关键词: 柿, 丙烯, 1–甲基环丙烯, EXP, 实时荧光定量PCR

Abstract: In order to further explore the function of expansins（EXP）in the postharvest softening progress of persimmon fruits，‘Fuping Jianshi’was treated with 1-MCP and propylene，respectively. Real- time fluorescent quantitative PCR technology was used to detect the relative expression level of EXP genes in persimmon fruits. The results showed that propylene treatment promoted the softening of persimmon fruits，increased ethylene production and advanced the onset of climactic of ethylene production and accelerated the enzymatic activity of ACS and ACO. However，1-MCP treatment delayed the softening of persimmon fruits，retarded and reduced the peak of ethylene production，inhibited the enzymatic activity of ACS and ACO. Accompanying with fruit ripening，the expression levels of DkEXP3 and DkEXP4 inincreased sharply to maximum within the first 9 d of storage，followed by a control fruit steady decline until the end of storage. Treatment with propylene promoted the expression of DkEXP3 and DkEXP4，increased and advanced the peak of their expression；Treatment with 1-MCP showed a suppression of DkEXP3 and DkEXP4 expression in persimmon fruit，delayed and reduced the peak intensity. The peak expression levels of DkEXP3 and DkEXP4 in，pericarp and core. The results indicated that EXP might play a role in the early stage of postharvest persimmon fruit ripening and softening progress. The expression of EXP genes is tissue-specific and regulated by ethylene. control fruits and 1-MCP treatment fruits appeared earlier than those of the peak of ethylene production rate. The expression levels of EXP genes were different in sarcocarp

Key words: persimmon, propylene, 1-MCP, EXP, real-time quantitative PCR