外源活性氧清除剂对油松幼苗的抗旱性效应

The Effect of Exogenous Active Oxygen Scavenger on Seedling Growth and Drought Resistance of Chinese Pine

采用盆栽PEG处理的方法,研究了水分胁迫条件下外源活性氧清除剂(Vc、VE、MT、a-SA)对油松幼苗生长和抗旱性的影响。结果表明,在水分胁迫条件下,油松幼苗SOD和CAT活性降低,O2.-积累,由此引起膜脂过氧化,MDA含量增高,质膜相对透性增大。外源活性氧清除剂处理后,可提高SOD和CAT活性,明显降低O2.-和MDA含量,提高叶绿素含量、光合速率和水分利用效率,促进油松幼苗的生长和干物质的积累。这些结果表明,干旱条件外源活性氧清除剂能有效地清除活性氧,降低膜脂过氧化程度,恢复或维持植物的正常代谢水平,提高植物的抗旱性。

Effects of exogenous active oxygen scavenger （Vc, VE, MT and a-SA） on seedling growth and drought resistance of Chinese pine （Pinus tabulaeforrnis） under water stress （treated with PEG6000） were studied. The results showed that the activities of SOD and CAT decreased and the content of O2^- increased under water stress. It resulted in membrane lipid peroxidation and the relative permeability of plas- ma membrane and the content of MDA increasing. Under the water stress exogenous active oxygen scavenger gave rise to increasing of SOD and CAT activity and decreasing of O2^- and MDA contents in Chinese pine. The scavengers can raise content of chlorophyll and photosynthetic rate and water use efficiency under drought condition. Therefore it can be concluded that exogenous active oxygen scavenger can scavenge effectively active oxygen and decrease membrane lipid peroxidation and maintain （or recover） normal metabolism of Chinese pine seedling under drought condition, and increase drought resistance of the plant.