Jasmonate-Induced Metabolic Reprogramming Enhances Fruit Quality, Bioactive Compounds, and Stress Tolerance

Jasmonates (JAs), including jasmonic acid (JA), methyl jasmonate (MeJA), jasmonoyl-isoleucine (JA-Ile), and cis-jasmone, have emerged as central integrators of plant stress adaptation, developmental regulation, and fruit quality formation in horticultural crops. This review comprehensively summarizes recent advances in JA biosynthesis, metabolic conversion, signal perception, and downstream regulatory networks governing abiotic stress resilience and quality-associated traits. We highlight the coordinated chloroplast-peroxisome biosynthetic pathway leading to the formation of bioactive jasmonates and discuss the molecular basis of JA signaling mediated through the SCF^COI1-JAZ co-receptor complex and key transcriptional regulators, including MYC, MYB, NAC, ERF, WRKY, and bHLH families. Emerging evidence demonstrates that JA signaling orchestrates reactive oxygen species (ROS) homeostasis, antioxidant defense, osmotic adjustment, secondary metabolism, hormonal crosstalk, and stress-responsive gene expression in response to drought, salinity, temperature extremes, and heavy metal toxicity. Beyond stress adaptation, jasmonates play pivotal roles in regulating fruit ripening, anthocyanin biosynthesis, phenolic accumulation, aroma volatile production, cell wall remodeling, vitamin C metabolism, and postharvest quality maintenance. We also discuss recent progress in multi-omics integration, epigenetic regulation, CRISPR/Cas-based genome editing, systems biology, and precision agriculture approaches that are accelerating understanding and manipulation of JA-mediated pathways in horticultural species. This review provides a mechanistic framework linking JA signaling with metabolic plasticity, stress adaptation, and fruit quality. However, major knowledge gaps remain regarding context-dependent JA responses, hormone crosstalk, metabolic trade-offs, and field-scale validation. Future research should integrate multi-omics, spatial analyses, and standardized field trials to develop precise strategies for improving fruit quality and stress tolerance.