Cacao Diseases

This book reviews the current state of knowledge concerning cacao pathogens and methods for their management. Topics discussed include the history, biology and genetic diversity of Moniliophthora species (which cause witches’ broom and frosty pod rot) and Phytophthora species (which cause black pod rot) that cause diseases resulting in major losses to cacao production. Emerging pathogens such as Cacao swollen shoot virus and Ceratobasidium theobromae (which causes vascular streak dieback) are also discussed in detail, along with many pathogens of significant local concern. Most of these pathogens represent major risks to global cacao production should they expand into new areas, breaking out of their current limited distributions. By considering cacao diseases as a group, similarities in the available tools and techniques used in their management become apparent, as do their limitations. Gaps in our current knowledge of cacao pathogens and the management of the diseases they cause are detailed, and suggestions for future research directions are provided. This insight allows readers to consider cacao disease threats from a more comprehensive, global perspective and paves the way for an improved synergy of efforts between the various research programs, agencies, and industries, both private and public, with vested interests in cacao production, and cacao farmers.

The Monograph deals with the conception, planning, implementation, results and conclusions of the International Witches' Broom Project (IWBP), which was set up in 1985 with the aim of producing an economic management system for witches' broom disease of cocoa. The contributions of the various sponsors, and the roles played by the participating organizations and scientists are described in the introductory chapter. Chapter 2 provides a review of what was, and what was not known from published literature about the cocoa witches' broom pathosystem in 1989. The scope of the project and the approaches used are covered in Chapter 3, while Chapters 4 to 13 report on the field studies themselves in detail. The recent appearance of witches' broom in the important cocoa area of Bahia in Brazil is described in Chapter 14, before disease management recommendations are summarised and future prospects considered in the closing chapters. The many man-years of field research in the IWBP in a total of six countries generated much useful information which was analyzed both in the individual countries and collectively. Even with a document of this size, certain information and analyses with less direct relevance to disease management had to be omitted. It is expected that more detailed treatments of certain aspects will emerge in scientific papers, and further analyses will be undertaken.

This book reviews the current state of knowledge concerning cacao pathogens and methods for their management. Topics discussed include the history, biology and genetic diversity of Moniliophthora (which causes witches' broom and frosty pod rot) and Phytophthora species (which causes black pod rot) that cause diseases resulting in major losses to cacao production. Emerging pathogens such as Cacao swollen shoot virus and Ceratobasidium theobromae (which causes vascular streak dieback) are also discussed in detail, along with many pathogens of significant local concern. Most of these pathogens represent major risks to global cacao production should they expand into new areas, breaking out of their current limited distributions. By considering cacao diseases as a group, similarities in the available tools and techniques used in their management become apparent, as do their limitations. Gaps in our current knowledge of cacao pathogens and the management of the diseases they cause are detailed, and suggestions for future research directions are provided. This insight allows readers to consider cacao disease threats from a more comprehensive, global perspective and paves the way for an improved synergy of efforts between the various research programs, agencies, and industries, both private and public, with vested interests in cacao production, and cacao farmers.

Plant pathogens, the causal agent of infectious plant diseases, influence our lives more than just as an economic impact through yield lost. The study of plant pathogens has given rise to the development of new sciences, new technologies for plant breeding, and the agrochemical industry for pesticide developments. Yet, all our actions and efforts to suppress or eradicate them constantly pressures these various organisms to evolve and adapt for survival. Therefore today, when facing climate changes, accelerated transport of plants and plant products, and world population growth, we have to ask quo vadis phytopathology. Like Alice in Wonderland “If we wish to go anywhere we must run twice as fast as that” so we need to constantly broaden our knowledge. However, today’s literature abounds with knowledge about plant pathogens. Hence, this book intends to present to the reader all the latest material and knowledge about plant pathogens, changes or refinements in plant disease epidemiology, and new approaches and materials used for plant pathogen control. Hopefully, this book will be of interest to those working within the field and looking for an up-to-date introduction. We hope it also interests students and thereby, will influence the future development of phytopathology and our better coexistence with plant pathogens.

Forest Microbiology: Tree Diseases and Pests, Volume Three in the Forest Microbiology series, provides an overview of major disease agents of trees, including viruses, phytoplasma, bacteria, fungi, nematodes and major insect pests. With a strong emphasis on genetics, biochemistry, physiology, evolutionary biology and population dynamics of the organisms involved, this book provides a comprehensive understanding on the health of forests. Sections cover important pest threats such as bark beetles, emerald ash borer, coffee borers, leaf cutting ants, cocoa mirids, and more. This volume highlights a range of emerging diseases of forest trees in temperate and tropic regions as well as information on habitats. Forest trees play crucial roles not only for mitigating effects of the climate change but also for their considerable economic and ecological value. Forest trees are equally vital as an alternative bioenergy source and play important roles in pollution abatement and the maintenance of biodiversity. Timber and its associated products from forest trees contribute substantially to the revenue generation of many countries of the world. Includes case studies of complex diseases of economically important trees Highlights novel approaches to managing tree pests and diseases in a changing climate Focuses on the many functions of microbial disease agents of trees Addresses major insect pests of boreal, temperate and tropical trees