盐胁迫对小麦萌发期幼苗抗氧化酶系统的影响

Effects of Salt Stress on the Activities of Antioxidant Enzymes in Wheat Seeding

为了解盐胁迫对小麦萌发期幼苗抗氧化酶系统的影响,选择不同抗盐性的小麦品种德抗961和泰山9818,研究了盐胁迫下小麦萌发期幼苗3~13 d抗氧化酶活性的变化。结果表明：随着盐胁迫浓度的增大,德抗961幼苗的SOD,POD和APX的活性增加,CAT活性7天后也增加,泰山9818幼苗这几个酶的变化趋势存在差别。随着胁迫时间的延长,2品种的SOD和APX活性各处理都表现为随着盐胁迫时间的延长而降低,POD上升,CAT先升后降。推测超氧阴离子在前期积累较多,而过氧化氢在后期较多。在整个胁迫过程中,抗盐品种的POD和CAT活性一直高于普通品种,可见,POD和CAT与抗盐性联系密切。

In this study,two wheat cultivars（DK961 and TS9818） were selected to study the effects of salt stress on the antioxidant enzymes of cultured wheat seedling of 3-13 days.The results showed that the activities of SOD,POD and APX enhanced with the increase of salt stress level and CAT activity also improved after seven days of culture in DK961.As to TS9818,the influence of salt stress on antioxidant enzymes varied with enzyme types.With the extension of salt stress time,the activities of SOD and APX declined,while POD activity increased,and CAT activity increased in early time of salt stress and decreased in the later culture time for the two wheat cultivars in this study,which suggested that there was more superoxide anion accumulation in prophase and more hydrogen peroxide accumulation in anaphase during salt stress time.The activities of POD and CAT in salt resistant wheat cultivar DK961 were much higher than those in salt sensitive wheat cultivar TS9818 under salt stress conditions or in CK,which indicated that the activities of POD and CAT were closely related to wheat salt resistance.