VlWRKY71 mediates MeJA-induced terpene biosynthesis for aroma enhancement during grape berry ripening

Methyl jasmonate (MeJA) regulates climacteric fruit ripening, but its non-climacteric grape mechanisms are unclear. We treated ‘Zhuosexiang’ ( V. vinifera L. × V. labruscana Bailey) grapes with MeJA at pre-veraison, tracking physiology, hormones, metabolites and transcripts. The results show that treated berries ripened faster, as shown by earlier color break and higher sugar content. MeJA triggered a transient spike in jasmonic acid-isoleucine (JA-Ile) at veraison, followed by a decline, while abscisic acid (ABA) increased gradually and remained at high levels. Weighted gene co-expression network analysis (WGCNA) identified a hub gene, VlWRKY71, which binds W-box motifs in the promoter of VlDXS1. VlWRKY71 expression correlated with JA-biosynthetic VlLOX1 / VlOPR3 , suggesting a JA feedback loop. Overall, VlWRKY71 links MeJA perception to terpene production and ripening. • MeJA treatment accelerated grape berry ripening and increased the content of aroma components. • VlWRKY71 was identified by WGCNA as a key hub regulator of MeJA responses, which can activate the VlDXS1 promoter to drive terpene synthesis.