Abscisic acid activates pathogenesis-related defense gene signalling in Lentils

Abstract

Plant hormones are pivotal in signaling the activation of disease defense mechanisms in many important plant pathosystems. This chapter outlines the proposed involvement and mechanism of hormones in defense mechanisms that are triggered in response to common crop related pathogens. The expression of two previously characterized pathogenesis-related (PR) protein genes from lentil, known to be involved in defense to the nectrotrophic fungal pathogen Ascochyta lentis, were assessed. For this, expressions of lentil PR4 and PR10 genes in leaf and stem tissues of the highly resistant lentil accession ILL7537 were assessed following treatment with various hormonal compounds. Similar to that previously detected following treatment with the pathogen, ABA significantly upregulated the expression of both genes at all the time points assessed. Whilst ACC, JA, and SA produced a null or downregulation response. We therefore postulate that ABA is a key hormonal activator of the signal transduction of necrotrophic fungal defense responses in lentil.