EFFECTS OF 1-METHYLCYCLOPROPENE ON STORAGE QUALITY AND ANTIOXIDANT ACTIVITY OF HARVESTED “YUJINXIANG” MELON (CUCUMIS MELO L.) FRUIT

Harvested “Yujinxiang” melon (Cucumis melo L.) fruits were treated with 0, 0.25, 0.5 or 1.0 µL/L 1-methylcycopropene (1-MCP) for 24 h at 20 ± 1C and then stored at 10 ± 1C, 70–80% RH. Results showed that 1.0 µL/L 1-MCP was the most effective treatment in delaying decline of the melon firmness during storage for 20 days. Decay development and ethylene production of the fruit were suppressed by 1-MCP during storage for 24 days. Fructose and glucose contents and the sweetness index increased in the 1-MCP-treated melon. The 1-MCP treatment increased activities of superoxide dismutase, ascorbate peroxidase and glutathione reductase; stimulated a rapid accumulation of glutathione; and lowered hydrogen peroxide level in the melon. These beneficial effects of 1-MCP on delaying ripening and softening of the melon may be because of its action on inhibiting ethylene as well as increasing antioxidant potential during storage. PRACTICAL APPLICATIONS The cantaloupe melons are very easy to ripen and soften and are susceptible to pathogenic infections after harvest. 1-Methylcyclopropene (1-MCP), the competitive ethylene inhibitor, could delay the progress of ripening and softening of the “Yujinxiang” melon fruit, and 1.0 µL/L 1-MCP was proved to be optimal for the application. The 1-MCP treatment could decrease decay but improve the edible quality of the melon during storage. The 1-MCP gas is easily released by dissolving the commercial SmartFresh™ powder into water and can be rapidly diffused into the melon tissue without any complicated facilities. Thus, the application of 1-MCP fumigation would provide a practical approach for reducing postharvest losses, maintaining the edible quality and extending the postharvest life of the cantaloupe melon during storage, handling, transportation and processing. In addition, this method would offer an alternative to conventional protection of melons using artificial synthetic fungicides.