Multi-omics reconstruction of ozone-activated defense cascades in postharvest pears.

Postharvest decay causes substantial economic losses in pear fruit. Ozone treatment has preservation potential, but the molecular mechanisms of ozone-induced preservation have not been systematically elucidated using an integrated multi-omics analysis. This study employed integrated multi-omics analyses to investigate the molecular mechanism through which ozone suppresses postharvest decay in pear fruit by coordinating defense signaling and metabolic pathways. Ozone treatment reduced the fruit decay index by suppressing key decay-associated microbial community. Metabolomic analysis revealed that ozone induced the accumulation of three key antimicrobial compounds (isoquinoline, 4-methylphenol, and vitexin), which exhibited potent efficacy against major postharvest pathogens. Transcriptomic analysis revealed that ozone treatment activated a plant defense network, in which the MAPK signaling pathway acted as a central regulatory hub, regulating flavonoid biosynthesis and other metabolic pathways that were associated with antimicrobial compounds. These findings provide a systematic molecular insight into ozone-induced resistance, contributing to the development of targeted preservation strategies.