Studies in floral biology are largely concerned with how flowers function to promote pollination and mating. The role of pollination in governing mating patterns in plant populations inextricably links the evolution of pollination and mating systems. Despite the close functional link between pollination and mating, research conducted for most of this century on these two fundamental aspects of plant reproduction has taken quite separate courses. This has resulted in suprisingly little cross-fertilization between the fields of pollination biology on the one hand and plant mating-system studies on the other. The separation of the two areas has largely resulted from the different backgrounds and approaches adopted by workers in these fields. Most pollination studies have been ecological in nature with a strong emphasis on field research and until recently few workers considered how the mechanics of pollen dispersal might influence mating patterns and individual plant fitness. In contrast, work on plant mating patterns has often been conducted in an ecological vacuum largely devoid of information on the environmental and demographic context in which mating occurs. Mating-system research has been dominated by population genetic and theoretical perspectives with surprisingly little consideration given to the proximate ecological factors responsible for causing a particular pattern of mating to occur.

The Conference on Tropical Rainforest Research: Current Issues was organised by the University of Brunei Darussalam and The Royal Geographical Society, London, and held in Bandar Seri Begawan, Brunei Darussalam, over 8 days in April 1993. Over 160 participants from 22 countries attended the Conference, which was opened on the 9th April by the Brunei Darussalam Minister for Home Affairs, Yang Berhormat Pehin Orang Kaya Laila Setia Bakti Diraja Dato Laila Utama Haji Awang Isa bin Datu Perdana Menteri Dato Laila Utama Haji Awang Ibrahim. The conference was initially intended to provide a forum to present the results of the expedition into the lowland mixed dipterocarp forest of the Temburong District of Brunei Darussalam, which had been jointly organised by the University of Brunei Darussalam and The Royal Geographical Society, London. The 15-month expedition, lasting from January 1991 to March 1992, was based at the then newly-completed Kuala Belalong Field Studies Centre, a research and education facility set up by the University with funds provided by the Brunei Government and Brunei-Shell Petroleum Sdn Bhd. The expedition, with over 70 scientists taking part, received financial support from a wide range of sponsors and Corporate Patrons, including Royal Brunei Airlines, the Baring Foundation, Daiwa-Dicam, Greencard Trust, the Hongkong Bank, Morgan Grenfell and Nomura-Nimco. The conference itself was supported by donations from Brunei-Shell Sdn Bhd, Royal Brunei Airlines and Standard Chartered Bank.

The West African Sahel is the transition zone between the Saharadesert in the north of Africa and the more humid Sudanian zones in the south. Although diverse in many ways, the Sahelian countries have the common problem of a fragile agricultural sector. This predicament is mainly caused by low inherent soil fertility, limited and unpredictable rainfall, frequent droughts, and wind erosion that accelerates soil degradation and desertification, compounded by To assure food production in the future, means rapidly growing populations. of declining soil fertility and increasing must be found to offset the trends soil degradation through wind erosion. This is a challenge for agricultural research. Since 1985, the Special Research Program 308 'Adapted Farming in West Africa' at the UniversityofHohenheimin collaboration with the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in Niger, has pursued the developmentof agricultural innovations for smallholder farmers in one of the most ecologically fragile regions of the world. The prevention of soil degradation, the restoration and maintenance of soil fertility, and the increase of land and labor productivity are key objectives of this multidisci plinary research program. From the beginning, a major focus of research has been wind erosion.

Nearly twenty years have passed since the publishing of a broadly-based texthook on hiolog ical control (Huffaker and Messinger 1976). In the interim, other works on biological control have been either briefer treatments (DeBach and Rosen 1991), or collections of essays on selected topics (Waage and Greathead 1986; Mackauer and Ehler 1990). Our text has been written to fill what we believe is a need for a well-integrated, broadly-based text of appropriate length and degree of technical detail for teaching a one semester upper level course in hiological control. We have attempted to focus on principles and concepts, rather than on biological control of particular taxa or hiological control by particular kinds of natural enemies. Therefore, for example, the reader will find the material on biological control of weeds integrated with biological control of insects and mites into chapters on principles, techniques, and applications rather than presented separately. Only biological control of plant pathogens is addressed independently, an appraoch made necessary by the many special features and concepts in plant pathogen biological control."

The last decade has seen tremendous progress in our knowledge of the pollen development and gene expression on one hand and the characterization of pollen specific proteins on the other. In compiling the chapters for this volume, we have pragmatically categorized these basic developments in pollen molecular biology and biotechnology into two sections based on their applications in agricul ture and implications in medicine. Pollen developmental biology and gene expression: applications in agricul ture. Pollen development is an extremely complex process encompassing a series of biochemical, physiological and genetic events. At the basic level, sporophyt ically expressed genes may expound our knowledge of unique processes of cellular differentiation which ultimately give rise to a full-fledged organism. At the applied level, the studies on the pollen and male sporophyte-specific gene expression, and of promoters and transcription factors of relevant genes have the potential to manipulate the fertility in certain cash crops leading to agricultural biotechnology."

Plants are composed of 17 essential and at least 5 beneficial elements, and these must be taken up as metal or nutrient ions to allow for growth and cell division. Much effort has been devoted to studying the physiology and biochemistry of metals and nutrients in plants. The aspect of cell biology, however, is an emerging new field and much needs to be learned about sensing, long-distance communication within plants, and cellular signal transduction chains in response to environmental stress. Cellular malfunction and consequently disease result when any of the key steps in metal and nutrient homeostasis are disrupted. Working together, leading experts in their respective fields provide a new concept that reaches beyond plant nutrition and plasmalemma transport into cellular physiology. Each chapter contains basic information on uptake, physiological function, deficiency and toxicity syndromes, long-distance and intracellular transport. The discussion is devoted to metals and nutrients where recent progress has been made and highlights the aspects of homeostasis and sensing, signaling and regulation, drawing parallels to other organisms including humans. Finally, the book identifies gaps in our current knowledge and lays out future research directions.

Currently one of the hottest topics in biochemistry, the concept of molecular chaperones has challenged the paradigm of protein self-assembly. Key figures in many disciplines review all aspects of molecular chaperones in this volume, which arises from a Royal Society discussion meeting. Overview chapters discuss the significance of chaperones in biochemistry, molecular genetics and cell biology. Each chapter is well referenced providing access to the literature.

Achievements today in plant biotechnology have already surpassed all previous expectations. Plant biotechnology, integrated with classical breeding, is now on the verge of creating the evergreen revolution' to solve the world's envisaged tripled demand for food, agricultural commodities and natural products. New biotechnologies are being continuously adapted to agricultural practices, opening new vistas for plant utilization. Plant biotechnology is changing the plant scene in three major areas: (1) growth and development control (vegetative, generative and propagation), (2) protecting plants against the ever-increasing threats of abiotic and biotic stress, (3) expanding the horizons by producing specialty foods, biochemicals and pharmaceuticals. The potential for improving plant and animal productivity and their proper use in agriculture relies largely on newly-developed DNA biotechnology and molecular markers. These techniques enable the selection of successful genotypes, better isolation and cloning of favorable traits, and the creating of transgenic organisms of importance to agriculture. These areas were extensively discussed at the 9th international congress of the International Association of Plant Tissue Culture and Biotechnology, Plant Biotechnology and In Vitro Biology in the 21st Century', which was held in Jerusalem in June 1998. The present book of proceedings contains the variety of scientific achievements and techniques that were presented: Basic and Applied Aspects of Growth, Development and Differentiation; Genetic Manipulations: Transformation and Gene Expression, Hybridization, Haploidization and Mutagenesis; Genetic Stability and Instability, Selection and Variability; Regulation of Primary and Secondary Metabolism; Model Systems: Cell Cycle, Transport and Signal Transduction; Biotechnology for Plant Protection: Abiotic and Biotic Stress; Biotechnology for Crop Improvement: Yield, Quality and Production of Valuable Substances; Novel Micropropagation Methods; New Markets and Commercial Applications; Intellectual Property Rights.

Significant developments in recent years have led to a deeper understanding of the role and function of carotenoids in photosynthesis. For the first time the biological, biochemical, and chemical aspects of the role of these pigments in photosynthesis are brought together in one comprehensive reference volume. Chapters focus on the photochemistry of carotenoids in light harvesting and photoprotection, the nature and distribution of carotenoids in photosynthetic organisms, their biosynthesis, the herbicidal inhibition of carotenogenesis and the xanthophyll cycle'. Throughout details are given of the various methodologies used. A detailed appendix provides physical data for the major compounds. Carotenoids in Photosynthesis is an invaluable reference source for all plant scientists.

Preface; A. Altman, Y. Waisel. Diversity of Roots: The Place of Roots in Plant Development and the Diversity of Root Types; P.W. Barlow, B. Palma. Induction of Roots and Their Development: Indissociable Chief Actors in the Inductive Phase of Adventitious Rooting; T. Gaspar et al. Hormonal Control of Root Induction and Development: Increased Induction of Adventitious Rooting via Slow Release Auxins and Elicitors; van der Krieken et al. Molecular Biology of Root Development: Auxin Induced Gene Expression During Rooting of Loblolly Pine Stem Cuttings; B. Goldfarb et al. Ecological Aspects of Root Development: Shootborne Roots: An Adaptive Organ in Sand Dunes; A. Danin. Applied Aspects of Root Development: Relations between Early Root Growth and Flower Yield of Clonal Rose Rootstocks; D.P. de Vries, L.A.M. Dubois. Root Products: Insane Roots and Twisted Carrots: Physiology and Biochemistry of Root Specific Metabolites; H.E. Flores. Models and Methods for Root Study: Morphological Structured Model for Hairy Root Culture; I. Berzin et al. Concluding Remarks: A 1996 Overview of the Research Interests from the Jerusalem Symposium T. Gaspar. 71 additional articles. Index.

Many organisms have evolved the ability to enter into and revive from a dormant state. They can survive for long periods in this state (often even months to years), yet can become responsive again within minutes or hours. This is often, but not necessarily, associated with desiccation. Preserving one's body and reviving it in future generations is a dream of mankind. To date, however, we have failed to learn how cells, tissues or entire organisms can be made dormant or be effectively revived at ambient temperatures. In this book studies on organisms, ranging from aquatic cyanobacteria that produce akinetes to hibernating mammals, are presented, and reveal common but also divergent physiological and molecular pathways for surviving in a dormant form or for tolerating harsh environments. Attempting to learn the functions associated with dormancy and how they are regulated is one of the great future challenges. Its relevance to the preservation of cells and tissues is one of the key concerns of this book.

Ascorbate acid (AsA) is an important antioxidant in plants, playing important roles in various physiological processes. Humans have lost the ability to synthesize AsA because of the lack of L-gulono-1,4-lactone oxidoreductase, and thus have to absorb ascorbate from diet including fresh fruits and vegetables, as they are the major sources of ascorbate. Several pathways for AsA biosynthesis and metabolism have been identified in plants since 1998. More attention has been paid to improving ascorbate content in plants especially in fruits and vegetables. Significant progresses have been made on key enzymes and genes involved in the AsA biosynthesis and metabolism. Recently, more interests have arised in the regulation of AsA biosynthesis, as it is constantly regulated by the plant development and the environmental factors, e.g. light. Ascorbic acid is also frequently reported to affect plant growth and development e.g. flowering time and fruit ripening. The scope of the book is to cover the biological role, biosynthesis and metabolism, regulation, and metabolic modification of ascorbate in plants.

Note Not long after publication of Orchid Biology, Reviews and Perspectives (OB) volume VII, my co-editor, Dr. Alec M. Pridgeon informed me that the pressure of other duties, especially the editing of Genera Orchidacearum (GO) will make it impossible for him to continue as co-editor and eventually editor ofthe series. Alec is an excellent orchid scientist and editor. I was sorry to that he had to leave OB, but glad that GO will be in his able hands. The first volume of GO attests to his considerable abilities and I wish him much success in the future. Editors of orchid publications are not the most common of species (to use a botanical analogy) and finding a replacement for Alec was not easy. However I was fortunate that Dr. Tiiu Kull agreed to become my co-editor and eventually take over the series. As is obvious from the Contributors section Dr. Kull has extensive experience as both writer and editor. My interactions with her while editing this volume have convinced me she is an excellent choice. Scientifically she brings to OB an appreciation and understanding of northern terrestrial orchids, a group, which has not received as much attention as it deserves. Another addition to OB is Dr. Tim Wing Yam who agreed to become an associate editor. Tim, who holds a position at the Singapore Botanic Gardens, will provide expertise on seed germination, hybridization, tissue culture, species and conservation.

With one volume each year, this series keeps scientists and advanced students informed of the latest developments and results in all areas of the plant sciences. The present volume includes reviews on genetics, cell biology, physiology, comparative morphology, systematics, ecology, and vegetation science.

Nematode interactions are important biological phenomena and of great significance in agriculture. It is a fascinating subject which is multidisciplinary by nature, and concerns any scientist involved with plant health. There have been marked advances in our knowledge of various aspects of the subject in the last two decades. This study area has been the subject of several reviews, but there was no exclusive text on the subject. This has stressed the need to document the information, developing a unifying theme which treated nematode interactions in a holistic manner. This book is about the inter action of plant-parasitic nematodes with other plant pathogens or root symbionts, the nature of their associations, their impact on the host and con sequential interactive effects on the involved organisms. Since nematodes are at the centre of the theme, the responsibility of understanding of other plant pathogens dealt with in this book is largely delegated to the reader. I have limited the book content to interactions with biotic pathogens and root symbionts only, for various reasons. The book embodies 16 chapters, and attempts to present balanced infor mation on various aspects of nematode interactions with other plant pathogens and root symbionts. Some chapters describe general aspects of the subject. Interactions of nematodes with specific groups of organisms are addressed in the remaining chapters."

Sixty years ago at the Waite Agricultural Research Institute, G. Samuel, a plant pathologist, and C. S. Piper, a chemist, published their conclusion that the cause of roadside take-all, a disease of oats, was manganese deficiency. This report, together with the concurrent and independent studies of W. M. Carne in Western Australia were the first records of manganese deficiency in Australia and came only six years after McHargue's paper which is generally accepted as the final proof of the essentiality of this element. There must have been a few doubts for some people at the time, however, as the CAB publication, 'The Minor Elements of the Soil' (1940) expressed the view that further evidence to this effect was provided by Samuel and Piper. Their historic contributions are recognised by the International Symposium on Manganese in Soils and Plants as it meets on the site of their early labours to celebrate the 60th anniversary. This year Australians also acknowledge 200 years of European settlement in this country and so the Symposium is both a Bicentennial and a diamond jubilee event which recognises the impact of trace elements on agricultural development in Australia. In a broader sense, a symposium such as this celebrates, as it reviews, the efforts of all who over the ages have contributed to our knowledge of manganese in soils and plants.

The activation of carbon dioxide by transition metal complexes has been extensively studied. both experimentally and theoretically. 1 Central reactions in this chemistry are the insertion of C02 into M-X bonds. where X = H. C. 0. and N. (eq. 1-4). We are presently investigating the mechanistic aspects of these reaction processes and will herein deSCribe our current level of understanding. Comparisons of the pathway of the carbon-carbon bond fonning process in transition metal chemistry with the well known analogous chemistry involving organolithium reagents will be presented. Furthermore. the role of these reaction types in both homogeneous and heterogenous catalytic processes leading to useful chemicals will be elaborated. _OM> (1) lMt-H + ~ lMlopi _OM> (2) [Mt-R + C0. 2 [M]0. 2CR _OM> (3) [Mt-OR+ ~ [M]0. 2COR _OM> (4) [Mt-NR2 + C0. 2 [M]~CNR2 Insertion of C02 into the Metal-Hydride Bond. The reaction of anionic group 6 (Cr. Mo. W) transition metal hydrides with carbon dioxide to afford metalloformates occurs readlly at ambient temperature and 2 reduced pressures of carbon dioxide. This insertion process is referred to the normal pathway (Scheme 1). There are no documented cases of C02 insertion into the metal hydride bond to provide the alternative. metallocarboxylic acid. isomer (referred in Scheme 1 as abnormal). 3 Recent theoretical studies ascribe this preference to an unfavorable electrostatic interaction and poorer orbital overlap in the latter pro 4 cess. Nevertheless.

The study of plant development in recent years has often been concerned with the effects of the environment and the possible involvement of growth substances. The prevalent belief that plant growth substances are crucial to plant development has tended to obscure rather than to clarify the underlying cellular mechanisms of development. The aim in this book is to try to focus on what is currently known, and what needs to be known, in order to explain plant development in terms that allow further experimentation at the cellular and molecular levels. We need to know where and at what level in the cell or organ the critical processes controlling development occur. Then, we will be better able to under stand how development is controlled by the genes, whether directly by the continual production of new gene transcripts or more indirectly by the genes merely defining self-regulating systems that then function autonomously. This book is not a survey of the whole of plant development but is meant to concentrate on the possible component cellular and molecular processes involved. Consequently, a basic knowledge of plant structure is assumed. The facts of plant morphogenesis can be obtained from the books listed in the General Reading section at the end of Chapter 1. Although references are not cited specifically in the text, the key references for each section are denoted by superscript numbers and listed in the Notes section at the end of each chapter."

The Second International Oat Conference. of which these are the proceedings.was heldat Aberystwyth. 15-18 July.1985. In thebusiness meeting heldatthecloseof theFirstInternational Oat Workshop that was held at PennsylvaniaStateUniversity in 1982. an Internat i ona1 Organsi i ng Committee under the chairmanship of Or KJ Frey was electedto organisethe next conference.and Aberystwyth was proposed and agreed as the venue. The final date of the Second Conferenceand the out 1i ne of the programme. inc1udi ng selection of the rnain speakers. was agreed by the Internat i ona1 Committee but 1oca1 arrangements and finalisation of the programme were delegatedto a local sub-committee centredat the Welsh Plant Breeding Station. We wish to record our appreciationof the work done bythis localcommittee in assuming various organisational responsibilities. From the outsettherewas a firm committmentto makethe Conferenceas international as possible and every effortwas made both to provide a programme thatwouldattract participants from allpartsof the worldand to keep costs to a minimum so as to increasethe chances of potential delegatesbeing ableto attend. Alistof participantsis includedbut it is worthyof notethattwenty-three countr ies were represented. The Conferencewas organisedintoseven half-daysessions. Six of these covered differenttopics relevantto the improvement of oats and the seventhwas a visit to the Welsh PlantBreedingStationwhere laboratory and fieldwork ontheoatcrop was demonstrated.

In 1971, the late Dr. J. Kolek of the Institute of Botany, Bratislava, organized the first International Symposium devoted exclusively to plant roots. At that time, perhaps only a few of the participants, gathered together in Tatranska Lomnica, sensed that a new era of root meetings was beginning. Nevertheless, it is now clear that Dr. Kolek's action, undertaken with his characteristic enormous enthusiasm, was rather pioneering, for it started a series a similar meetings. Moreover, what was rather exceptional at the time was the fact that the meeting was devoted to the functioning of just a single organ, the root. One possible reason for the unexpected success of the original, perhaps naive, idea of a Root Symposium might lie with the fact that plant roots have always been extremely popular as experimental material for cytologists, biochemists and physiologists whishing to probe processes as diverse as cell division and solute transport. Of course, the connection of roots with the rest of the plant is not forgotten either. This wide variety of disciplines is now coupled with the development of increasingly sophisticated experimental techniques to study some of these old problems. These factors undoubtedly contribute to the necessity of continuing the tradition of the root symposia. The common theme of root function gives, in addition, a certain unity to all these diverse activities.

Cyanobacterial symbioses are no longer regarded as mere oddities but as important components of the biosphere, occurring both in terrestrial and aquatic habitats worldwide. It is becoming apparent that they can enter into symbiosis with a wider variety of organisms than hitherto known, and there are many more still to be discovered, particularly in marine environments. The chapters cover cyanobacterial symbioses with plants (algae, bryophytes, Azolla, cycads, Gunnera), cyanobacterial symbioses in marine environments, lichens, Nostoc-Geosiphon (a fungus closely related to arbuscular mycorrhiza fungi) symbiosis, and artificial associations of cyanobacteria with economically important plants. In addition, cyanobiont diversity, sensing-signalling, and evolutionary aspects of the symbiosis are dealt with. Renowned experts actively involved in research on cyanobacterial symbioses deal with ecological, physiological, biochemical, molecular, and applied aspects of all known cyanobacterial symbioses.
This volume on cyanobacteria in symbiosis complements the two earlier volumes on cyanobacteria published by Kluwer (Molecular Biology of Cyanobacteria, edited by D.A. Bryant and Ecology of Cyanobacteria, edited by B.A. Whitton and M. Potts). Together, the three volumes provide the most comprehensive treatment of cyanobacterial literature as a whole. The book will serve as a valuable reference work and text for teaching and research in the field of plant-microbe interactions and nitrogen fixation.

These proceedings of a workshop of the International Association for Phytoplankton Taxonomy and Ecology are directed specifically at the relationship between phytoplankton ecology and the trophic status of water bodies. Contributions address the fact that distinctive assemblages of phytoplankton species are closely associated with particular categories of water bodies. Particular attention is paid to how communities are assembled and to the ways in which environmental constraints filter the successful species. Overview articles are included. The book will be a valuable source of information to limnologists, algologists, and the technical staff of all water suppliers.

Historically, scientists and laymen have regarded salinity as a hazar dous, detrimental phenomenon. This negative view was a principal reason for the lack of agricultural development of most arid and semi arid zones of the world where the major sources of water for biological production are saline. The late Hugo Boyko was probably the first scientist in recent times to challenge this commonly held, pessimistic view of salinity. His research in Israel indicated that many plants can be irrigated with saline water, even at seawater strength, if they are in sandy soil - a technique that could open much barren land to agriculture. This new, even radical, approach to salinity was clearly enunciated in the book he edited and most appropriately entitled 'Salinity and Aridity: New Approaches to Old Problems' (1966). A decade later, three members of the United States National Science Foundation (NSF), Lewis Mayfield, James Aller and Oskar Zaborsky, formulated the 'Biosaline Concept'; namely, that poor soils, high solar insolation and saline water, which prevail in arid lands, should be viewed as useful resources rather than as disadvantages, and that these resources can be used for non-traditional production of food, fuels and chemicals. The First International Workshop on Biosaline Research was con vened at Kiawah Island, South Carolina, in 1977 by A. San Pietro.

This book provides a comprehensive and interactive view of recent advances in the cytology, anatomy, and physiology of roots as presented at the 5th International Symposium on Structure and Function of Roots, held on 31 August-4 September, 1998, in Stara Lesna, Slovakia. This edition differs from previous ones by including some aspects of functional genetics and plant morphogenesis. The book is intended to serve both students and researchers as a valuable source of updated information, ideas, and concepts dealing with the most fundamental questions of development and function of plant roots.

A growing interest has been shown recently in the dymanics of nitrogen in agricultural and natural ecosystems. This has been caused by increasing demands for food and fibre by a rapidly expanding world population, and by a growing concern that increased land clearing, cultivation and use of both fertilizer and biologically fixed nitrogen can have detrimental effects on the environment. These include effects on water quality, eutrophication of surface waters and changes in atmospheric composition all caused by increased cycling of nitrogenous compounds. The input and availability of nitrogen frequently affects the productivity of farming systems more than any other single management factor, but often the nitrogen is used inefficiently. Much of the fertilizer nitrogen applied to the soil is not utilised by the crop: it is lost either in solution form, by leaching of nitrate, or in gaseous forms as ammonia, nitrous oxide, nitric oxide or dinitrogen. The leached nitrate can contaminate rivers and ground waters, while the emitted ammonia can contaminate surface waters or combine with atmospheric sulfur dioxide to form aerosols which affect visibility, health and climate. There is also concern that increased evolution of nitrous oxide will deplete the protective ozone layer of the stratosphere. The possibility of a link between the intensity of agricultural use of nitrogen, nitrous oxide emissions and amounts of stratospheric ozone has focussed attention on these interactions.