干旱与氧化胁迫对小麦根氧化还原状态和叶片ABA积累的影响

Effects of Drought and Oxidative Stresses on Redox Status in Wheat Roots and ABA Accumulation in Wheat Leaves

通过分析一氧化氮(nitric oxide,NO)、活性氧(reactive oxygen species,ROS)和干旱胁迫对小麦根氧化还原状态和叶片脱落酸(abscisic acid,ABA)积累的影响,探讨了干旱胁迫下NO和H2O2调节ABA合成的可能机制。结果表明:干旱胁迫处理初期小麦根还原型谷胱甘肽含量降低、抗氧化酶活性发生振荡变化,细胞氧化还原状态向氧化型转变。NO和H2O2能模拟干旱胁迫的作用使细胞状态向氧化型转变,还可以使小麦叶片ABA积累量上升。干旱胁迫下NO和H2O2对ABA合成的调节作用可能是通过调节细胞氧化还原状态进行。

The study presented in this paper probed the effects of nitric oxide,reactive oxygen species and drought stress on redox status in the roots and ABA accumulation in the leaves of wheat as well as the mechanism by which nitric oxide and reactive oxygen species regulated ABA synthesis under drought stress. The results indicated that in the beginning period of drought stress,the roots showed a decreased reductive glutathione content,a fluctuated activity of antioxidative enzymes,and a cellular transition from reductive status to oxidative status. NO and H2O2 could lead to the cellular transition towards oxidative status by simulating the effect of drought stress,and they could also increase ABA accumulation in wheat leaves. Under drought stress,NO and H2O2 probably exerted their regulating effect on ABA synthesis by regulating cellular redox status.