Written by the leading experts in the field, this book examines the evolutionary advantages of gender dimorphism - the occurence of two sexual forms - and sexual dimorphism - dimorphism in secondary sex characters - in flowering plants. Gender dimorphism is found in approximately 10% of flowering plant species and has been an active topic of research. By contrast, sexual dimorphism in plants is much less widely appreciated. The book consists of three sections: The first introduces readers to the tremendous variety of breeding systems and their evolution in plants and sets the stage for a consideration of the evolution of dimorphism in reproductive and non-reproductive characters. The second section deals with the evolution of secondary sexual characters, including the theory related to the evolution of sexual dimorphism and its empirical patterns. The last section deals with the genetics of gender expression and of secondary sexual characters.

This book serves as the first comprehensive compilation describing the breeding strategies and genetics and genomics of the coconut palm. It describes gene evolution of economically important traits such as oil biosynthesis, aroma and fragrance, disease-resistant genes and small RNAs-mediated gene regulation of coconut. Application of "omics" approaches in palms and the prospects of genome editing technologies in coconut are also discussed. The author list includes pioneers and experts in the field of coconut genomics. The book appeals to postgraduate students, researchers and industry players in the field of plantation crops in general and coconut in particular.

The book contains the proceedings of the Fifth International Wheat Conference at which leading international scientists reviewed current research issues and developments in wheat improvement. The debated topics cover breeding and genetics, genetic resources and importance of free germplasm exchange, breeding for biotic and abiotic stresses, physiology, agronomy and mineral nutrition, grain quality and biotechnology. A significant number of presentations were made by participants from the former USSR and Eastern and Central Europe, making this book also a prime reference for current wheat research and production status in these countries. This book provides an opportunity for wheat scientists interested in global wheat improvement issues to obtain an insight into the research that is currently being conducted worldwide and the prospects of further improvement to meet the increasing demands for this food commodity.

The beginnings of human civili zation can be traced back to the time , ne- ly 12 ,000 years ago , when th e early humans gradually ch anged from a life of hunting and gathering food , to producing food. This beginning of pri- tive agriculture ensured a dependable supply of food , and fostered the living together of people in groups and the development of s o c i e ty. During th is time, plant s e e ds were recognized a s a valuable s o ur c e of food and nutrition , and began to be used for growing plants for food. Ever s i n c e , plant seeds have played an important role in the development of the human civilization . Even today, s e e ds of a few crop s p e c i e s , s uc h as the cereals and legume s, are the primary s o u r c e of most human food , and the predominant commodity in international agriculture. Owing to their great importance as food for human s and in international trade , seeds have been a favorite object of s t u d y by developmental biologists and physiologi sts , nutritionist s and chem i sts . A wealth of useful information i s available on th e biology of seed s .

These Proceedings evolved from the OECD Co-operative Research Programme workshop on "Potential ecological impact of transgenic plants expressing viral sequencies," held at the Agricultural Biotechnology Center in Godollo, Hungary on 24-26 April 1997. The OECD Co-operative Research Programme At the Directorate for Agrieulture of the Organisation for Economie Co-operation and Development (OECD) a co-operative research programme for "Biological Resource Management" has existed since 1990. It foeuses on work in four specific topie areas, one of whieh is "Ecology and utilisation of new organisms" (Theme 3). The activities promoted by this programme are post-doctoral fellowships (announced annually), and the organisation of expert workshops (1-2 workshops per Theme per year). The 26 OECD member countries participating in this programme are: Australia, Austria, Belgium, Canada, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Ireland, ltaly, Korea, Japan, the NetherIands, New Zealand, Norway, Poland, Portugal, Spain, Sweden, SwitzerIand, Turkey, the UK, and the USA."

Micropropagation of plants is a multi billion dollar industry being practiced in hundreds of sm all and large nurseries and commerciallabo- ratories throughout the world. At present, it is the only component of plant biotechnology which has been commercially exploited on such a large scale, especially for the production of ornamentals. Now micropropagation of trees and medicinal plants has also assumed great importance. With recent progress made in the propagation of fruit and forest trees, and the immediate need for afforestation and planting of orchards, propagules and plantlets are required quickly and in large numbers. Taking these points into consideration High-Tech and Micropropagation I, II, III, and IV were published in 1991 and 1992. The present two volumes, High-Tech and Micropropagation V and VI, comprise 51 chapters contributed by international experts from 24 countries. High-Tech and Micropropagation V comprises 24 chapters arranged into the following three seetions: 1. Vegetables and fruits (garlic, Amaranthus, Brassica oleracea, pep- per, watermelon, cassava, banana, Myrtus communis, passionfruit, Polymnia sonchifolia, pepino, and spinaeh) H. Grasses (bamboos, Caustis dioica, Dendrocalamus, Miscanthus x giganteus, sugarcane) In. Trees (Aegle marmelos, Eucalyptus, Fraxinus excelsior, luglans cinerea, Pinus virginiana, Prosopis, and Vlmus species) High-Tech and Micropropagation VI comprises 27 chapters arranged in two sections: 1. Ornamental and aromatic plants (Amaryllis, Anthurium, Blandfordia, bromeliads, Campanula, Coleus, Ctenanthe, Cyclamen, Daphne, Dracaena, Gerbera, Helianthemum, Hippeastrum, Leucojum, Mammillaria, Maranta, Mediocactus, Mussaenda, Narcissus, Otacanthus, ponytail palm, Prunus tenella, Spiranthes, and Zinnia) II.

Micropropagation of plants is a multibillion dollar industry being prac- ticed in hundreds of small and large nurseries and commercial labora- tories throughout the world. At present, it is the only component of plant biotechnology which has been commercially exploited on such a large scale, especially for the production of ornamentals. Now micro- propagation of trees and medicinal plants has also assumed great im- portance. With recent progress made in the propagation of fruit and forest trees, and the immediate need for afforestation and planting of orchards, propagules and plantlets are required quickly and in large numbers. Taking these points into consideration High-Tech and Micro- propagation I, If, If I, and IV were published in 1991 and 1992. The present two volumes, High-Tech and Micropropagation V and VI, com- prise 51 chapters contributed by international experts from 24 countries. High-Tech and M icropropagation V comprises 24 chapters arranged into the following three sections: I. Vegetables and fruits (garlic, Amaranthus, Brassica oleracea, pepper watermelon, cassava, banana, Myrtus communis, passionfruit, Poly- mnia sonchifolia, pepino, and spinach) II. Grasses (bamboos, Caustis dioica, Dendrocalamus, Miscanthus x giganteus, sugarcane) III. Trees (Aegle marmelos, Eucalyptus, Fraxinus excelsior, Juglans cinerea, Pinus virginiana, Prosopis, and Ulmus species) High-Tech and Micropropagation VI comprises 27 chapters arranged in two sections: I.

The International Centre for Advanced Mediterranean Agronomic Studies (CIHEAM), established in 1962, is an intergovernmental organization of four teen countries: Albania, Algeria, Egypt, France, Greece, Italy, Lebanon, Malta, Morocco, Portugal, Spain, Tunisia, Turkey and Yugoslavia. Four institutes (Bari, Italy; Chania, Greece; Montpellier, France and Zaragoza, Spain) provide post-graduate education at the Master of Science level. CIHEAM promotes research networks on Mediterranean agricultural priorities, supports the organization of specialized education in member countries, holds seminars and workshops bringing together technologists and scientists involved in Mediterranean agriculture and regularly produces diverse publications including the series 'Options Mediterraneennes'. Through these activities, CIHEAM promotes North/South dialogue and international co-operation for agricultural development in the Mediterranean region. Plant breeding is, since 1982, one of the fields in which CIHEAM is con ducting a programme of training and promotion of research, through its Mediterranean Agronomic Institute of Zaragoza. The programme includes a one-year advanced specialization course, a series of two-week courses for professionals, and support for collaborative research activities in Mediterranean-relevant species. Many of these activities are organized in col laboration with national and international institutions. The publication in 1993 of Plant Breeding. Principles and Prospects, which ini tiated the Chapman & Hall's Plant Breeding Series, has become an important feature of CIHEAM's plant breeding programme. We are now pleased to add a further volume to that series: the present book, Statistical Methods for Plant Variety Evaluation."

Red clover (Trifolium pratenseL. ) is an important forage of most ofthe tem- perate regions of the world, and atone time was the most importantlegume for hay in the United States. Oddly enough,red clover has never been the subject ofa monograph, although its culture has been discussed in many monograph chapters in the United States and Europe, perhaps beginning with those of Westgate and Hillman ina USDAFarmers Bulletin in 1911and early Swedish publications. The monograph "CloverScience and Technology" published in 1985 provides coverage of red clover along with other Trifolium species. It was theobjective of thepresentmonograph, "Red Clover Science" toexamine the literature published on red clover primarily after 1984. Perhaps the tim- ing of this publication is appropriate with the present interest in sustainable agriculture ofwhich red clover was so prominent in the past. Red clover and other forage legumes are valuable for reducing our reliance on fossil fuels, and for reducing pollution of our soil, water, and atmosphere primarily from use of chemical nitrogen and other fertilizers. In each chapter, an attempt was made to summarize the earlierinformation and to integrate the recent findings into this background. References earlier than 1984 are included only when necessary for historical purposes. No attempt was made to review the many aspects of clover culture that has been described thoroughly in earlier pub- lications. The literature covered is necessarily worldwide becauseofpresent greater emphasis in northern Eurasia than in United States.

In a new series in plant conservation sponsored by the World Wide Fund for Nature (WWF), this book is a practical guide to a subject of increasing concern to the conservation biologist. As with each of the books in the series, this book aims to give an authoritative guide to the subject in a clear, jargon-free style. It should therefore not only be of interest to the academic biologist interested in the phenomenon of invasion, but also to government and non-governmental personnel involved in the decision-making process needed as a result of the problems encountered with invasive species. Case-studies highlight specific problems from a wide range of countries, including North America, South and Central America, Africa, Australasia, South and South East Asia, Europe, the Pacific and Atlantic Islands and Indonesia. The book contains an appendix with a list of invasive species and their countries of origin. A bibliography contains reference to all cited articles and books. This book should be of interest to conservation biologists, economic botanists, ethnobotanists, plant ecologists, agriculturalists, those interested in development problems, geographers, environmental scientists, ecotourists and "green" lay people.

Since the beginning of agricultural production, there has been a continuous effort to grow more and better quality food to feed ever increasing popula tions. Both improved cultural practices and improved crop plants have al lowed us to divert more human resources to non-agricultural activities while still increasing agricultural production. Malthusian population predictions continue to alarm agricultural researchers, especially plant breeders, to seek new technologies that will continue to allow us to produce more and better food by fewer people on less land. Both improvement of existing cultivars and development of new high-yielding cultivars are common goals for breeders of all crops. In vitro haploid production is among the new technologies that show great promise toward the goal of increasing crop yields by making similar germplasm available for many crops that was used to implement one of the greatest plant breeding success stories of this century, i. e., the development of hybrid maize by crosses of inbred lines. One of the main applications of anther culture has been to produce diploid homozygous pure lines in a single generation, thus saving many generations of backcrossing to reach homozygosity by traditional means or in crops where self-pollination is not possible. Because doubled haploids are equivalent to inbred lines, their value has been appreciated by plant breeders for decades. The search for natural haploids and methods to induce them has been ongoing since the beginning of the 20th century."

Plant hormones play a crucial role in controlling the way in which plants growand develop. Whilemetabolism providesthepowerand buildingblocks for plant life, it is the hormones that regulate the speed of growth of the individual parts and integrate these parts to produce the form that we recognize as a plant. In addition, theyplayacontrolling role inthe processes of reproduction. This book is a description ofthese natural chemicals: how they are synthesizedand metabolized; howthey work; whatwe knowoftheir molecular biology; how we measure them; and a description ofsome ofthe roles they play in regulating plant growth and development. Emphasis has also been placed on the new findings on plant hormones deriving from the expanding use ofmolecular biology as a tool to understand these fascinating regulatory molecules. Even at the present time, when the role of genes in regulating all aspects of growth and development is considered of prime importance, it is still clear that the path of development is nonetheless very much under hormonal control, either via changes in hormone levels in response to changes in gene transcription, or with the hormones themselves as regulators ofgene transcription. This is not a conference proceedings, but a selected collection ofnewly written, integrated, illustrated reviews describing our knowledge of plant hormones, and the experimental work that is the foundation of this knowledge.

In a convenient, single-source reference, this book examines plant growth substances and their relationship to a wide range of physiological processes, ranging from seed germination through the death of the plant. If offers a clear illustration of the pragmatic uses of plant substances in agriculture and demonstrates how basic laboratory research has translated into increased production and profit for the grower. This work begins by building a solid foundation in the subject, which contains historical aspects and fundamental concepts, and provides a methodology for extraction, purification, and quantification of plant growth substances. This forms the basis for understanding the ensuing chapters that explore the many processes involving plant growth substances, including: * seed germination * seedling growth * rooting * dormancy * juvenility * maturity * senescence * flowering * abscission * fruit set * fruit growth * fruit development * premature drop * ripening * promotion of fruit drop * tuberization * photsynthesis * weed control. Providing a detailed examination of plant growth substances and their relationships to specific physiological plant processes, Plant Growth Substances gives students, researchers, and professionals a much needed reference.

Plant protoplasts have proved to be an excellent tool for in vitro manipu- lations, somatic hybridization, DNA uptake and genetic transformation, and for the induction of somaclonal variation. These studies reflect the far- reaching impact of protoplast alterations for agriculture and forest bio- technology. Taking these aspects into consideration, the series of books on Plant Protoplasts and Genetic Engineering provides a survey of the litera- ture, focusing on recent information and the state of the art in protoplast Plant Protoplasts manipulation and genetic transformation. This book, and Genetic Engineering VI, like the previous five volumes published in 1989,1993, and 1994, is unique in its approach. It comprises 27 chapters dealing with the regeneration of plants from protoplasts, and genetic transformation in various species of Arachis, Bupleurum, Capsella, Dendrobium, Dianthus, Diospyros, Fagopyrum, Festuca, Gentiana, Glycyrrhiza, Gossypium, Hemerocallis, Levisticum, Lonicera, Musa, Physallis, Platanus, Prunus, Saposhnikovia, Solanum, Spinacia, Trititrigia, Tulipa, and Vaccinium; including fruits such as apricot, banana, cranberry, pepino, peach, and plum. This book may be of special interest to advanced students, teachers, and research scientists in the field of plant tissue culture, molecular biology, genetic engineering, plant breeding, and general bio- technology. New Delhi, August 1995 Professor Y. P. S. BAJA] Series Editor Contents Section I Regeneration of Plants from Protoplasts 1. 1 Regeneration of Plants from Protop1asts of Arachis Species (Peanut) Z. LI, R. L. JARRET, and J. W. DEMSKI (With 2 Figures) 1 Introduction ...3 2 Isolation of Pro top lasts ...4 3 Culture of Protoplasts ...

This textbook contains the material for a course in the major principles of modelling crop growth processes. There is much more to crop growth than what is discussed in this textbook, but it provides a sound basis for further work and study in this field. Chapter by chapter the book leads the reader to different modelled aspects of crop growth, and at the end, the reader will have a good understanding of the Wageningen simulation model SUCROS for the potential production situation. By then, it will be much easier to find one's way through descriptions and listings of other models. Throughout the text, the study of the different topics is facilitated by exercises that support the course in a hands-on computer practical exercise. A very simple crop growth model, almost entirely based on radiation interception, is given first. This skeleton model is then expanded by submodels for respiration, carbon assimilation, plant development, and a more detailed model for radiation interception and reflection. Modelling of transpiration and the leaf energy balance is given by way of introduction. There are many listings of the submodels, written in the simulation language FST (FORTRAN Simulation Translator), as well as of SUCROS itself, together with plentiful comments. Some supporting theory is provided in the form of Appendices. The book is meant for students and scientists who would like to acquire a working knowledge of the technique of crop growth modelling.

Plant hormones play a crucial role in controlling the way in which plants growand develop. Whilemetabolism providesthepowerand buildingblocks for plant life, it is the hormones that regulate the speed of growth of the individual parts and integrate these parts to produce the form that we recognize as a plant. In addition, theyplayacontrolling role inthe processes of reproduction. This book is a description ofthese natural chemicals: how they are synthesizedand metabolized; howthey work; whatwe knowoftheir molecular biology; how we measure them; and a description ofsome ofthe roles they play in regulating plant growth and development. Emphasis has also been placed on the new findings on plant hormones deriving from the expanding use ofmolecular biology as a tool to understand these fascinating regulatory molecules. Even at the present time, when the role of genes in regulating all aspects of growth and development is considered of prime importance, it is still clear that the path of development is nonetheless very much under hormonal control, either via changes in hormone levels in response to changes in gene transcription, or with the hormones themselves as regulators ofgene transcription. This is not a conference proceedings, but a selected collection ofnewly written, integrated, illustrated reviews describing our knowledge of plant hormones, and the experimental work that is the foundation of this knowledge.

The quality of human life has been maintained and enhanced for generations by the use of trees and their products. In recent years, ever rising human population growth has put tremendous pressure on trees and tree products; growing awareness of the potential of previously un exploited tree resources and environmental pollution have both accelerated development of new technologies for tree propagation, breeding and improvement. Biotechnology of trees may be the answer to solve the problems which cannot be solved by conventional breeding methods. The combination of biotechnology and conventional methods such as plant propagation and breeding may be a novel approach to improving and multiplying in large number the trees and woody plants. So far, plant tissue culture technology has largely been exploited in the propagation of ornamental plants, especially foliage house plants, by com- mercial companies. Generally, tissue culture of woody plants has been recal- citrant. However, limited success has been achieved in tissue culture of angiosperm and gymnosperm woody plants. A number of recent reports on somatic embryogenesis in woody plants such as Norway spruce (Picea abies), Loblolly pine (Pinus taeda), Sandalwood (Santalum album), Citrus, Mango (Mangifera indica), etc. offer a ray of hope of: (a) inexpensive clonal propa- gation for large-scale production of plants or "emblings" or "somatic embryo plants"; (b) protoplast work; (c) cryopreservation; (d) genetic transforma- tion; and (e) artificial or manufactured seed production.

Automation and Environmental Control in Plant Tissue Culture rigorously explores the new challenges faced by modern plant tissue culture researchers and producers worldwide: issues of cost efficiency, automation, control, and optimization of the in vitro microenvironment. This book achieves a critical balance between the economic, engineering and biological viewpoints, and presents well-balanced, unique, and clearly organized perspectives on current initiatives in the tissue culture arena. Each chapter offers guidelines leading towards an exhaustive, unprecedented level of control over in vitro growth, based on emerging technologies of robotics, machine vision, environmental sensors and regulation, and systems analysis. Unlike other tissue culture books which focus on specific crops and techniques, this book spans the broad range of major tissue culture production systems, and advances evidence on how some underrated aspects of the process actually determine the status of the end product. Key researchers from industry and academia have joined to give up-to-date research evidence and analysis. The collection comprises an essential reference for industrial-scale tissue culture producers, as well as any researcher interested in optimizing in vitro production.

This book contains papers and posters presented at the 18th Eucarpia Fodder Crops Section Meeting held at Loen, Nordfjord, Norway in August 1993. In most environments some form of marginal conditions or stress prevails. Few crops are being produced under such a wide range of environmental and management stresses as fodder crops. Improved adaptation of fodder crops to marginal conditions is crucial in developing sustainable, low-input agricultural systems. The book is unique in demonstrating the large diversity both in crops and environmental stresses that confront the forage breeders. Both general and specific aspects of adaptation to marginal growing conditions are presented, ranging from problems caused by snow and ice in the Subarctic regions of Europe to the severe drought problems in the Mediterranean regions. For everyone involved in studies of adaptation and breeding of perennial plants for marginal conditions or stress environments.

In continuation of Volumes 8, 9, 22, and 23, this new volume deals with the regeneration of plants from isolated protoplasts and genetic transformation in various species of "Actinidia," "Allocasuarina," "Anthurium," "Antirrhinum," "Asparagus," "Beta," "Brassica," "Carica," "Casuarina," "Cyphomandra," "Eucalyptus," "Ipomoea," "Larix," "Limonium," "Liriodendron," "Malus," "Musa," "Physcomitrella," "Physalis," "Picea," "Rosa," "Tagetes," "Triticum," and "Ulmus."
These studies reflect the far-reaching implications of protoplast technology in genetic engineering of plants. The book contains a wealth of useful information for advanced students, teachers, and researchers in the field of plant tissue culture, molecular biology, genetic engineering, plant breeding, and general biotechnology.

Fantasies and dreams have their rightful place in science, and sometimes they turn into reality. Regeneration of hybrid plants through protoplast fusion is one such dream come true. In the early 1970s I shared the pioneering excitement in the field of protoplast technology at the Second International Congress of Plant Tissue Culture held in Strasbourg, France. Subsequently, I participated in three international conferences devoted to plant protoplasts, in Salamanca, Spain (1972), Versailles, France (1972), and Nottingham, England (1975). At Versailles Dr. P.S. Carlson presented his work on the successful regeneration of somatic hybrids between Nicotiana glauca and Nicotiana langsdorfii. The enthusi- asm shown by the participants was sufficient indication of the bright future of somatic hybridization. On my return from Versailles, I gathered my thoughts and prepared a concept paper on Potentials of Protoplast Culture Work in Agriculture which was published in Euphytica (Bajaj 1974). The studies on protoplast fusion and somatic hybridization then gained momentum and active work started in many laboratories. Very significant work was done by Melchers et al. (1978) who obtained a somatic hybrid between potato and tomato, calling it "Pomato".

This textbook contains the material for a course in the major principles of modelling crop growth processes. There is much more to crop growth than what is discussed in this textbook, but it provides a sound basis for further work and study in this field. Chapter by chapter the book leads the reader to different modelled aspects of crop growth, and at the end, the reader will have a good understanding of the Wageningen simulation model SUCROS for the potential production situation. By then, it will be much easier to find one's way through descriptions and listings of other models. Throughout the text, the study of the different topics is facilitated by exercises that support the course in a hands-on computer practical exercise. A very simple crop growth model, almost entirely based on radiation interception, is given first. This skeleton model is then expanded by submodels for respiration, carbon assimilation, plant development, and a more detailed model for radiation interception and reflection. Modelling of transpiration and the leaf energy balance is given by way of introduction. There are many listings of the submodels, written in the simulation language FST (FORTRAN Simulation Translator), as well as of SUCROS itself, together with plentiful comments. Some supporting theory is provided in the form of Appendices. The book is meant for students and scientists who would like to acquire a working knowledge of the technique of crop growth modelling.

In the past there were many attempts to change natural foodstuffs into high-value products. Cheese, bread, wine, and beer were pro duced, traditionally using microorganisms as biological tools. Later, people influenced the natural process of evolution by artificial selection. In the 19th century, observations regarding the depen dence of growth and reproduction on the nutrient supply led to the establishment of agricultural chemistry. Simultaneously, efforts were directed at defining the correlation between special forms of morphological differentiation and related biochemical processes. New experimental systems were developed after the discovery of phytohormones and their possible use as regulators of growth and differentiation. In these systems, intact plants or only parts of them are cultivated under axenic conditions. These methods, called "in vitro techniques," were introduced to modern plant breeding. In the field of basic research, plant cell cultures were increasingly developed and the correlations between biochemical processes and visible cell variations were explored further. It should be possible to manipulate the basic laws of regulation and the respective biochemi cal processes should be regarded as being independent of morpho logical processes of plant development."

Charles E. Hess Department of Environmental Horticulture University of California Davis, CA 95616 Research in the biology of adventitious root formation has a special place in science. It provides an excellent forum in which to pursue fundamental research on the regulation of plant growth and development. At the same time the results of the research have been quickly applied by commercial plant propagators, agronomists, foresters and horticulturists (see the chapter by Kovar and Kuchenbuch, by Ritchie, and by Davies and coworkers in this volume). In an era when there is great interest in speeding technology transfer, the experiences gained in research in adventitious root formation may provide useful examples for other areas of science. Interaction between the fundamental and the applied have been and continue to be facilitated by the establishment, in 1951, of the Plant Propagators' Society, which has evolved into the International Plant Propagators' Society, with active programs in six regions around the world. It is a unique organization which brings together researchers in universities, botanical gardens and arboreta, and commercial plant propagators. In this synergistic environment new knowledge is rapidly transferred and new ideas for fundamental research evolve from the presentations and discussions by experienced plant propagators. In the past 50 years, based on research related to the biology of adventitious root formation, advances in plant propagation have been made on two major fronts.

The symposium on "Zinc in Soils and Plants" is the third in a series which began with "Copper in Soils and Plants" in Perth in 1981 and continued with "Manganese in Soils and Plants" in Adelaide in 1988. The symP9sium brings together a series of valuable accounts of many aspects of the reactions of zinc in soils, the uptake, transport and utilization of zinc in plants, the diagnosis and correction of zinc deficiency in plants and the role of zinc in animal and human nutrition. I am grateful for the financial support provided by Grains Research and Development Corporation, Rural Industries Research and Development Corporation, Wool Research and Development Corporation, Ansett Australia, and Qantas Australian. I am most appreciative of the willingness of many scientists to act as referees: G S P Ritchie, R J Gilkes, N C Uren, K Tiller, BLeach, H Greenway, N E Longnecker, J F Loneragan, Z Rengel, C A Atkins, J W Gartrell, P J Randall, D G Edwards, R J Hannam, R J Moir, J E Dreosti, N Suttle, C L White, H Marschner, N Wilhelm, M McBride. All provided valuable comments on the manuscripts. Finally, I thank Mrs M Davison who provided excellent secretarial assistance. A.D. Robson September 1993 Chapter 1.