渗透胁迫对杧果叶片活性氧伤害的影响

Effect of osmotic stress on active oxygen damage of leaves in mango

杧果叶片经渗透胁迫处理后,叶水势ΨL下降,O2-. 产生速率和MDA含量增加,SOD、POD和CAT的活性水平与O2-. 和MDA的变化相一致。结果表明,杧果叶片的渗透胁迫损伤,是由O2-. 引发的膜脂过氧化,致使MDA含量增加,破坏细胞膜系统所致。渗透胁迫处理过程中,GSH和AsA含量下降。

Leaves of mango (Mangifera indica) were treated with different osmotic stress. The results showed that the water potential of leaves decreased with the increasing of osmotic stress, the generation rate of superoxides and the content of MDA increased with the increasing of osmotic stress. The generation rate of O2-. and the content of MDA was up to the peak when the osmotic stress reached 1.25Mpa and the activities of SOD, POD and CAT corresponded to the change of O2-. and the content of MDA. The contents of GSH and AsA decreased rapidly with the increasing of osmotic stress. The finding revealed that the cell damage of leaves under osmotic stress was caused by membrane lipid peroxidation first, resulting in the increasing of MDA content and the cytoplasmic system destruction.