Induced resistance in peach fruit as treated by Pichia guilliermondii and their possible mechanism

Abstract

This research aims to assess the effect of Pichia guilliermondii treatment on the improved disease resistance of the peach fruit and to explore the biocontrol mechanisms. Infection rate and lesion diameter of the yeast-treated fruit were substantially inhibited after Rhizopus stolonifer and Penicillium expansum infection, respectively. A significant increase in endogenous salicylic acid (SA) content was stimulated in peach fruit treated with P. guilliermondii. The activities of defense-related enzymes and the SA synthase in peaches were also improved after P. guilliermondii treatment, and the expression of pathogenesis-related genes was activated. Thus, P. guilliermondii may be a biological elicitor-activated systemic acquired resistance by the SA signaling pathway. The new understanding regarding the mechanism of antagonist yeast could could be conducive for controlling fruit postharvest diseases in the future.