油桐品种抗黑斑病生理生化机制研究——Ⅲ.品种抗性与多酚氧化酶之关系

A Study on the Physiological and Biochemical Mechanism of Aleurites fordii Varieties Resisting Black Spot (Ⅲ) The relationship between variety resistance and polyphenol oxidase

在健叶(果皮)上,多酚氧化酶活性、比活性均不反映品种间抗病性的规律性变化,但病叶(果皮)的多酚氧化酶活性、比活性都是抗病品种比感病品种高;分析了离病斑不同距离组织的多酚氧化酶活性及比活性,发现抗病品种在病斑近处酶活、比活大幅度提高,但波及范围较窄,感病品种在病斑近处酶活、比活提高幅度较小,但影响范围较广;病叶多酚氧化酶同工酶抗病品种为2—3条谱带,感病品种仅为1条谱带。

The polyphenol oxidase activities (POA) and specific activities (SA)in the healthy leaves and peel do not show the regular changes of disease resis-tance among Aleurites ford ii varieties. In the diseased leaves and peel, however,POA and SA of resistant varieties are higher than those of susceptible ones. Af-ter POA and SA in the tissues at the different distances from spots have beenanalyzed, it is found that near the spots POA and SA of resistant varieties in-crease on a large scale while the range involved is comparatively narrow and nearthe spots POA and SA of susceptible varieties increase just on a smaller scalewhile the range involved is relatively extensive. In the diseased leaves, there are2--3 bands of polyphenol oxidase isozyme for the resistant varieties and only onefor the susceptible varieties.