P. T. N. SPENCER-PHILLIPS Co-ordinator, Downy Mildew Working Group of the International Society for Plant Pathology University of the West of England, Coldharbour Lane, Bristol BS16 1QY, UK Email: [email protected] It is a very great privilege to write the preface to the first specialist book on downy mildews since the major work edited by D. M. Spencer in 1981. The idea for the present publication arose from the Downy Mildew Workshop at the International Congress of Plant Pathology (ICPP) held in Edinburgh in August 1998. Our intention was to invite reviews on selected aspects of downy mildew biology from international authorities, and link these to a series of related short contributions reporting new data. No attempt has been made to cover the breadth of downy mildew research, but we hope that further topics will be included in future volumes, so that this becomes the first of a series following the five year ICPP cycle.

The growing body of information on bacteria pathogenic for humans, mammals and plants generated within the past ten years has shown the interesting conservation of newly identified genes that playa direct role in the pathogenic mechanism. In addition to these genes, there are also genes that confer host specificities and other traits important in pathogenesis on these pathogens. In this volume, we have organized the subject areas to best fit the concept on the way bacterial pathogens recognize, interact and invade the host, on the regulation of genes involved in virulence, on the genes involved in the elaboration of toxins and other pathogenic components such as iron sequestering proteins, and on the mechanisms of circumventing the host defense systems. These areas are divided into Sections. Section I covers the first step when the pathogen seeks its host, and Sections II through VI cover subsequent steps leading to pathogenesis while avoiding host defenses. We conclude this work with a chapter summarizing information on examples of virulence mechanisms that are highly conserved.

Plant disease management remains an important component of plant pathology and is more complex today than ever before including new innovation in diagnostic kits, the discovery of new modes of action of chemicals with low environmental impact, biological control agents with reliable and persistent activity, as well as the development of new plant varieties with durable disease resistance. This book is a collection of invited lectures given at the 9th International Congress of Plant Pathology (ICPP 2008), held in Torino, August 24-29, 2008 and is part of a series of volumes on Plant Pathology in the 21st Century. It focuses on new developments of disease management and provides an updated overview of the state of the art given by world experts in the different fields of disease management. The different chapters deal with basic aspects of disease management, mechanisms of action of biological control agents, innovation in fungicide application, exploitation of natural compounds and resistance strategies. Moreover, the management of soil-borne diseases and disease management in organic farming are covered.

Perhaps the best expression of our intent in organ z ng this gathering is found in the definition of the word colloquy and its derivations. A gathering allowing familiar and informal conversation among colleagues with similar interests was our objective. Our motives were, of course, complex. Our main intent was not, however, to add to the list of books competing for the time of the scientific community at-large. However, while informality was our objective, a lasting document exists in the form of this publication of the presentations forming the skeleton on which we built less formal but meatier communications. We hope you can reconstruct on these bones a perception of the state of the art in the subject at hand. The members of this assemblage are specialists in one or more subdisciplines. Their formal communications are found in texts and journals appropriate to their broader disciplines. Often their friends alone are privy to their less formal thoughts, intuitions, hopes, and especially fears and failures. We hoped by organizing this colloquium to develop familiar and informal conversation among those most interested and active in applying semiochemicals in pest control. That community, like others also shared by Gainesville entomologists, has little or no formal organization or means for assemblage. We proposed on this and future occasions to offer the opportunity to this and similar groups to gather, though we do not presume too much to lead but rather to facilitate conversation.

Pest Management Programs for Deciduous Tree Fruits and Nuts attempts to present the current status of pest management programs in orchard ecosystems. The book is a collection of papers from a symposium convened on the subject for the 1977 National Meeting of the Entomological Society of America and invitational papers on commodities not covered during the symposium. In recent years, books have appeared on "integrated pest management (IPM)"; however, most of these have concentrated on field crop IPM with an occasional chapter on fruits. No publication presently exists which brings together information on the pest management programs currently being conducted on the major nut crops, almonds, pecans and walnuts. Because it is the first treatment for almonds and walnuts, the authors of these chapters have attempted not only to present the current IPM technology but the historical data which led to the contemporary programs. Two chapters appear on pecan IPM. The first concentrates on the development of a management program for the pecan weevil, the key arthropod pest of pecans, while the second discusses the implementation of pilot pecan IPM programs in two southeastern states. The latter chapter illustrates that even with a limited data bank, the pesticide load in pecan orchards can be reduced by the adoption of the IPM approach to pest control.

Experience shows that biotic stresses occur with different levels of intensity in nearly all agricultural areas around the world. The occurrence of insects, weeds and diseases caused by fungi, bacteria or viruses may not be relevant in a specific year but they usually harm yield in most years. Global warming has shifted the paradigm of biotic stresses in most growing areas, especially in the tropical countries, sparking intense discussions in scientific forums. This book was written with the idea of collecting in a single publication the most recent advances and discoveries concerning breeding for biotic stresses, covering all major classes of biotic challenges to agriculture and food production. Accordingly, it presents the state-of-the-art in plant stresses caused by all microorganisms, weeds and insects and how to breed for them. Complementing Plant Breeding for Abiotic Stress Tolerance, this book was written for scientists and students interested in learning how to breed for biotic stress scenarios, allowing them to develop a greater understanding of the basic mechanisms of resistance to biotic stresses and develop resistant cultivars.

More than 270 scientists from 33 countries attended the 6th International Conference on Plant Pathogenic Bacteria in College Park, Maryland, June 2-7, 1985. The Conference was jOintly sponsored by the International Society of Plant Pathology, Bacteria Section and by the United States Department of Agriculture, Agriculture Research Service. The Conference provided an opportunity for the presentation and discussion of recent developments in phytobacteriology. The Conference was organized into five symposia, seven discussion sessions, contributed papers and poster presentations. More than 230 contributions were presented under the following topics: ice nucleating bacteria; detection, identification, nomenclature and taxonomy of phytopathogenic bacteria; applications and impact of new biotechnologies on phytobacteriology; bacterial phytotoxins; diagnostic phytobacteriology; management of bacterial plant diseases; and molecular biology, genetics and ecology, epidemiology of phytopathogenic bacteria. In addition, special sessions focused on Agrobacterium, Erwinia, Psedomonas and fastidious prokaryotes. This reflected the broad spectrum of current research activity in phytobacteriology. Furthermore, interest in this series of conferences clearly continues to increase. Key research scientists who are currently making major advances in phytobacteriology participated in the Symposia and Discussions. One of the most significant recent changes that has occurred in the field of plant pathology generally is the dynamic growth of research in which recombinant DNA technology is being applied in basic studies on bacterial plant pathogens. Results from investigations on the crown gall bacterium have stimulated expansion of research on other bacterial systems.

Allelopathy is an ecological phenomenon by which plants release organic chemicals (allelochemicals) into the environment influencing the growth and survival of other organisms. In this book, leading scientists in the field synthesize latest developments in allelopathy research with a special emphasis on its application in sustainable agriculture. The following topics are highlighted: Ecological implications, such as the role of allelopathy during the invasion of alien plant species; regional experiences with the application of allelopathy in agricultural systems and pest management; the use of microscopy for modeling allelopathy; allelopathy and abiotic stress tolerance; host allelopathy and arbuscular mycorrhizal fungi; allelopathic interaction with plant nutrition; and the molecular mechanisms of allelopathy. This book is an invaluable source of information for scientists, teachers and advanced students in the fields of plant physiology, agriculture, ecology, environmental sciences, and molecular biology.

Plants use resources, i.e. carbon, nutrients, water and energy, either for growth or to defend themselves from biotic and abiotic stresses. This volume provides a timely understanding of resource allocation and its regulation in plants, linking the molecular with biochemical and physiological-level processes. Ecological scenarios covered include competitors, pathogens, herbivores, mycorrhizae, soil microorganisms, carbon dioxide/ozone regimes, nitrogen and light availabilities. The validity of the Growth-Differentiation Balance Hypothesis is examined and novel theoretical concepts and approaches to modelling plant resource allocation are discussed. The results presented can be applied in plant breeding and engineering, as well as in resource-efficient stand management in agriculture and forestry.

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There is suf?cient need to document all the available data on biological control of rice diseases in a small volume. Part of this need rests on the global importance of rice to human life. In the ?rst chapter, I have tried to show that rice is indeed life for most people in Asia and shortages in production and availability can lead to a food crisis. While rice is cultivated in most continents, biological disease management attains special relevance to rice farmers of Africa, Asia, and also perhaps, Latin America. These farmers are resource-poor and might not be able to afford the cost of expensive chemical treatments to control devastating rice pathogens such as Magnaporthe oryzae (blast), Xanthomonas oryzae pv. oryzae (bacterial leaf blight), Rhizoctonia solani (sheath blight) and the virus, rice tungro disease. In an earlier volume that I developed under the title, Biological Control of Crop Diseases (Dekker/CRC Publishers, 2002), I included transgenic crops generated for the management of plant pathogens as biological control under the umbrella of a broad de?nition. Dr Jim Cook who wrote the Foreword for the volume lauded the inclusion of transgenic crops and induced systemic resistance (ISR) as a positive trend toward acceptance of host plant resistance as part of biocontrol. I continue to subscribe to this view.

Plant pathology embraces all aspects of biological and scientific activity which are concerned with understanding the complex phenomena of diseases in plants. Physiological plant pathology represents those specialities within plant pathology which focus on the physiological and biochemical activities of pathogens and on the response of host plant tissues. Today there is an increasing recognition on the part of the scientific agri cultural community that only through a deeper and more fundamental under standing of all the interacting components of the agricultural biota can we expect to improve our capabilities of feeding an expanding world population. It is in this context that physiological plant pathology has assumed new significance within the broader field of plant pathology. No longer are studies on the biochemistry and physiology of pathogens and pathogenesis merely isolated academic exercises; rather, a substantial coherent body of knowledge is accumulating upon which our understanding of the process of disease developmen t and host resistance is being founded. It is from these foundations of knowledge that ultimately new insights into the control of plant diseases may be expected to grow. It seems appropriate, therefore, that at regular intervals those involved in the various subspecialities encompassing the broadest aspects of physiological plant pathology reassess the contributions within the particular specialities in the light of new knowledge and technologies for the purpose of articulating new and productive directions for the future."

Plant growth and development is controlled by various environmental cues that are sensed by the plant via various signal transduction pathways coupled to specific response. Some of these pathways are conserved from yeast to plants being regulated by various kinases and phosphatases. In addition, plants have many unique pathways that transduce to specific signals such as light, phytohormones and oligosaccharides. This volume highlights some of the examples of the plant signal transduction machinery opening new vistas in research on plant growth and development. The new technologies including the use of bacteria, yeast and Arabidopsis as functional complementation systems are providing proof of function of many of the proteins that show homology to those from other organisms. These studies will eventually lead to improvement of crop plants and use of plants as a new resource for producing desirable products to meet the growing needs of mankind.

Proceedings of a Meeting of the IUFRO, Working Party on Root Physiology and Symbiosis

The Proceedings of the 4th International Symposium held by the European Foundation for Plant Pathology on Diagnosis and Identification of Plant Pathogens in Bonn, Germany, from September 9th to 12th, 1996, include information on the application of classical as well as novel and innovative methods and techniques. This book gives an overview of the recent status and trends in the diagnosis and identification of viruses, bacteria and fungi in plants. It covers not only the development of methods and application of techniques but also its transformation into practice for disease-forecasting systems. The book includes 58 oral presentations and 61 poster contributions covering 6 main topics. In addition to introductory overviews of the phytosanitary implications of diagnosis in integrated crop protection, the application of classical and innovative diagnostic methods is stressed. The other contributions cover taxonomy and differentiation of plant pathogens, serological assays, nucleic acid based hybridisation techniques, disease assessment and quantification as well as disease prognosis and expert systems. This book provides information for all researchers and scientists involved in the production of healthy crop plants. It is of special interest for plant pathologists with responsibilities in the fields of plant quarantine, extension and applied diagnosis of plant pathogens as well as for those working in research and development of innovative crop protection techniques.

Plants interact with a large number of microoganisms which have a major impact on their growth either by establishing mutually beneficial symbiotic relationships or by developing as pathogens at the expense of the plant with deleterious effects. These microorganisms differ greatly not only in their nature (viruses, phytoplasmas, bacteria, fungi, nematodes, ... ) but also in the way they contact, penetrate and invade their host. Histology and cytology have brought an essential contribution to our knowledge of these phenomena. They have told us for instance, how specialized structures of the pathogen are often involved in the adhesion and penetration into the plant, how the interface between both organisms is finely arranged at the cellular level, or what structural alterations affect the infected tissues. They have thus set the stage for the investigations of the underlying molecular mechanisms could be undertaken. Such investigations have been remarkably successful in the recent years, expanding considerably our understanding of plant-microorganism interactions in terms of biochemical changes, rapid modifications of enzymatic activities, coordinated gene activation, signal reception and transduction. Biochemistry, molecular biology and cellular physiology have taken precedence in the phytopathologist's set of methods.

Studies related to pathogen-mediated virus resistance in plants were instrumental in providing some of the historical observations which ultimately led to the vital discovery of double-stranded RNA (dsRNA)-induced gene silencing or RNA interference (RNAi), which has since revolutionized research on plant-virus interactions. In Antiviral Resistance in Plants: Methods and Protocols, expert researchers in the field detail many of the methods which are now commonly used to study the phenomenon of RNA silencing in relation to viral infections of plants. These include methods and techniques for the isolation and quantitative/qualitative analyses of plant small 21-24 nucleotide RNAs such as small interfering RNAs (siRNAs) and microRNAs (miRNAs) as well as the analysis and manipulation of virus-induced gene silencing (VIGS) in both monocotyledonous and dicotyledenous plants and the use of hairpin RNA (hpRNA) transgenes. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and key tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Antiviral Resistance in Plants: Methods and Protocols seeks to aid scientists in the further study of this crucially important botanical trait.

The fifth meeting of scientists working with Frankia and actinorhizal plants was held at Montmorency Forest of Laval University in Quebec from August 6-8, 1984. Results of research presented at the meeting are included in this special volume of Plant and Soil. The understanding of actinorhizal systems continue to increase, though work and use shops and discussions at this and similar meetings make it evident that this important subject remains open for fruitful investigation at all levels. Some important 'firsts' were reported at this meeting. The first extensive survey of Frankiae and their host specificity ranges from Asia was presented. This is of significance since Asia is a center of diversity for many actinorhizal host plant genera. A report that proto plasts of Frankia have been produced and regenerated for the first time improves the possibility for genetic manipulation of Frankia. It is also important to note the first report herein of successful mass inoculation of actinorhizal plants commercially for stabilization and reclamation of disturbed soils around hydroelectric power projects in Quebec. This heralds the transfer of actinorhizal technology to private and public users. The bacterial genus Frankia is easily recognized both in vivo and in vitro, and isolation of this organism has become routine. But, as yet, there are not sufficient biochemical, morphological, or anatomical criteria for establishing species."

Precise regulation of gene expression in both time and space is vital to plant growth, development and adaptation to biotic and abiotic stress conditions. This is achieved by multiple mechanisms, with perhaps the most important control being exerted at the level of transcription. However, with the recent discovery of microRNAs another ubiquitous mode of gene regulation that occurs at the post-transcriptional level has been identified. MicroRNAs can silence gene expression by targeting complementary or partially complementary mRNAs for degradation or translational inhibition. Recent studies have revealed that microRNAs play fundamental roles in plant growth and development, as well as in adaptation to biotic and abiotic stresses. This book highlights the roles of individual miRNAs that control and regulate diverse aspects of plant processes.

Microorganisms, including those genetically modified (GMOs), are increasingly being released deliberately into the environment for different purposes. One major interest is the use of antagonistic organisms for biological control of pests and plant diseases. Both in the development of biocontrol agents and their later risk assessment and product approval, there is a need for methods that facilitate monitoring of such introduced microorganisms. This book particularly addresses the various approaches for monitoring introduced fungi and the current status of techniques which may be relevant to use are described. Such techniques include marker genes and other DNA-based techniques, serology using polyclonals or monoclonals, the use of enzymes or secondary metabolite profiles, and electronic noses' as well as more traditional methods like dilution plating.

Large parts of the continents are covered by a green blanket of living plants. From an insect's point of view this green blanket is not uniform, but consists of a mosaic of resources of variable quality and with various levels of noxious secondary compounds. It is the challenge of phytophagous insects to orientate and reproduce within this mosaic of resources and among hostile competitors and natural enemies. The International Symposia on Insect-Plant Relationships (SIP) provides fora where scientists from different fields (mainly in biology and chemistry) meet and discuss the most recent findings which contribute to our understanding of the complex interactions between plants and insects. The meetings seek to unravel basic mechanisms as well as applied aspects. It is recognized that human activities now have major influence on virtually all the world's ecosystems, and a better understanding of the dynamics of insect-plant interactions may be useful for development of new crop protection strategies and for coping with the threatening loss of biodiversity.

The 11th International Symposium on Insect-Plant Relationships (SIP11), held on August 4-10, 2001, in Helsingor, Denmark, followed the tradition of previous SIP meetings and covered topics of different levels from chemistry, physiology, and ethology to ecology, genetics, and evolution of insect-plant relationships. The present volume includes a representative selection of fully refereed papers as well as a complete list of all the contributions which were presented at the meeting. Reviews of selected topics as well as original experimental data are included. The book provides valuable information for students and research workers interested in chemical and biological aspects of interactions between individuals and populations of different organisms. "

To meet the challenge of feeding ever increasing human population, efficient, economical and environment friendly disease control methods are required. Pests are responsible for heavy crop losses and reduced food supplies, poorer quality of agricultural products, economic hardship for growers and processor. Generally, chemical control methods are neither always economical nor are they effective and may have associated unwanted health, safety and environmental risks. Biological control involves use of beneficial microorganism to control plant pathogens and diseases they cause and offers an environmental friendly approach to the effective management of plant diseases. This book provides a comprehensive account of interaction of host and its pathogens, induced host resistance, development of biological control agents for practical applications, the underlying mechanism and signal transduction. The book is useful to all those working in academia or industry related to crop protection.

Research on the interactions of plants and phytopathogenic fungi has become one of the most interesting and rapidly moving fields in the plant sciences, the findings of which have contributed tremendously to the development of new strategies of plant protection. This book offers insight into the state of present knowledge. Special emphasis is placed on recognition phenomena between plants and fungi, parasitization strategies employed by the phytopathogenic fungi, the action of phytotoxins, the compatibility of pathogens with host plants and the basic resistance of non-host plants as well as cultivar-specific resistance of host plants. Special attention is paid to the gene-for-gene hypothesis for the determination of race-specific resistance, its molecular models and to the nature of race non-specific resistance as well as the population dynamics of plants and the evolution of their basic resistance.

Mechanisms and Deployment of Resistance in Trees to Insects is a worldwide synthesis of tree resistance to insects. The contributions are by senior scientists and represent all the major forested regions of the world. The book constitutes a comprehensive treatment of the state of our knowledge on patterns of resistance by insect guilds and how this knowledge can be deployed to achieve the management of damaging forest insects. This book will serve as an essential reference book for all researchers and practitioners attempting to manage forest pests using genetic resistance.

In the summer of 1997 some twelve lecturers and sixty students met for ten days in Budapest Hungary in a NATO Advanced Studies Institute (ASI) to consider "New Scientific and Technical Aspects of Verification of the Biological and Toxin Weapons Convention." In many ways the meeting was ahead of its time. The Ad Hoc Group was only then about to move to the discussion of a rolling text of the Protocol to the Biological and Toxin Weapons Convention (BTWC). It had been mandated to negotiate the Protocol by the Special Conference which had considered the work of the VEREX process that had taken place following the 1991 Third Review Conference of the Convention. Now, in late 1999, after much further negotiation of the text of the Protocol we are moving towards the endgame of the negotiations. Nevertheless, the scientific and technical issues discussed in the ASI in Hungary continue to be of direct relevance to the verification of the Convention and will continue to be relevant as the eventual Protocol moves from agreement through a Preparatory Commission stage and into full implementation over the next several years. The papers in this volume are much as they were presented in Budapest both in order of presentation and in content. They were designed by the ASI co-directors, Professor Graham Pearson and Ambassador Tibor Toth (Chairman of the Ad Hoc Group) to provide an integrated overview and in-depth analysis of the issues at stake.

Emphasis in this second volume of Advances in Downy Mildew Research is on the biology of compatible interactions, forecasting and epidemiology, host specialisation, genetic variability amongst pathogen populations, novel methods for detection and systematics, and induced resistance. Two chapters focus on the related oomycete Albugo candida, which shares many pathogenic characteristics with the downy mildews and provides a valuable comparative pathosystem. Contributions on specific downy mildews include Bremia lactucae, Peronospora destructor, Peronospora sparsa, Peronospora viciae, Plasmopara halstedii, Plasmopara viticola, Pseudoperonospora cubensis and Sclerospora graminicola. Review chapters on compatibility, forecasting and systematics consider a broader range of downy mildew fungi, and compare them with other oomycete and biotrophic pathogens. The book is relevant to anyone with an interest in these unique biotrophic pathogens, either in their own right as causes of damaging diseases or as model systems for research on host-pathogen interactions. It should be read by: students, teachers and researchers in academic and research institutes; research and development personnel in the agrochemical industries; agricultural and horticultural advisers, and other extension workers.