梨芽和茎尖多酚氧化酶活性和总酚含量的初步研究

本文研究了梨五个品种３－９月芽和茎尖多酚氧化酶（ＰＰＯ）活性和总酚含量的变化规律。结果表明：鸭梨、苹果梨和南果梨的ＰＰＯ活性在３－９月间呈双峰曲线，其峰值分别出现在５月、４月和５月；苍溪梨和日面红的ＰＰＯ活性呈单峰曲线，其峰值分别出现在６月和８月；五个梨品种ＰＰＯ活性最大峰值大小依次是南果梨＞鸭梨＞日面红＞苹果梨＞苍溪梨。在３－９月中五个梨品种总酚含量均以９月份最高，３月份最低；在３月、４月、６月和８月中，苍溪梨的总酚含量均为五个品种中最低者，而在５月、７月和９月则以日面红的总酚含量最低。

PRELIMINARY STUDIES OF POLYPHENOLOXIDASE ACTIVETIES AND PHENOL CONTENTS IN THE EAR BUDS AND STEM TERMINALS

The regulation of polyphenoloxidase activities (PPO)and phenol contents of five pear varieties during March to September were studied. The results were following.The PPO activities of Yali (Pyrus bretshneideri Rehd),Pingguoli(P. sinkiangensis Yu)and Nanguoli(P. ussuriensis Maxim)buds and stem terminals during March to September showed double-peak curve and their peak values were in May,April and May individually .The PPO activities of Cangxili( P.pyrifolia Nakai) and Rimianhong (P. communis L.)showed single-peak curves and their peak values were in June and August individually The arrange ment of the PPO activities,peak values were: Nanguoli's>Yali's> Rimianhong's>Pingguoli's>Cangxili's. The phenol contents of the five pear varieties in September were highest and those in March were lowest during March to September. Cangxili's phenol contents in March.April,June and August were lowest in the five pear varieties when compared in the same month. In May. July and Septemher,the phenol contents of Rimianhong were lowest in the five varieties.