柿树受日本龟蜡蚧危害后丙二醛及保护酶变化的研究

Research on Active Oxygen and Protected Enzymes in Persimmon Harmed by Japanese Wax Scale

柿树受日本龟蜡蚧危害后,分别以轻微受害(对照)、中等受害、严重受害三个等级研究了柿树体内丙二醛及超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)的动态变化过程,旨在揭示树体保护酶与树体抗虫作用的关系。结论如下:树体内丙二醛(MDA)含量受害区有两个增高峰,分别在4月底和6月底,丙二醛含量与受害程度成正相关。超氧化物歧化酶在中等受害区形成两个高峰期,第一个高峰期为4月底至5月中旬,第二个高峰期为7月。严重受害区在前期与对照相当,7月达到高峰,为三区之最,一直到树体生长后期,严重受害区都与对照和中等受害区保持着显著的差异,受害程度越重,SOD活性越强,有利于柿树对害虫的防御。过氧化物酶在受害区5月为第一个高峰期,第二个高峰期是7月。过氧化氢酶活性在受害区柿树生长中后期出现高峰,7月初中等受害区CAT活性最大,而严重受害区出现高峰时间较迟在7月下旬,但持续增长时间更长。

The changed plocess of MDA, SOD, POD and CAT in the body of persimmon, which was harmed by Japanese wax scale, was researched on the scales of lightly （check） and moderate and heavily damaged degrees in order to show the relations between the protected enzymes in persimmon and resistance-insect. The results as follows： The content of MDA had two peaks in the damaged persimmons, at the end of April and at the end of June; the content of MDA corresponded to the damaged degree. SOD formed two peaks in the moderate damaged persimmons： the first peak was at the end of April to mid - May; the second peak was in July. The heavily damaged persimmons corresponded to the comparative ones in the early period, it reached peak in July and was the highest in the three areas. Heavily damaged persimmons had obvious difference with the moderate and the comparative until the later period of tree growing. The more damage the persimmons suffered, the more activity of SOD the trees had. The first larger period of the activities of POD was in May in the damaged persimmons; the second one was in July. The more damages the persimmons suffered, the more activities of peroxide enzymes they had. The activity of CAT in damaged persimmons was larger at middle and later stages. The activity of CAT was almost same in the different damaged persimmons from April to May. It was the highest in the moderate damaged persimmons at the beginning of July while it was the highest in the heavily damaged persimmons at the end of July, which continued to increase for a long time.