棉花黄萎病菌毒素对棉花生化代谢的影响

Effect of V. dahliae Toxin on Biochemical Metabolism of Cotton Seedlings

为明确棉花黄萎病菌毒素对棉花生化代谢的影响,采用棉花黄萎病菌毒素处理棉花黄萎病抗病和感病品种的棉苗后,测定棉株体内超氧化物歧化酶(SOD)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)的活性以及丙二醛(MDA)和木质素含量的动态变化。结果表明,抗病品种陕7191对病菌毒素的抗性显著高于感病品种中棉19;接种毒素后2品种棉苗叶片SOD活性都降低,感病品种降幅高于抗病品种;感病品种POD活性升高较快,到达峰值后迅速下降,而抗病品种POD活性持续上升;2品种PAL活性变化趋势相似,接种后抗病品种活性始终高于感病品种;2品种MDA和木质素含量均增多,感病品种MDA含量的增幅和增量高于抗病品种。

In order to understand the effect of toxin excreted by Verticillium dahliae on biochemical metabolism of cotton seedlings,activities of superoxide dismutase（SOD）,peroxidase（POD）,phenylalanine ammonia lyase（PAL） and the content of malonaldehyde（MDA） and lignin in resistant and susceptible cotton varieties（Shaanxi 7191 and Zhongmian 19） to V.dahliae were determined after inoculation with toxin excreted by V.dahliae to cotton seedlings.The result shows： The resistant cotton variety Shaanxi 7191 had significantly higher resistance to toxin interference than that of susceptible variety Zhongmian 19.The activities of SOD in cotton leaves of both varieties were declined,but the activity of SOD in susceptible variety declined a little more than that in resistant one.The activity of POD in cotton leaves of susceptible one was quickly increased at early period after inoculation with the toxin,and later it was quickly decreased when activity of POD was reached at the maximal level while its activity of resistant variety was steadily increased.The activities of PAL in both two varieties had a similar fluctuant tread and its activity in resistant variety was always higher than that in susceptible one.The content of MDA and lignin in both two varieties was increased,but the amount of its increase in susceptible variety was much higher than that in resistant one.