Jasmonic Acid Signaling in Environmental Stress Adaptation of Horticulture Crops

Abstract

 Jasmonic acid (JA) and its derivative methyl jasmonate (MeJA) are central lipid-derived signaling molecules that regulate plant growth and stress acclimation. Under abiotic stresses commonly encountered in horticultural production, such as salinity, drought, temperature extremes and heavy metal toxicity. JA accumulation via the octadecanoid pathway and conversion to the bioactive conjugate jasmonoyl-isoleucine (JA-Ile) activate the SCFCOI1–JAZ core signaling module. The activation releases transcription factors to coordinate downstream defense and acclimation responses. At the physiological level, exogenous application of JA or MeJA frequently enhances stress tolerance by strengthening antioxidant and glyoxalase systems; promoting osmotic adjustment through the accumulation of proline, soluble sugars and other compatible solutes; maintaining ion homeostasis, modulating stomatal behavior and water-use efficiency, stabilizing cellular membranes and the photosynthetic apparatus; and enhancing detoxification and sequestration processes during metal stress. Moreover, JA extensively interacts with other phytohormones, including abscisic acid (ABA), salicylic acid (SA), ethylene, and brassinosteroids, forming context-dependent hormonal networks that balance growth and defense, ultimately influencing crop yield and quality. In this review, we integrate recent evidence on JA-regulated mechanisms in horticultural crops and propose a conceptual framework that links JA signaling modules to core physiological responses across diverse stress conditions. We also identify key knowledge gaps, including the optimization of dose and timing under field and combined-stress scenarios, cultivar-specific sensitivity to JA, and the need to integrate omics-level markers with agronomic performance. Addressing these challenges will facilitate the rational application of jasmonates to enhance climate resilience in horticultural crops.