| Xinjiang is the largest high-quality melon（Cucumis melon L.）origin,Xinjiang melon has been deeply loved by the vast majority of consumers as its good taste,rich aroma,fleshy and juicy,sold well all over the country and exported to many countries.‘Boxiekexin’melon is typical climacteric fruits,Compared with other melon,‘Boxiekexin’melon is the loss of all commodity value storage at normal temperature for 3～5 d,Its prominent feature is rapid softening and liquefaction after harvest.In storage,an effective storage method has not been established to delay its senescence,mature and senescence,and improve its commodity value after harvest.Since the‘Boxiekexin’melon is particularly sensitive to ethylene and1-MCP regulating its postharvest senescence.It was treated which using 500 mg/L ethylene spraying and 2μL/L 1-MCP fumigate for 24 hours.By studing the effects of ethylene and 1-MCP treatment on quality and physiological metabolism of‘Boxiekexin’melon,revealing the mechanism of Postharvest Senescence of melon fruit,It provided a the oretical basis for the postharvest storage and preservation of‘Boxiekexin’melon.The main research is as follows:（1）Research the effects of ethylene and 1-MCP treatment on quality and physiological metabolism of‘Boxiekexin’Melon.The results show that 1-MCP could inhibit the respiratory intensity and enlargement of cell membrane permeability in melon,keep of fruit firmness of melon,inhibit the content of soluble solids,reduce sugar content,total sugar content,titratable acid content and Vc content decreased.Ethylene treatment can promote the respiration of the fruit,promote the reduction of fruit firmness and soluble solids,enlargement of cell membrane permeability,In storage 4～9 d,ethylene treatment promoted the decrease of titratable acid content in melon fruit.（2）Research the effects of ethylene and 1-MCP treatment on postharvest reactive oxygen metabolism of‘Boxiekexin’melon.The results showed that the O2?-production rate in the melon fruit of the ethylene treatment group was higher than the control group in storage 3～9 d,MDA content was higher than the control group in storage 0～9 d,the activity of active oxygen metabolism related enzymes in the ethylene treatment group were lower than the control group,the activity of CAT,POD,APX reached the peak at fourth day,It was 17.42%,29.61%and 3.25%lower than the control group.The O2?--production rate and MDA content in the melon fruit of the 1-MCP treatment group were lower than the control group during the storage period,the CAT and SOD activity in the melon fruit of the 1-MCP treatment group were higher than the control group in storage 3～9 d,the POD,APX activity reached its peak at fourth day,which was 36.50%and 18.97%higher than the control group respectively.It is indicated that ethylene and 1-MCP play an important role in regulating of postharvest senescence of Boxiekexin melon.（3）Research the effects of ethylene and 1-MCP treatment on postharvest cell wall degradation and its enzyme of‘Boxiekexin’melon.The results show during the storage of melon,as the activity of PG increased,the content of pectin decreased and In storage 6～9 d the content of soluble pectin increased obviously.The content of pectin in ethylene treatment group was 32.03%lower than that of the control group storage ninth day.the activity of water soluble pectin and PG was 24.66%and 24.90%higher than that of the control group.The content of pectin in 1-MCP treatment group was 32.03%higher than that of the control group storage ninth day.the activity of water soluble pectin and PG was 24.66%and 24.90%lower than that of the control group.During the storage,the activity of PME,Cellullase andβ-glucosidase ncreased first and then decreased.and the maximum was reached at fifth day,sixth day and seventh day,respectively.The maximum activity of PME,cellulase andβ-glucosidase in the ethylene treatment group was 32.76%,34.51%and 8.2%higher than the control group,respectively,the maximum activity of PME,cellulase andβ-glucosidase in the 1-MCP treatment group was 24.45%,44.43%and 5.5%lower than the control group.The explanation shows that during the storage of fruit,ethylene treatment could induce the increase of the activity of hydrolase in the cell wall of melon,and promote fruit softening,1-MCP can inhibit the degradation of cell wall components by inhibiting the activity of enzyme related to fruit softening,delay fruit softening and senescence. |
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