Effects of melatonin on blueberry fruit quality and cell wall metabolism during low temperature storage

Melatonin is known to influence various physiological processes, including plant ripening; however, the effect of melatonin on postharvest blueberry fruit softening unknown. Herein, effects at different concentrations (100, 300, and 500 μmol L-1) quality parameters, cell wall substances, cell-wall-degrading enzymes, ultrastructure fruits were investigated during low-temperature storage. treatment was found effectively delay decline in firmness, slow loss soluble solids titratable acids, decrease respiration rate decay fruits. The treated with 300 L-1 exhibited best quality. promoted anthocyanin accumulation, delayed ascorbic acid degradation, maintained a low relative membrane permeability pulp, inhibited increases lipoxygenase (LOX) activity, reduced lipid peroxidation. Moreover, controlled formation pectin by inhibiting activities methylesterase (PME), polygalacturonase (PG), cellulase (Cx), β-glucosidase (β-Glu) while maintaining high contents protopectin cellulose. These results indicate that can improve antioxidant capacity as well degradation substances.