Classification of Japanese Pear Cultivars by Characteristics of Ethylene Evolution in Ripening Fruits

本文从1989年开始研究日本梨果实乙烯产生量与贮藏特性的关系，并与果实的成熟情况相联系。结果表明，乙烯释放量越大，果实成熟期越早，贮藏性越差。自1991年以来，在国家科学研究资助项目（B）的支持下，我国的一些品种取得了一批优秀的研究成果，乙烯前体物质ACC含量高的品种，其EFE活性也高。但也有一些品种，如二次成，其ACC水平和EFE活性较高，但乙烯产生量很有限，乙烯产生量与液泡膜酶活性之间的关系研究表明，乙烯产生量与液泡膜酶活性之间无相关性，晚熟品种中，乙烯产生量与液泡膜酶活性之间无相关性。由于EFE活性较低，而丙二酸ACC（一种与腐胺相关的多胺）含量较高，乙烯产生量较少。1989年至1993年，对70个日本梨品种进行了研究，根据结果分为4组。

The investigation on the relation between the ethylene production and storage characteristics of Jajpanese pears which connected with the ripening situation of frit was begun in 1989. It was shown that the more the ethylene producted the earlier the ripening period of fruit and the worse the storage characteristics. Since 1991, a lot of outstanding research results have been reached by the supporting of Grant-in-Aid for Scientific Research (B).The cultivars, which had a high content of ACC,the pre-producted substnace of ethylene, always had a high EFE activity. But, there were also some cultivars, such as Nijisseiki, which had higher ACC level and EFE activity but the ethylene production was quite limited.The relationship between the ethylene production and the activity of enzyme in vacuole membrane had been investigated, and the results shown there was no relation between then.In the late maturing cultivars, few ethylene production resulted from the lower activity of EFE and higher content of malonyl ACC which is a kind of polyamine related with putrescine.From 1989 to 1993,70 cultivars of Japanese pears were researched, and they were divided into 4 groups according to the result.