水杨酸对干旱胁迫下豇豆幼苗抗氧化酶活性的影响

Effects of salicylic acid on the anti-oxidant enzymes reactivity of cowpea seedlings under drought stress

研究了外源水杨酸(Salicylic acid,SA)对干旱胁迫下豇豆(Vigna sinensis L.)幼苗叶片抗氧化酶类活性的影响.在干旱胁迫下,经SA和H2O预处理的豇豆幼苗,随胁迫时间的延长,叶片中各种抗氧化酶活性和相对含水量都逐渐下降,但经SA预处理的叶片含水量高于同期水处理叶片含水量,过氧化物酶(POD)、超氧化歧化酶(SOD)和过氧化氢酶(CAT)活性都明显高于同期对照的叶片酶活性.对三种抗氧化酶非变性聚丙烯酰胺凝胶电泳图谱分析可知,在SA预处理和干旱胁迫下,除了CAT没有同工酶条带数目的变化外,SOD和POD都出现了谱带数目的改变.以上结果表明,SA使豇豆幼苗抗氧化酶活性有较大提高,增强了植株对干旱胁迫的抵抗能力.

The effects of exogenous salicylic acid （SA） on activity of anti-oxidative enzymes in leaves of cowpea （ Vigna sinenesis L. ） seedlings under drought stress were studied. The results showed that activity of anti-oxygenase and relative water content in leaves of cowpea was gradually decreased under drought stress after pre-treatrnent with SA and H2O, along with extension of the stress. But after 24 h, water content pretreated by SA was higher than by H2O. In the subsequent progress of stress, the activity of catalase （CAT）, peroxidase （POD） and superoxide dismutase （SOD） pretreated by SA was higher than by H2O. The isozymes made up of CAT, POD and SOD from leaves of cowpea were analyzed by non-denatured polyacrylamide gel electrophoresis and the results showed that the isozymes of SOD and POD were changed in bands pattern excluding CAT. Therefore, these results indicated SA enhanced the activity of anti-oxidative enzymes in leaves of the cowpea seedlings and strengthened the tolerance of cowpea seedlings against drought stress.