Early defence responses induced by two distinct elicitors derived from a Botrytis cinerea in grapevine leaves and cell suspensions

Abstract

Two elicitors, termed herein as the botrycin and the cinerein, have been isolated from the crude mycelial cell wall and from culture filtrate preparations, respectively, of a fungal necrotrophic pathogen Botrytis cinerea (Pers. et Fries). In grapevine (Vitis vinifera L. cv. Limberger) both elicitors caused the formation of necrotic lesions that mimic a typical hypersensitive response and apoptosis-related events including protoplast condensation and DNA laddering. Infiltration of minute amounts of the respective elicitors into leaves stimulated a rapid transcriptional activation of genes encoding enzymes of the phenylpropanoid pathway. Cultured grapevine cells respond differentially to respective elicitors. Significant differences were demonstrated in the ability of botrycin and cinerein to induce ion fluxes across the plasma membrane and the production of reactive oxygen species. As demonstrated by immunokinase assays, both botrycin and cinerein activated specific and distinct MAP kinases indicating that grapevine cells that perceived elicitors generated a cascade of signals acting at local, short, and long distances. Using a highly parallel antibody microarray profiling approach, the timing, dynamics, and regulation of the expression of 97 specific genes in elicitor-treated cells of grapevine was analysed.