Integrated metabolomic and transcriptomic analysis to explore the mechanisms of ginkgo biloba leaf extract in controlling postharvest Penicillium expansum in sweet cherry

Sweet cherries (Prunus avium L.) are highly susceptible to postharvest decay caused by Penicillium expansum, leading to economic losses and health risks. The efficacy of Ginkgo biloba leaf extract (GBE) in enhancing resistance against P. expansum and preserving fruit quality was investigated. GBE significantly reduced infection rates (27.78 %) compared to the control (100 %) and maintained fruit quality by mitigating weight loss (5.84 %), preserving firmness, and stabilizing soluble solids and acids. GBE also alleviated oxidative stress by enhancing antioxidant enzyme activities (PPO, POD) and suppressing lipid peroxidation markers (MDA, LOX). Metabolomics and transcriptomics analyses revealed that the differentially expressed metabolites were primarily enriched in flavonoids (quercetin, kaempferol) and phenylpropanoid compounds (coumarins), while the differentially expressed genes were primarily enriched in pathways related to secondary metabolism, plant-pathogen interactions, and hormone signaling. Key pathways include phenylpropanoid biosynthesis and JA/SA-mediated defense responses, mediated by up-regulated genes (PavPAL, PavCHS, PavLOX2S, PavMYC2) and related transcription factors (PavMYB, PavWRKY, PavNAC). GBE inhibited genes associated with cell wall degradation (PavPG, Pavβ-GAL), while activated PR protein and hormone interaction networks. The study provides a sustainable alternative to synthetic fungicides, offering insights into natural extract-based strategies for postharvest disease management in perishable fruits.