盐胁迫对棉花幼苗保护酶系统活性的影响

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。

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

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.