盐胁迫对棉花幼苗保护酶系统活性的影响

Effects of Salt Stress on the Activity of Protective Enzymes in Cotton Seedling

在盐胁迫条件下，对耐盐性不同的２个陆地棉品种幼苗子叶和胚根的保护酶活性变化进行了比较。结果表明：盐胁迫条件下，２个品种ＰＯＤ，ＳＯＤ活性在胚根部位均有所增强，子叶部位则有不同程度的降低；耐盐性较强的枝棉３号在盐胁迫初期胚根部位ＰＯＤ、ＳＯＤ活性上升幅度大于耐盐性较弱的鲁棉１０２４，但随盐胁迫时间延长，枝棉３号ＰＯＤ、ＳＯＤ活性又开始下降，而鲁棉１０２４则持续上升；枝棉３号子叶部位ＰＯＤ、ＳＯＤ活性经调节之后均接近对照，而鲁棉１０２４的ＰＯＤ、ＳＯＤ活性则表现为持续下降。结果提示出棉花幼苗对盐渍的适应调节主要表现在根部，但棉花品种耐盐性差异则表现在子叶部位。

The changes of the protective enzyme activity in roots and cotyledons were compared between two different salt tolerance cotton cultivars (Salt-tolerant cultivar zhimiah 3 and non-tolerant cultivar Lumian 1024). The results showed that both POD and SOD activities in roots of two cultivars raised under salt stress, and declined in cotyledons of two cultivars;At primary stage of salt stress, the higher POD. SOD activity could be maintained in roots of Zhimian 3 than Lumain 1024. However, at the late stage of salt stress, the POD. SOD activity significantly declined in Zhimian 3 and gradually rose in Lumian 1024; The POD. SOD activity was almost the same between cotyledon of Zhimian 3 under salt stress and control, and the POD. SOD activity gradually declined in cotyledon of Lumian 1024. As a result it was mainly influenced by roots that cotton seedling adapted to salt stress, but salt tolenance of cotton variety was influenced by cotyledons.