盐度对互花米草氧化和抗氧化系统的影响

Effects of Salinity on Oxidative and Antioxidative System of Spartina alterniflora

研究了互花米草幼苗在不同盐度培养下,其叶片超氧阴离子(O2-)、过氧化氢(H2O2)、丙二醛(MDA)、谷胱苷肽(GSH)、抗坏血酸(AsA)、超氧化物歧化酶(SOD)、过氧化物酶(POD)、抗坏血酸过氧化物酶(AsA-POD)、过氧化氢酶(CAT)等氧化和抗氧化指标的变化.结果表明,各指标在不同盐度间都有显著差异(p<0.05).经研究发现,随着盐度的升高,O2-含量有所下降,H2O2含量稍有上升,膜脂过氧化产物MDA含量虽有上升,但幅度很小且保持在一个较低的水平,而各抗氧化保护酶的活性和小分子抗氧化剂GSH和AsA的含量都升高了,且都保持在较高的水平,说明互花米草是一种耐盐性较高的滨海盐沼植物,在盐胁迫下,其体内的抗氧化保护酶和抗氧化剂在清除O2-的过程中发挥了重要的作用.

In this paper,the changes of H_2O_2,O^-_2,MDA,GSH,AsA contents and SOD,POD,AsA-POD,CAT activities for Spartina alterniflora seedlings under different salinity treatments were studied.The results showed that all indices changed significantly among various salinities (p<0.05).It was also found that the content of O^-_2 declined with the increase of salinity,while that of H_2O_2 increased slightly.The content of MDA,a product of lipid peroxidation,also went up slightly and remained a relatively-low level,while the activities of all antioxidative enzymes and the contents of antioxidant GSH and AsA all enchanced to a quite high level with increasing salinity.All these results implied that Spartina alterniflora was a kind of salt-marsh plant with high salt tolerance,and the antioxidative enzymes and antioxidants in vivo played important roles in scavenging O^-_2 under salt-stress.