Study On 1-Methylcyclopropene Delay Postharvest Senescence Of Hami Melon Fruit

hami melon (Cucumis melo L)'Zaohuangmi'were used to study the effect of 1-MCP on postharvest physiology and qualities. Melon fruit were treated with 0.1μl·L^-1,1μl·L^-1,5μl·L^-1 1-MCP at room temperature for 24 hours on the day of harvest ,then stored at 25℃.Treatment with 1μl·L^-1 and 5μl·L^-1 1-MCP inhibited significantly respiration rate and ethylene production, delayed or suppressed the occurrence of climacteric peaks of respiration rate and ethylene during storage. The both of increasing in electrolyte leakage of mesocarp tissure and lossing of firmness of fruit were suppressed, softening of fruit flesh was slowed effectively by 1-MCP treatment. No difference at TA content of fruit among treatments were observed throughout storage. 1-MCP treated with 1μl·L^-1,5μl·L^-1 fruit maintained SSC, reduced chlorophyll degradation of fruit epicarp at 12d respetively after harvest. The postharvest fruit disease was inhibited dramatically , decay rate and index of melon fruit were reduced by all 1-MCP treatments in comparison to the control. 1-MCP-treated fruits delayed the onset of fruit disease by 6d,10d and 12d respectively compared to controls. The same time, the other variety 'Golden queen' were used this experiment. The results showed that treatment with 1-MCP before storage significantly inhibited respiration rate and ethylene production, The both of increasing in electrolyte leakage of mesocarp tissue and lossing of firmness of fruit were suppressed, softening of fruit flesh was slowed effectively by 1-MCP treatment. The postharvest fruit disease was dramatically inhibited, decay rate were reduced by 1-MCP treatments in comparison to the control.hami melon ( Cucumis melo L)'Zaohuangmifruit'treated with 1μl·L^-1 1-MCP were used to study the mechanism of 1-MCP in delaying postharvest senescence of early hami melon fruit. The results showed that treatment with 1-MCP inhibited the decline of CAT activity, increased SOD activity at the beginning of storage, accelerated the rising of POD activity and reached it peak at 4th day, depressed the production rate of superoxide anion, and declined the MDA content of melon fruit. Fruit treated with 1-MCP maintained fine firmness due to 1-MCP inhibited the enzymes activity of PG,PME,GAL,β-glucosidase in melon fruit. Further study showed that 1-MCP increased ACC accumulation, inhibited ACO activity, delayed the increasing of ACS activity at the late stage of storage.