考察了外源水杨酸处理对水分胁迫下菜豆幼苗叶片的含水量、光合色素含量、电解质外渗率及SOD、POD、CAT活性和根的电解质外渗率及SOD、POD、CAT活性的影响.结果表明:外源水杨酸能减缓水分胁迫下菜豆幼苗叶片含水量和光合色素含量的下降,保持叶片的SOD、CAT和根的SOD、POD、CAT活性,但却增加了叶片和根的电解质外渗率,降低了叶片POD的活性.由此看出,水杨酸可以在一定程度上够缓解水分胁迫对菜豆幼苗造成的伤害. The effects of exogenous salicylic acid on the leaf water content, photosynthetic pigment content, electrolyte exudation, SOD, POD and CAT activities, root exudation rate and SOD, POD and CAT activities under water stress were investigated The results showed that exogenous salicylic acid could reduce the leaf water content and photosynthetic pigment content of the bean seedling under water stress and maintain the activities of SOD, POD and CAT of roots, leaves and roots Electrolyte extravasation rate decreased POD activity of leaf.Accordingly, salicylic acid could alleviate to some extent the harm caused by water stress to bean seedling.