Viral diseases cause considerable crop losses throughout the world. Concern about the environmental consequences of widespread use of pesticides has increased and examples of pesticide-resistant virus vectors have emerged. This symposium presents a survey of the mechanisms of plant resistance and possible approaches to breeding for resistance. An overview of the genetics of resistance is provided. The mechanisms of innate resistance, in strains of tobacco, tomato and cowpea, are discussed. Various aspects of induced resistance are covered: the characterization and roles of the pathogenesis- related proteins; antiviral substances and their comparison with interferon; and cross-protection between plant virus strains. Advances in genetic engineering have led to novel approaches to breeding for resistance. Several papers evaluate the incorporation of viral genetic material (such as genes coding for viral coat protein, satellite RNA and antisense RNA) as a means of conferring resistance. The possibility of using plant viruses as gene vectors is explored. The discussion after each paper serves to highlight progress made and areas which remain to be investigated. Practical issues, such as the durability of resistance in the field, are raised.
Table of Contents
PARTIAL TABLE OF CONTENTS: Partial table of
Resistance of Cowpeas to Cowpea Mosaic Virus
and to Tobacco Ringspot Virus (G. Bruening,
Resistance Mechanisms of Tobacco Mosaic Virus
Strains in Tomato and Tobacco (M. Nishiguchi
& F. Motoyoshi).
The Role of Pathogenesis-related proteins (J.
Antoniw & R. White).
Mechanism of the Hypersensitivity Reaction of
Plants (B. Fritig, et al.).
Analysis of the N Gene of Nicotiana (D.
Dunigan, et al.).
Mechanisms of Cross-protection between Plant
Virus Strains (J. Sherwood).
Genetic Engineering of Plants for Protection
against Virus Diseases (R. Beachy, et al.).
Resistance to Viral Disease through
Expression of Viral Genetic Material from the
Plant Genome (D. Baulcombe, et al.).
Plant DNA Viruses as Gene Vectors (B. Hohn,
Pathogenesis (R. Fraser).
Genetic Engineering Approaches to Plant
Resistance (L. van Vloten-Doting).