2-Phenylethanol biocontrol postharvest tomato gray mold and its effect on tomato quality

Abstract

Botrytis cinerea is a highly destructive fungal pathogen responsible for substantial economic losses in fruit and vegetable production. Volatile organic compounds (VOCs) emitted by plants or microorganisms show promise as sources for novel biocontrol strategies. This study evaluated the effect of 2-phenylethanol (2-PE) on the quality of tomatoes and its antifungal efficacy against B. cinerea, alongside exploring possible mechanisms of action. The results showed that 2-PE notably increased the soluble sugar content in postharvest tomatoes without adversely affecting other quality parameters. Moreover, 2-PE markedly suppressed the growth of B. cinerea mycelium and reduced the incidence of infection in tomatoes in a dose-dependent manner. It also increased the activity of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT), phenylalanine ammonia-lyase (PAL), β-1,3-glucanase (GLU), chitinase (CHI), and their corresponding gene expression, enhancing the host defense capability of tomatoes. Treatment with 2-PE led to the downregulation of genes linked with the pathogenicity of the fungus. Concurrently, 2-PE triggered the expression of autophagy-related genes and provoked the accumulation of reactive oxygen species (ROS) in B. cinerea. The resulting ROS-induced oxidative stress compromised membrane integrity, which facilitated the leakage of cellular components and culminated in the death of B. cinerea cells. Collectively, these outcomes suggest significant potential for 2-PE in the development of a novel biocontrol agent.