This book is a first attempt to link well-known plant resistance phenomena with emerging concepts in molecular biology. Resistance phenomena such as the local lesion response, induced resistance, "green islands" and resistance in various crop plants are linked with new information on gene-silencing mechanisms, gene silencing suppressors, movement proteins and plasmodesmatal gating, downstream signalling components, and more.

Concern about the environmental consequences of the widespread use of pesticides has increased, and evidence of pesticide-resistant virus vectors have continued to emerge. This volume presents a timely survey of the mechanisms of plant resistance and examines current developments in breeding for resistance, with particular emphasis on advances in genetic engineering which allow for the incorporation of viral genetic material into plants. Discusses the mechanisms of innate resistance in strains of tobacco, tomato, and cowpea; various aspects of induced resistance, including the characterization and roles of the pathogenesis-related proteins; antiviral substances and their comparison with interferon; and cross-protection between plant virus strains. Also presents several papers which evaluate the status of genetic engineering as it relates to breeding resistant plants. Among these are discussions of the potential use of plant viruses as gene vectors, gene coding for viral coat protein, satellite RNA, and antisense RNA, and practical issues such as the durability of resistant crop plants in the field.

Plant viruses cause many of the most important diseases threatening crops worldwide. Over the last quarter of a century, an increasing number of plant viruses have emerged in various parts of the world, especially in the tropics and subtropics. As is generally observed for plant viruses, most of the emerging viruses are transmitted horizontally by biological vectors, mainly insects. Reverse genetics using infectious clones--available for many plant viruses--has been used for identification of viral determinants involved in virus-host and virus-vector interactions. Although many studies have identified a number of factors involved in disease development and transmission, the precise mechanisms are unknown for most of the virus-plant-vector combinations. In most cases, the diverse outcomes resulting from virus-virus interactions are poorly understood. Although significant advances have been made towards understand the mechanisms involved in plant resistance to viruses, we are far from being able to apply this knowledge to protect cultivated plants from the all viral threats.The aim of this Special Issue was to provide a platform for researchers interested in plant virology to share their recent results. To achieve this, we invited the plant virology community to submit research articles, short communications and reviews related to the various aspects of plant virology: ecology, virus-plant host interactions, virus-vector interactions, virus-virus interactions, and control strategies. This issue contains some of the best current research in plant virology.

Plant resistance to pathogens is one of the most important strategies of disease control. Knowledge of resistance mechanisms, and of how to exploit them, has made a significant contribution to agricultural productivity. However, the continuous evolution of new variants of pathogen, ana additional control problems posed by new crops and agricultural methods, creates a need for a corresponding increase in our understanding of resistance and ability to utilize it. The study of resistance mechanisms also has attractions from a purely academic point of view. First there is the breadth of the problem, which can be approached at the genetical, molecular, cellular, whole plant or population lev~ls. Often there is the possibility of productive exchange of ideas between different disciplines. Then there is the fact that despite recent advances, many of the mechanisms involved have still to be fully elucidated. Finally, and compared with workers in other areas of biology, the student of resistance is twice blessed in having as his subject the interaction of two or more organisms, with the intriguing problems of recognition, specificity and co-evolution which this raises.

The Encyclopedia of Plant Viruses and Viroids provides an up-to-date information on the viruses and viroids infecting all types of cultivated and weed plants at global level; and is unique among plant virology texts as it is organized alphabetically by the genus name of the host plant infected. It allows the reader to readily determine all of the different viruses currently reported naturally infecting the plant genus and species. Information is provided for each virus and viroids on common synonyms, current taxonomic status, geographical distribution, symptoms induced, other known hosts, means of transmission and properties of both the virus particles and the genome. Where ever the same virus is known to infect multiple hosts, host-specific information, biological properties and genome characters are presented under each host affected. The index can be utilized to identify other crops infected by the same virus, showing which other crops might be at risk of infection in the event of introduction of a virus that has not previously reported in an area, or which might serve as potential virus reservoirs for infection of more sensitive or economically important crops than the host in which it is initially identified. The taxonomy and nomenclature of the viruses and viroids are followed based on the current guidelines of the 10th ICTV Report, covering up to 2018 and also about many new viruses and viroids that have been reported but not yet recognized as species by ICTV, have been included in this Encyclopedia. The uniqueness of this Encyclopedia is that all the known viruses and viroids affecting more than 1010 plant species at global level are described and the plant species are arranged in alphabetical order of the scientific name of the plant along the relevant information on 1518 viruses and viroids and is the ready-reckoner of the global plant species and their viruses and viroids for students, scientists, teachers of Plant Pathology& Virology; and also for the crop protection professionals, agricultural policymakers, seed companies and quarantine agencies.

The seminal text Plant Virology is now in its fifth edition. It has been 10 years since the publication of the fourth edition, during which there has been an explosion of conceptual and factual advances. The fifth edition of Plant Virology updates and revises many details of the previous edition while retaining the important earlier results that constitute the field's conceptual foundation. Revamped art, along with fully updated references and increased focus on molecular biology, transgenic resistance, aphid transmission, and new, cutting-edge topics, bring the volume up to date and maintain its value as an essential reference for researchers and students in the field. - Thumbnail sketches of each genera and family groups - Genome maps of all genera for which they are known - Genetic engineered resistance strategies for virus disease control - Latest understanding of virus interactions with plants, including gene silencing - Interactions between viruses and insect, fungal, and nematode vectors - Contains over 300 full-color illustrations

Viruses are a huge threat to agriculture. In the past, viruses used to be controlled using conventional methods, such as crop rotation and destruction of the infected plants, but now there are more novel ways to control them. This volume focuses on natural and engineered virus resistance, the two major strategies used for crop protection. - Contributions from leading authorities - Informs and updates on all the latest developments in the field