鸭梨、茌梨果实采前乙烯生物合成特性研究

Studies on Ethylene Biosynthetic Characters of Yali and Chili Pears during Pre-harvest Period

鸭梨、茌梨果实均从盛花后１４５天进入呼吸跃变，同时伴随着乙烯释放高峰的出现。鸭梨的乙烯合成酶（ＥＦＥ）活性和氨基环丙烷羧酸（ＡＣＣ）含量高于茌梨，乙烯释放量的峰值是在梨的４倍，两品种果实的ＥＦＥ活性变化与果实的呼吸跃变和乙烯释放量的变化同步，ＡＣＣ含量自盛花后１３５天，一直呈上升趋势。两品种果实内含有亚精胺、腐胺和精胺三种内源多胺，亚精胺与梨果实乙烯生物合成有关。

Ethylene production of Yan and Chili pears (Pyrus bretschneideri Rehd. )from 130 days after full bloom (DAFB) to 145 DAFB remained low. After that,ethylene production increased dramatically until 150 DAFB. The respiratory rate of whole fruits showed a typical pattern of a climacteric fruit during ethylene production peak. The activities of ethylene-forming enzyme (EFE) and 1-aminocyclopropane-1-carboxylic acid (ACC) contents were also very low before ethylene peak. Trends of changes in EFE activities paralleled those of respiratory rate and ethylene production in fruits of the two varieties. Three kinds of polyamines, putrescine, spermidine and spermine, were contained in the pear fruits. Spermidine content in Yan pears was higher than that of Chli pears. It seems that spermidine played an important role in the ethylene biosynthesis of Yali and Chili pears.