Breeding for biotic stress resistance/tolerance in plants

Abstract

The long-term goal of crop improvement for biotic stress tolerance in plants is a traditional objective of breeders. Plants must continuously defend themselves against attacks from bacteria, viruses, fungi, invertebrates, and even other plants. This chapter will therefore summarize the benefits and drawbacks of resistance versus chemical protection. Attempts will be made to provide a description on the effective genetic and molecular mechanisms that plants have developed to recognize and respond to infection by a number of pathogens and pests, such as non-host resistance, constitutive barriers and race-specific resistance, including recent advances in elucidating the structure and molecular mechanisms used by plants to cope with pathogens and pest attacks. This chapter also covers the most relevant problems in breeding for resistance to parasites and will include aspects related to specificity of defense mechanisms, specificity of parasitic ability, inheritance of resistance, gene-for-gene interaction, and durability of resistance. Major considerations in breeding for resistance to parasites, conventional sources of resistance and possible alternatives, namely mutation breeding, genetic manipulations, tissue cultures, and molecular interventions to develop plants resistant to pests and pathogens will also be dealt.