Effect Of Exogenous Substance Treatment On Fruit Quality Formation And Postharvest Storage Of Thin-Skinned Melon

Thin-skinned melon（Cucumis melo L.var.makuwa Makino）belongs to the genus Cucurbitaceae,with sweet fruits and rich flavor.However,due to geographical constraints,the fruit quality varies greatly,and the thin-skinned melon is not resistant to storage and transportation,which greatly affects its market economy.In this paper,we investigated the effects of applying different concentrations of 2,4-epi-oleicinolide（EBR）and melatonin（MT）at different stages of fruit development on fruit morphology and quality;we also investigated the effects of 1-methylcyclopropene（1-MCP）and different concentrations of MT treatments on physiological characteristics,appearance,nutritional quality and sensory quality of melon fruits stored at 10℃ and 25℃,respectively.The effects of 1-methylcyclopropene（MCP）and different concentrations of MT on physiological characteristics,appearance quality,nutritional quality and sensory quality of melon fruits stored at 10℃ and 25℃ were also studied.The results of the study were as follows:1.EBR and MT were applied once or twice at different concentrations at 10 d and20 d after pollination during the fruit development period of thin-skinned melon,and the clear water treatment was used as a control to compare the fruit development and the difference in quality between treatments at harvest.The results showed that one application of 0.1 mg·L^-1EBR or 200μmol·L^-1MT at 20 d after pollination promoted fruit development,two applications of 0.1 mg·L^-1EBR at 20 d after pollination or one application of 200μmol·L^-1MT at 10 d after pollination effectively improved fruit appearance and quality,and two applications of 0.1 mg·L^-1EBR or 200μmol·L^-1MT at20 d after pollination effectively improved fruit quality.mg·L^-1EBR twice at 20 d after pollination or 200μmol·L^-1MT twice at 10 d after pollination improved the intrinsic quality of the fruit.2.The changes of physiological characteristics,appearance quality,nutritional quality and sensory quality of thin-skinned melons stored at low temperature（10℃）and room temperature（25℃）after harvesting with 1-MCP treatment were investigated.The results showed that 1-MCP+low temperature treatment significantly reduced the respiration rate and delayed the peak of ethylene release,increased the activities of superoxide dismutase（SOD）and catalase（CAT）,and effectively inhibited the decline of fruit quality during storage.3.The changes in physiological characteristics,appearance quality,nutritional quality and sensory quality of thin-skinned melons stored at low temperature（10℃）and room temperature（25℃）after harvesting with different MT treatments were investigated.The results showed that several combinations of treatments did not show significant inhibition in respiration rate and ethylene release,and the appearance and nutritional quality of fruits were slightly reduced,but the SOD and CAT activities and sensory quality were somewhat improved.The results of this study can provide a theoretical basis for the regulation of melon fruit quality and prolonged storage period.