龙葵叶片和根系抗氧化酶对镉胁迫的响应  

Response of antioxidant enzymes in leaves and roots of Solanum nigrum L to cadmium stress

作　　者：史沛丽[1] 张玉秀[1] 柴团耀[2] 

机构地区：[1]中国矿业大学(北京)化学与环境工程学院,北京100083 [2]中国科学院大学生命科学学院,北京100049

出　　处：《中国科学院大学学报（中英文）》2013年第5期608-612,643,共6页Journal of University of Chinese Academy of Sciences

基　　金：国家转基因生物新品种培育重大专项(2009ZX08009-130B);中国科学院知识创新工程重要方向项目---生命科学领域"十二五"基础前沿专项(KSCX2-EW-J-29);中央高校基本科研业务费专项(2010YH05);中国矿业大学(北京)课程建设与教学改革项目(t120301)资助

摘　　要：针对日益严重的土壤镉污染,采用1/2 Hogland营养液研究100μmol/L CdCl2处理1～4 d时龙葵(Solanum nigrum L)叶片和根系的氧化损伤和抗氧化酶活性的变化.结果表明,叶片的MDA和H2O2含量随着Cd胁迫时间的延长而上升,叶片MDA的上升幅度大于根系,根系H2O2的上升幅度大于叶片;叶片和根组织的SOD、CAT、APX和POD活性均随Cd处理时间的延长而升高.说明Cd胁迫诱导龙葵H2O2累积并导致氧化胁迫,抗氧化酶活性升高可能是Cd的解毒机制之一;龙葵叶片H2O2由CAT和APX共同作用清除,而根中H2O2主要由APX清除.Cadmium（Cd） is one of the most toxic environmental pollutants for soils.The seedlings of S.nigrum were exposed to half-strength Hogland solution with 100 μmol/L CdCl2 for 1-4 days,and the activity of antioxidant enzyme in leaves and roots was investigated.The results show that the contents of MDA and H2O2 increase in leaves and roots and the increase of MDA in leaves is larger than that in roots while the increase of H2O2 in roots is larger than that in leaves.Also,the activities of SOD,CAT,APX,and POD in leaves and roots are enhanced with prolonged Cd treatment.It is suggested that the H2O2 accumulation induced by Cd stress leads to oxidative stress and the increase of the oxitioxidant enzyme activity may be one of the mechanisms of Cd detoxification in S.nigrum.H2O2 in leaves may be scavenged by both CAT and APX while the H2O2 in roots may be mainly scavenged by APX.

关 键 词：镉 龙葵 氧化胁迫 抗氧化酶 

分 类 号：X171[环境科学与工程—环境科学]