Cuticular wax removal on reactive oxygen species-related mechanisms and on the quality of Hami melon cultivars

Epicuticular wax is the outermost protective layer of fruit against abiotic stress. It is easily removed or destroyed during the postharvest transportation and handling of fruit. In this study, the effects of wax layer removal on the postharvest quality of Hami melon fruit and its possible mechanism were explored. The results showed that wax removal accelerated fruit softening, water loss, and decay, reduced sensory and nutritional quality, and shortened shelf life. At the end of storage, the antioxidant enzyme activity and non-enzymatic antioxidant content of wax-removed fruit were reduced, while the accumulation of reactive oxygen species and lipid peroxidation were accelerated. Moreover, the organelle membrane structure and plastids were destroyed. Therefore, epicuticular wax layer plays an important role in maintaining postharvest fruit quality. This study will improve our understanding of the biological function of Hami melon fruit epicuticular wax and helpful for developing effective preservation measures to delay fruit decay. • Epicuticular wax layer of Hami melon fruit has an irregular lamellar structure. • Wax layer loss affects the sensory and nutritional quality of Hami melon fruit. • Epicuticular wax removal disrupts reactive oxygen metabolism and membrane structure.