三种抗氧化酶在小麦抗干旱逆境中的作用初探

在模拟干旱条件下连续监测了小麦叶片中的3种抗氧化酶：超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)的活力变化．发现在干旱胁迫下，此3种酶的活力均会显著升高，但随胁迫天数的不同，其升高幅度会有所差异。同时测定了经过干旱胁迫后恢复培养的小麦叶片中酶活力的大小，发现仅经过中度诱导胁迫的恢复组酶活力有所下降，其它组均继续升高．作者由此认为：干旱胁迫可诱导小麦叶片中的抗氧化酶活力的升高，这些酶有可能协同作用共同抵抗干旱胁迫造成的氧化伤害，但这种诱导作用并非是无限的，重度胁迫可能对植物造成不可逆的伤害．经同工酶电泳检测发现这种诱导作用仅仅导致酶表达量的增加，并没有产生新的同工酶类型。

The Study of The Function of Three Antioxidant Enzymes in Wheat Leaf Under Drought Stress

The chang tendency of three antioxidant enzymes activity of wheat leaf under drought stress were surveyed . They are superoxide dismatase (SOD) , peroxidase (POD) and catalase (CAT) . The activities of three enzymes raised notably under drought stress , but the raising ranges were different with the different drought days . These enzymes activities which have resumed after lived under drought stress was also surveyed .Only the resume group's activity which had lived under two day's drought stress had a drop , but the others continued raising . It was showed that drought stress can induce POD , SOD , CAT's activities of wheat leaf to raise , and make them resist the oxidative damage cooperating with each other under drought stress . But this induction isn't no restriction . The heavy stress can make a inreversible damage . From the isoenzyme electrophoresis check test ,it was found that this induction didn't inducted some new isoenzyme types but increased the enzymes' expression quantity .