Transcriptomic analysis of the mechanisms involved in enhanced antagonistic efficacy of Meyerozyma guilliermondii by methyl jasmonate and disease resistance of postharvest apples

Abstract

The biological control ability of the yeast, Meyerozyma guilliermondii, in restaining Penicillium expansum infection in apples, has been reported to be enhanced by methy jasmonate (MeJA). Our previous research unveiled the possible physiological biocontrol mechanisms of the yeast; however, the related molecular mechanisms were unclear. This study aimed to investigate the possible molecular mechanisms behind the enhanced biological control efficacy of M. guilliermondii cultured with MeJA through transcriptomic approaches. The transcriptome analysis of MeJA cultured M. guilliermondii indicated that MeJA induced changes in oxidative stress response, energy metabolism, cell wall synthesis and stability and cell growth. Meanwhile, transcriptomic analysis of apples treated with M. guilliermondii and MeJA cultured M. guilliermondii was also investigated. Our results witnessed that MeJA cultured M. guilliermondii enhanced the cell wall synthesis, antioxidant activity, plant disease resistance, increased peroxisome proliferation, energy metabolism, phenylpropane metabolism and other pathways of apples. Expression levels of PPO, EXPA1, TFT6, GHR5, CYP73 and other genes were increased, which enhanced the apple's stability, antioxidant, stress resistance and energy metabolism. This study will provide a theoretical basis for improving the biocontrol efficacy of antagonistic yeast cultured with MeJA.