Résumé
The best strategy to extend the shelf life of fresh horticultural produce is to keep it at a low temperature. However, storing fruits and vegetables at a temperature lower than their recommended storage temperature and above the freezing point for a prolonged time leads to the development of chilling injury (CI). Melatonin (MT) being a versatile biological signal has been reported to possess antioxidant properties that aid in mediating stress response and extending the postharvest storage life of horticultural crops. Among CI-induced mechanisms, MT substantially reduces oxidative stress by elevating the reactive oxygen species scavenging and triggering the phenol accumulation in association with 2, 2-diphenyl-1 picryl hydrazyl scavenging activity. Besides, MT increases intracellular energy by maintaining a proper ratio of unsaturated to saturated fatty acid and improving cellular fluidity. Additionally, MT regulates arginine metabolism by maintaining the gamma-aminobutyric acid synthesis. Furthermore, MT encodes the mitogen-activated protein kinases, and calcium-dependent protein kinases cascade and acclimate to cold stress by activating C-repeat binding factors and helps in maintaining postharvest quality. This review reports the recent progress of MT-induced physiological, biochemical, and molecular mechanisms for enhancing chilling tolerance, which can elevate the marketability and earnings from postharvest horticultural crops.
Chilling injury during storage is a common problem in fruits and vegetables.Melatonin plays a vital role in mitigating postharvest chilling injury.Melatonin increases intracellular energy by maintaining a proper ratio of unsaturated to saturated fatty acid.Melatonin imparts chilling tolerance via reactive oxygen species, arginine pathway, GABA, and proline accumulation.