Research on the mechanisms of plant defense responses to stress and pathogen attack has attracted much attention in recent years. This increasing interest stems from the fact that the tools of molecular biology now enable us to study the molecular basis of old biological concepts such as host-pathogen recognition (and particularly the gene for-gene relationship), hypersensitive cell death and systemic acquired resistance. Our knowledge about avirulence and resistance genes, elicitors, signal transduction and genes involved in plant defense is rapidly expanding. Moreover we are just beginning to test in planta the potential of these results for biotechnological applications, aimed at improving plant resistance to diseases. The 2nd Conference of the European Foundation for Plant Pathology, hosted by the "Societe Fran~aise de Phytopathologie", was devoted to "Mechanisms of plant defense responses" and was held in Strasbourg, France. It brought together over 350 scientists from universities, research institutes and private sectors of 24 countries. Major advances in the areas under study have been reviewed in plenary lectures and are developed in the main articles of this book. Over 160 high-quality posters were presented and are summarized in short articles. Data from outstanding posters, which were discussed after a short oral presentation, are found in extended articles. As a whole the book presents a collection of papers arranged in six sections and reflecting the present day state-of-the-art of research in the field of plant defense reactions.

From February 24 -28, 1992 an international symposium on Durability of Disease Resistance was held at the International Agricultural Centre in Wageningen, the Netherlands. The symposium, organized by the Department of Plant Breeding of Wageningen Agricultural University and the Centre for Plant Breeding and Repro duction Research, CPRO-DLO, was part of the DGIS funded programme Durable Resistance in Developing Countries. Without any form of prevention or protection nearly all crops will be seriously or even severely damaged by a range of pathogens. In modern agriculture man has been able to control many if not most pathogens using i) pesticides, ii) phyto sanitary methods such as control of seed and plant material in order to start a crop disease free, iii) agronomic measures such as crop rotation, iv) disease resis tance or combinations of these measures. Over the years the use of pesticides has increased enormously and so did the pro blems associated with pesticide use, such as environmental pollution and building of resistance and tolerance to these pesticides in the pathogens. The use of resis tance too increased strongly over the years and here too problems arose.

Biological control offers a promising alternative to chemical control which can have adverse environmental implications. This volume contains 16 articles describing the most modern topics in biocontrol of plant pathogens, including risk analysis for the release of microbial antagonists, genetic engineering and application of tissue culture.

The molecular mechanisms which determine whether the cells of a multicellular organism will live or commit suicide have become a popular field of research in biology during the last decade. Cell death research in the plant field has also been expanding rapidly in the past 5 years. This special volume of Plant Molecular Biology seeks to bring together examples of a diverse array of experimental approaches in a single volume. From the differentiation of tracheary elements in vascular plants to the more specialized cell death model of the aleurone in cereals, this volume will bring the reader up-to-date with the characterization of different plant model systems that are currently being studied. This endeavor should complement general overviews of plant cell death mechanisms that have been published elsewhere by providing more detailed information on various aspects of this field to interested graduate students and more senior biologists alike.

During the last decade, research on Pseudomonas syringae pathovars and related pathogens has progressed rapidly, opening up many new avenues. The application of molecular genetics has provided new insights into determinants of pathogenicity and virulence. Progress has also been made in elucidating the chemical structures and modes of action of phytotoxins from Pseudomonas syringae; by establishing novel strategies for disease control; in biotechnological applications; by studying the resistant reaction of the plant with a combined biochemical and genetic approach; and in the development of new detection and identification methodologies as tools in epidemiological studies. With such rapid advances it becomes more and more difficult to keep abreast of the developments and concepts within disciplines, all involving research on pathovars of P. syringae. In an attempt to provide a balanced overview, recent developments in these rapidly expanding fields have been critically reviewed at the beginning of each chapter by internationally renowned experts. Our comprehensive coverage has been made possible because all the contributors to this volume presented their latest findings at the 5th International Conference on Pseudomonas syringae Pathovars and Related Pathogens' in Berlin, September 3-8, 1995. In this way, it was possible to bring together contributions from a wide range of fields including phytopathology, genetics, bacteriology, plant breeding, plant protection, and taxonomy. This book is not intended simply as a record of the proceedings of the Berlin Conference, but as an extension of recent findings and hypotheses put forward at the meeting. All papers published in this volume have been reviewed by the Editors.

When I received an invitation to attend the International Symposium on Lethal Yellowing being organised by the Centro de Investigacion Cientifica de Yucatan (CICy), I was excited and a little nostalgic. During the 1970s, a series of similar symposia had been held under the auspices of the loosely-constituted "International Council on Lethal Yellowing" (ICL Y). These were the years when the MLO cause for L Y was first proposed, a vector was found, the disease was racing across mainland Florida, USA and it was suspected of having jumped to Cozumel. Analogous diseases were also reported to be spreading in Africa and elsewhere. The ICL Y meetings, held approximately every two years, proved to be an immensely valuable forum for all involved in the research and control of L Y. They attracted a very wide cross-section of scientists and practitioners working on L Y, on related diseases, and on palms in general. Many participants of those ICL Y meetings also attended this CICY Symposium. Unfortunately, during the 1980s, as countries learned to live with L Y, most of the national and international funding for L Y research dried up, and so did ICL Y. The present symposium is the only international meeting to have been devoted to L Y since the last meeting of rCLY in 1979. Its convening in Merida is timely.

The fifth and last Volume of this IPMD series reviews, in a multi-disciplinary approach, recent achievements in crop protection and integrated management of arthropod pests. The volume is organized in a first Section covering IPM in citrus productions, a Second one dealing with advacements in the integratioon of management technologies and a last Section covering mites and their biological control agents. As for the previous volumes, we attempted to provide an informative coverage for a broad range of agricultural systems and situations. The chapters are mainly organized and centered on crops, with a particular emphasis on citrus. This is one of the main crops in which biological control and IPM approaches were tested successfully, and the experience gained herein may indeed result helpful for IMP efforts deployed worldwide on other crops and/or cropping systems. Chapters in Section 2 review the integration of insect and disease management options in pecan crops, the application of remote sensing technologies, the status of knowledge about plant defense compounds and their potentials. For IPM of invasive species, an update is provided on the experience gained on the Red Palm Weevil (RPW) in Egypt. Long-term technological solutions for IPM in forests and park areas through aerial treatments with Bt spores concludes this Section. Finally, in Section 3, updated reviews about biological control agents of mites are provided.

The protection of agricultural crops, forest, and man and his domestic animals from annoyance and damage by various kinds of pests remains a chronic problem. As we endeavor to improve pro duction processes and to develop more effective and acceptable tactics for achieving this protection, we must give high priority to all potentially useful techniques for the control and management of insects. Pest control is recognized as an acceptable and necessary part of modern agriculture. Methods employed vary greatly and tend to reflect compromises involving 3 determining factors: technological capability, economic feasibility, and social acceptability. How ever, these factors are also subject to change with time since each involves value judgments that are based on available information, cost, benefit considerations, the seriousness of the pest problem, and the political climate. Whatever method is chosen, energy resources continue to dwindle under the impact of increasing popu lation, and it is inevitable that greater reliance must be placed upon renewable resources in pest management. One alternative is the use of a pest management method that uses the energy of the pest's own biomass to fuel a self-perpetuating control system. The use of biological control agents for the control of pests has long been an integral part of the pest management strategy in crop production and forestry and in the protection of man and animals. The importance and unique advantages of the method are well recognized; numerous treatises deal with accomplishments and methodologies."

The Fruits and Vegetables manual is a reference manual on diseases which attack fruits (including berries), vegetables, and nuts. The manual identifies various types of diseases which are known to invade these plants located throughout North, Central, and South America. The recordings include diseases caused by fungi, bacteria, viruses, viroids, phytoplasmas, and nematodes. Causal disease agents are described and illustrated in some cases and diseases and disease control measures are also discussed. A manual such as this is never finished since new reports of diseases are continuously reported.

The Trees and Shrubs manual is a reference manual on diseases which attack trees, shrubs, and vines. The manual identifies various types of diseases which are known to invade these plants located throughout North, Central, and South America. The recordings include diseases caused by fungi, bacteria, viruses, viroids, phytoplasmas, and nematodes. Causal disease agents are described and illustrated in some cases and diseases and disease control measures are also discussed. A manual such as this is never finished since new reports of diseases are continuously reported.

The Garden and Greenhouse Flowers manual is a reference manual on diseases which attack garden and greenhouse flowers. The manual identifies various types of diseases which are known to invade these plants located throughout North, Central, and South America.The recordings include diseases caused by fungi, bacteria, viruses, viroids, phytoplasmas, and nematodes. Causal disease agents are described and illustrated in some cases and diseases and disease control measures are also discussed. A manual such as this is never finished since new reports of diseases are continuously reported.

The Grasses and Native Plants manual is a reference manual on diseases which attack grasses, forage, native flowers, and weeds. The manual identifies various types of diseases which are known to invade these plants located throughout North, Central, and South America. The recordings include diseases caused by fungi, bacteria, viruses, viroids, phytoplasmas, and nematodes. Causal disease agents are described and illustrated in some cases and diseases and disease control measures are also discussed. A manual such as this is never finished since new reports of diseases are continuously reported.

Abstract This chapter defines food security as the condition reached when a nation's population has access to sufficient, safe, and nutritious food to meet its dietary needs and food preferences. It stresses China's importance to global food security because of its population size. The chapter introduces the contents of the volume and then treats briefly food security in ancient and dynastic (211 bc-1912) China. It examines environmental stressors, such as population growth, natural disasters, and insect pests as well as imperial responses (for example, irrigation, flood control, storage and transportation systems). The chapter also briefly int- duces the Republican era (1912-1949) and compares environmental stressors and government responses then to those of the imperial period. Keywords Food system * Food security * Food production regions * Environmental stressors (Population growth * Natural disasters * Insect pests and Plant diseases * Deforestation * Climate change) * Irrigation systems * Flood control * Grand Canal 1. 1 The Problem of Food Security and Environmental Change Food is the material basis to human survival, and in each nation-state, providing a system for the development, production, and distribution of food and its security is a primary national objective. Many forces have influenced the food security of peoples since ancient times, with particular challenges from natural disasters (floods, famines, drought, and pestilence) and growing populations globally.

This book contains fuller versions of the papers and posters presented in the Knowledge and Technology Transfer and Teaching Plant Pathology sessions at the 9th International Congress of Plant Pathology held in Turin, Italy in 2008. Communication is an essential area for plant pathologists and it is not just the publication of results in the scientific press that is important. In a world where there is a major shortage of food and where a significant amount of it is destroyed by pests and diseases before it ever reaches the consumer, it is important to provide support to those who produce the food in order to reduce the losses. Reducing crop losses not only has an impact on health, but also wealth and, therefore, the ability to survive. With an ever-increasing demand on food supplies due to increases in population, and changes in life-style associated with rising incomes in certain parts of the world, plant pathologists have a pivotal role to play in contributing to global food security. Aspects of crop protection have lost favour with the general public because of concerns about environmental pollution and genetic modification of crops. This has had a 'knock on' effect in the recruitment and training of crop protectionist in g- eral and a concomitant impact on courses available at universities. However, it has never been more important to train people with good communication skills and an ability to solve problems to tackle the complexities of pathogen and plant interactions.

Genetics and Genomics of Populus provides an indepth description of the genetic and genomic tools and approaches for Populus, examines the biology that has been elucidated using genomics, and looks to the future of this unique model plant. This volume is designed to serve both experienced Populus researchers and newcomers to the field. Contributors to the volume are a blend of researchers, some who have spent most of their research career on Populus and others that have moved to Populus from other model systems. Research on Populus forms a useful complement to research on Arabidopsis. In fact, many plant species found in nature are - in terms of the life history and genetics - more similar to Populus than to Arabidopsis. Thus, the genetic and genomic strategies and tools developed by the Populus community, and showcased in this volume, will hopefully provide inspiration for researchers working in other, less well developed, systems.

This collection of papers represents some of those given at the International Congress for Plant Pathology held in Turin in 2008 in the session with the title "The Role of Plant Pathology in Food Safety and Food Security". Although food safety in terms of "Is this food safe to eat?" did not receive much direct attention it is, never theless, an important topic. A crop may not be safe to eat because of its inh- ent qualities. Cassava, for example, is cyanogenic, and must be carefully prepared if toxicosis is to be avoided. Other crops may be safe to eat providing they are not infected or infested by microorganisms. Mycotoxins are notorious examples of compounds which may contaminate a crop either pre- or post-harvest owing to the growth of fungi. Two papers in this book deal with toxins, one by Barbara Howlett and co-workers and the other by Robert Proctor and co-workers. In the first of these, the role of sirodesmin PL, a compound produced by Leptosphaeria ma- lans, causal agent of blackleg disease of oilseed rape (Brassica napus), is discussed. The authors conclude that the toxin plays a role in virulence of the fungus and may also be beneficial in protecting the pathogen from other competing micro-organisms but there seem to be no reports of its mammalian toxicity.

Plants live in a constantly changing environment from which they cannot physically escape. Plants therefore need signalling and response mechanisms to adapt to new local conditions. The ef?cacy of such mechanisms underlies the plant performance during stress and therefore also impacts greatly on agricultural productivity. M- ulation of ion channel activity not only provides a means for rapid signal generation 2+ but also allows adjustment of cellular physiology. For example, Ca permeable ion 2+ channels can transduce environmental stimuli into Ca -encoded messages which can modify the gene expression. Furthermore, ion channel activity is essential to control cellular ion homeostasis that impacts on plant responses to drought, salinity, pathogens, nutrient de?ciency, heavy metals, xenobiotics and other stresses. This volume focuses on the crucial roles of different types of ion channel in plant stress responses. Functions of ion channels are discussed in the context of mechanisms to relay external and endogenous signals during stress and as mechanisms to regulate cellular ion homeostasis and enzymatic activities in the context of biotic and abiotic stress. The chapters presented cover cation and anion channels located in various cellular compartments and tissues.

Only 14 years have passed since the first publication appeared which implicated mycoplasmas as agents of plant disease. The diseases them selves have been known for much longer; indeed clover phyllody, a typical example, was described in the seventeenth century, well before any animal mycoplasma diseases had been documented. The early history of plant mycoplasmas is described in Chapter 2 and one obvious conclusion to be drawn from the frustrating experiences of the earlier workers is that the experimental methods at their disposal were simply inadequate for the task. Progress in science depends critically upon the development of new methods. Although important advances have been made in plant and insect mycoplasmology, notably in the discovery of spiroplasmas, many intractable problems remain. Most plant myco plasmas cannot yet be cultured in vitro, and their natural plant habitat, the phloem, is one of the most difficult plant tissues for the experi menter to handle, placing severe restrictions on the type of experiments which can be performed in vivo. It is clear that radically new methods may be required to solve these problems. A survey of the progress which has been made shows that application of techniques from a wide range of disciplines has been necessary. A successful individual or group of workers must possess the skills of a plant pathologist, a plantsman, a plant physiologist, a light-and electron microscopist, a bacteriologist, a biochemist, an immunologist, an ento mologist, a virologist and a molecular geneticist."

It was a compliment to me to be asked to prepare the fourth edition of Westcott's Plant Disease Handbook, and the decision to accept the responsi bility for the fourth edition and now the fifth edition was not taken lightly. The task has been a formidable one. I have always had a great respect professionally for Dr. Cynthia Westcott. That respect has grown considerably with the completion of the two editions. I now fully realize the tremendous amount of effort expended by Dr. Westcott in developing the Handbook. A book such as this is never finished, since one is never sure that everything has been included that should be. I would quote and endorse the words of Dr. Westcott in her preface to the first edition: "It is easy enough to start a book on plant disease. It is impossible to finish it. " This revision of the Handbook retains the same general format contained in the previous editions. The chemicals and pesticides regulations have been updated; a few taxonomic changes have been made in the bacteria, fungi, and mistletoes; the changing picture in diseases caused by viruses and/or viruslike agents has been described. A few new host plants have been added, and many recently reported diseases as well as previously known diseases listed now on new hosts have been included. In addition, photographs have been replaced where possible, and the color photograph section has been retained.

The past decade is probably unparalleled as a period of dynamic changes in the crop protection sciences-entomology, plant pathology, and weed science. These changes have been stimulated by the broad-based concern for a quality environment, by the hazard of intensified pest damage to our food and fiber production systems, by the inadequacies and spiraling costs of conventional crop protection programs, by the toxicological hazards of unwise pesticide usage, and by the negative interactions of independent and often narrowly based crop protection practices. During this period, the return to ecological approaches in crop protection was widely accepted, first within entomology and ultimately within the other crop protection and related disciplines. Integrated pest management is fast becoming accepted as the rubric describing a crop pro tection system that integrates methodologies across all crop protection dis ciplines in a fashion that is compatible with the crop production system. Much has been written and spoken about "integrated control" and "pest management," but to date no treatise has been devoted to the concept of "in tegrated pest management" in the broadened context as described above. Most of the manuscripts in this volume were developed from papers presented in a symposium at the annual meeting of the American Association for the Ad vancement of Science held in San Francisco in February, 1974. In arranging that symposium, the editors involved plant pathologists, entomologists, and weed scientists."

Pesticides have played a significant role in increasing food production, and in view of growing worldwide food demand we can expect the use of these chemicals to increase. However, some of them have found their way into the biosphere and have been classi fied as persistent toxic chemicals. This has resulted in serious concern about environmental contamination. Since we are going to continue using chemicals, we should learn more about such aspects as their transport in the environment, the relationship of their physical-chemical properties to transport, their persistence in the biosphere, their partitioning in the biota, and toxicological and epidemiological forecasting based on physical-chemical properties. Environmental chemodynamics is the name given to a subject which deals with some of the above topics, utilizing the principles of such disciplines as chemistry, physics, systems analysis, modelling, engineering, and medical and biological sciences. To ensure the safety of the environment, we must know more about the chemodynamical behavior of pesticides and related chemi cals. The purpose of the symposium "Environmental Dynamics of Pes ticides" was to explore the concept of chemodynamics as applied to pesticides and thus may help in developing the emerging field of environmental chemodynamics. The symposium was held during the l37th National American Chemical Society Meeting at Los Angeles, California, during April, 1974. The three sessions in the sym posium were chai'red by Drs. V.H. Freed, D.G. Crosby, and R. Haque."

As a collection of papers that includes material presented at the 2008 International Congress for Plant Pathology, this text features research right at the leading edge of the field. The latest findings are particularly crucial in their implications for fruit production; an important market sector where in some areas up to 50 per cent of the crop can be lost after harvest. While post-harvest fruit treatments with fungicides are the most effective means to reduce decay, rising concerns about toxicity have led to the development of alternative approaches to disease control, including biological methods, the subject of three chapters of this book. With several new techniques requiring modification of current post-harvest practices, it is more important than ever to stay abreast of the latest information. Other chapters deal with the mechanisms of host fruit and vegetable resistance, fungal pathogenicity factors and their relationship with the host response, and a number of subjects related to disease assessments before harvest as well as their relationship to the postharvest treatment of fruits and vegetables. The book also includes several useful case studies of crops such as kiwifruit and peaches, where different approaches at the pre- and post-harvest levels are combined to good effect. With food production issues gaining an ever higher profile internationally, this text makes an important contribution to the debate.

The future of agriculture greatly depends on our ability to enhance productivity without sacrificing long-term production potential. The application of microorganisms, such as the diverse bacterial species of plant growth promoting bacteria (PGPB), represents an ecologically and economically sustainable strategy. The use of these bio-resources for the enhancement of crop productivity is gaining importance worldwide. "Bacteria in Agrobiology: Disease Management" discusses various aspects of biological control and disease suppression using bacteria. Topics covered include: fluorescent pseudomonads; siderophore-producing PGPR; pseudomonas inoculants; bacillus-based biocontrol agents; bacterial control of root and tuber crop diseases; fungal pathogens of cereals; soil-borne fungal pathogens; peronosporomycete phytopathogens; and plant parasitic nematodes.

Seeds provide an efficient means in disseminating plant virus and viroid diseases. The success of modern agriculture depends on pathogen free seed with high yielding character and in turn disease management. There is a serious scientific concern about the transmission of plant viruses sexually through seed and asexually through plant propagules. The present book provides the latest information along with the total list of seed transmitted virus and viroid diseases at global level including, the yield losses, diagnostic techniques, mechanism of seed transmission, epidemiology and virus disease management aspects. Additional information is also provided on the transmission of plant virus and virus-like diseases through vegetative propagules. It is also well known that seed transmitted viruses are introduced into new countries and continents during large-scale traffic movements through infected germplasm and plant propogules. The latest diagnostic molecular techniques in different virus-host combinations along with disease management measures have been included. The book shall be a good reference source and also a text book to the research scientists, teachers, students of plant pathology, agriculture, horticulture, life sciences, green house managers, professional entrepreneurs, persons involved in quarantines and seed companies. This book has several important features of seed transmitted virus diseases and is a good informative source and thus deserves a place in almost all university libraries, seed companies and research organizations.

The development of resistance to pesticides is generally acknowledged as one of the most serious obstacles to effective pest control today. Since house flies first developed resistance to DDT in 1946, more than 428 species of arthropods, at least 91 species of plant pathogens, five species of noxious weeds and two species of nematodes were reported to have developed strains resistant to on or more pesticides. A seminar of U. S. and Japanese scientists was held in Palm Springs, California, during December 3-7, 1979, under the U. S. -Japan Cooperative Science Program, in order to evaluate the status of research on resistance and to discuss directions for future emphasis. A total of 32 papers were presented under three principal topics: Origins and Dynamics of Resistance (6), Mechanisms of Resistance (18), and Suppression and Management of Resistance (8). The seminar was unique in that it brought together for the first time researchers from the disciplines of entomology, plant pathology and weed science for a comprehensive discussion of this common problem. Significant advances have been identified in (a) the development of methods for detection and monitoring of resistance in arthropods (electrophoresis, diagnostic dosage tests) and plant pathogens, (b) research on biochemical and physiological mechanisms of resis tance (cytochrome p450, sensitivity of target site, gene regulation), (c) the identification and quantification of biotic, genetic and operational factors influencing the evolution of resistance, and (d) the exploration of pest management approaches incorporating resis tance-delaying measures."