汞胁迫对小麦幼苗抗氧化酶活性的影响

通过营养液培养实验,研究了小麦幼苗在遭受汞胁迫后,地上部及根系抗氧化酶活性的变化．试验表明:小麦幼苗受到汞胁迫后,地上部及根系的超氧化物歧化酶(ＳＯＤ)的活性均显著增加,过氧化氢酶(ＣＡＴ) 的活性也比对照有所增强,但不如ＳＯＤ酶变化迅速,表明ＳＯＤ酶活性是小麦幼苗遭受汞胁迫时比较敏感的生物标记物．但是,小麦幼苗地上部及根系的丙二醛(ＭＤＡ) 含量仍均比对照显著升高,表明小麦幼苗的膜系统受到了一定程度的破坏．试验同时还反映出,汞胁迫对小麦幼苗根系的影响强于对地上部的影响．

EFFECTS OF MERCURY STRESS ON THE ACTIVITY OF ANTIOXIDANT ENZYMES

The changes of the antioxidant enzyme activity (SOD, CAT) were researched through nutrient solution culture. The results showed: the activity of SOD in shoot and root were significantly en-hanced under mercury stress. The activity of CAT in shoot and root was also improved, but the de-gree was not bigger than that of SOD activity. It showed that the SOD was the sensitive biomarker of wheat seedlings under mercury stress. However the MDA content in shoot and root was significantly higher than that of check group, it suggested that the membrane system were damaged by mercury stress. The experiments also reveled that the root of wheat seedlings was influenced by mercury stress greatly stronger than that of shoot.