猕猴桃果实乙烯代谢的研究

Studies on Ethylene Metabolism of Kiwifruit after Harvest

刚采收的猕猴桃硬果不产生乙烯,也无 ACC 氧化酶活性,但有少量 ACC 存在。随着果实的软化,乙烯开始出现并很快达到释放高峰,乙烯的释放与 ACC 氧化酶的活性及 ACC的含量变化一致。用外源乙烯或机械伤处理加速了猕猴桃果实内源乙烯释放的原因,是这些处理促进了 ACC 的合成并增加了 ACC 氧化酶的活性。与冷藏相比,气调贮藏强烈地抑制了ACC 氧化酶的活性和乙烯的释放。浸钙处理对猕猴桃果实的乙烯释放、ACC 氧化酶活性及ACC 含量影响不大,因此浸钙处理后减缓猕猴桃果实软化的作用可能是通过其他途径实现的。

Ethylene biosynthesis including ethylene production,ACC oxidase activity.ACC content and treatments which affect its biosyhthesis of‘Qinmei’kiwifruit(Actinidia deliciosa)after harvest were studied.The results showed that there were no distinct releasing of ethylene and activity of ACC oxidase, only small amount of ACC could be determinded at the hardness stage of kiwifruit just after harvest. Thereafter,ethylene appeared and developed a normal released peak which coincided with the increase of ACC oxidase activity and ACC content,and it was accompanied with the softening of kiwifruit.The re- leasing rate of ethylene was higher than the control when the fruit was injuried or treated with exogenous ethylene.because it could stimulate ACC oxidase activity and ACC biosynthesis.CA storage could strong ly inhibit the release of ethylene and ACC oxidase activity.But there was no significant effect on the ethy- lene metabolism during storage when fruit was treated with CaCl_2 after harvest.