Chapter 28 - Phytoalexin biosynthesis through RNA interference for disease resistance in plants

Abstract

World food production needs to rise by 70% to feed growing population. Among various strategies, reducing losses caused by biotic stresses could help to meet raising food production. Phytoalexins plays an important role by providing appropriate defense response on onset of infection by a pathogen. Till date, several phytoalexins have been reported in different crops. Among various molecular tools, RNA interference (RNAi) has emerged as a potential technology for silencing of particular genes. It functions by slicing messenger RNA before it is translated into a protein. RNAi has several applications in agriculture including understanding the role of a particular gene, silencing of a targeted gene for management of pest and diseases, upregulation of a particular trait by suppressing the inhibitors, etc. Several genes were reported to hinder the phytoalexin synthesis. Silencing of those genes using RNAi increases the accumulation of phytoalexins which provided additional defense against invading pathogen. Some pest/pathogen reported to produce substances which degrade the phytoalexin and turned the resistant plant into susceptible. RNAi silencing of these chemical substances in pest/pathogen help plant to retain the effect of phytoalexins. In addition to this, RNAi can also be used to elucidate the function of the gene(s) responsible for phytoalexin production. In this chapter, we summarized details of phytoalexins and the role of RNAi in phytoalexins synthesis.