ISFOP members and non-members alike are called upon to make a contribution to future Issues of Global Plant Letters. Contributions may be in the form of original research articles, reviews, comments, topical issues or other important information that pertains directly to ornamentals or floricultural crops. Should you have important results or information pertaining to other plant species or organisms but that would show potential for ornamental scientists, e.g. novel techniques, then these would also be suitable for Global Plant Letters. In addition, members who wish to assist in the compilation of "Scientific Summary" are warmly invited to contact the Editor-in-Chief for details. All submissions, comments and recommendations should be addressed to the Editor-in-Chief, Global Plant Letters, Dr. Jaime A. Teixeira da Silva, should contain a cover letter, and should be submitted via e-mail to [email protected] We look forward to your active participation.

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