MeJA regulates aroma biosynthesis in kiwifruit during postharvest cold storage-to-shelf transition: An integrated volatilomics and transcriptomics analysis

Abstract

This study aimed to clarify the regulatory effect of methyl jasmonate (MeJA) on the postharvest quality of cold-stored kiwifruit during shelf life. Physiological analyses showed that MeJA treatment significantly delayed fruit softening, suppressed ethylene production and respiratory intensity without significantly affecting total soluble solids content. Regarding aroma components, MeJA notably increased the accumulation of total volatile compounds, especially esters and ketones, thereby reshaping the fruit aroma profile. RNA sequencing (RNA-seq) and weighted gene co-expression network analysis (WGCNA) identified the MEblack module, which was enriched in fatty acid metabolism and closely associated with ester accumulation. MeJA upregulated key genes involved in aroma synthesis, including FAD , LOX , ADH , and AAT . Transient overexpression assays confirmed that AcAAT17 , a key AAT gene, significantly enhanced AAT enzyme activity and ester accumulation. Collectively, MeJA improves the flavor quality of cold-stored kiwifruit by mediating transcriptional reprogramming of aroma biosynthesis pathways.