Exogenous methyl jasmonate alleviates chilling injury in postharvest green-peel ripening mango cv. ‘Guire 82’ by boosting the antioxidative system and affecting energy metabolism

Mangoes are chilling-sensitive fruits and prone to suffering chilling injury (CI) when stored below 13 °C, compromising their economic value. Methyl jasmonate (MeJA) is an essential phytohormone that affects the development and postharvest quality of mangoes. However, the effects and mechanisms of MeJA on CI in stored mangoes are inadequately understood, especially in green-peel ripening mango varieties. This study investigated how MeJA treatment impacted the green mango cv. ‘Guire 82’ during 4 °C storage. The results show that MeJA significantly reduced CI and delayed firmness loss. MeJA also improved the antioxidant activities (superoxide dismutase, peroxidase, and catalase) and up-regulated their gene expression. MeJA inhibited 12-oxophytodienoate reductase (key enzyme of JA biosynthesis) activity. Although adenosine triphosphate, adenosine diphosphate, and adenosine monophosphate levels declined in MeJA-treated fruits, a transient increase in energy charge during early storage. The above results support the use of exogenous MeJA to alleviate CI in postharvest mango, indicating its role in bolstering antioxidant defense system, maintaining membrane integrity, and affecting energy metabolism. Our findings enrich the postharvest biology regarding the application of MeJA for improving cold tolerance in green-peel ripening mangoes.