Role of Methyl thiobutyrate to Botrytis cinerea on cucumber

This study shows that a 2 mg/mL solution of MTB inhibits <i>B. cinerea</i> growth by 98.6% in vitro. In vivo, MTB effectively reduces <i>B. cinerea</i> infection in cucumbers, alleviates necrotic damage in leaf tissues, and significantly reduces disease severity. Transcriptomic analysis reveals that MTB activates the plant immune responses by modulating key MAPK cascade signaling genes and upregulating basal defense genes, including chitinase, pectinase, and lignin biosynthesis genes. Furthermore, MTB influences the signaling pathways of salicylic acid (SA), jasmonic acid (JA), and ethylene (ET), resulting in the upregulation of genes such as peroxidase (POD), phenylalanine ammonia-lyase (PAL), lipoxygenase (LOX), and ethyleneresponsive transcription factors (ERFs). These results demonstrate the potential of MTB as an effective biocontrol agent against <i>B. cinerea</i> and provide valuable insights into its underlying mechanisms of action.