西瓜不同品种苗期感染枯萎病菌后的生理生化变化

 研究了西瓜不同品种苗期感染枯萎病菌 (FusariumoxysporumSchlecht.f.sp .niveum)后根部细胞的质膜透性、某些酶类和化合物 ,以及光合色素含量的动态变化。结果表明 ,受枯萎病菌侵染后 ,抗病品种克伦生在染病后的短时间内 (48h左右 )能使细胞内MDA、相对电导率、SOD酶和CAT酶的代谢基本恢复到正常状态 ,其自我调节恢复正常状态的能力显著大于感病品种早花 ;抗病品种比感病品种具有保持较高脱氢酶活性的能力 ;抗病品种Vc含量明显高于感病品种 ;抗病品种可溶性糖的相对含量要比感病品种低 ;接菌 1d后抗病品种可溶性蛋白含量高于感病品种 ;抗病品种抑制叶绿素含量下降的能力和保持较高类胡萝卜素含量的能力明显强于感病品种。

Biochemical and Physiological Changes of Different Watermelon Cultivars Infected by Fusarium oxysporum

The dynamic changes in membrane permeability, activities of some enzymes, and contents of some chemical compounds and photosynthetic pigments in root cell of different watermelon cultivars were studied after they were infected by Fusarium oxysporum f. sp. niveum at seedling stage. The results showed that the capacities of self regulating and returning to normal status of 'Kelunsheng', a resistant cultivar, were stronger than 'Zaohua', a susceptible one, in content of malonaldehyde (MDA), relative conductivity, and activities of superoxide dismutase (SOD) and catalase (CAT), when they were infected by F. oxysporum f. sp. niveum. The resistant cultivar maintained higher activity of dehydrogenase, relativly higher content of vitamin C(Vc), and relativly lower content of soluble sugar than the susceptible cultivar. The content of soluble protein was higher in resistant cultivar than in susceptible cultivar after 1 d. The capacities of resistant cultivar in inhibiting chlorophyll deterioration and maintaining higher carotenoid content were significantly stronger than those of susceptible cultivar.