稀土元素铈缓解镉对菱叶的毒害效应研究  

MODERATING EFFECT OF CERIUM ON CADMIUM TOXICATION OF TRAPA BISPINOSA LEAVES

作　　者：罗玉明[1] 保曙琳[2] 丁秉中[2] 丁小余[2] 杨晋彬[1] 

机构地区：[1]淮阴师范学院生物系,江苏淮安223300 [2]南京师范大学生命科学学院,南京210097

出　　处：《土壤学报》2006年第5期808-813,共6页Acta Pedologica Sinica

基　　金：江苏省教育厅自然科学基金项目(02KJD180009)资助

摘　　要：利用不同浓度的Cd^2＋和不同浓度的Cd^2＋加5mgL^-1Ce^3＋分别处理菱植株，对菱叶中的叶绿素、脯氨酸、保护酶——超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）活性的动态变化进行了研究：实验结果表明：在镉胁迫下，随着镉浓度的上升（0～4mgL^-1）菱叶中叶绿素含量下降，SOD、POD活性和脯氨酸含量在镉低浓度时上升而高浓度时下降，相反，CAT活性在镉低浓度时下降而高浓度时上升。与镉离子单一处理相比，Cd^2＋-Ce^3＋复合处理中的Ce^3＋可提高叶片中叶绿素的含量和SOD、POD的活性，尤其是在1mgL^-1 Cd^2＋加5mgL^-1Ce^3＋复合处理中，POD活性较对照提高了8．33倍。由此表明，5mgL^-1Ce^3＋对低浓度镉引起菱叶片的毒害作用有较为明显的缓解效果。Dynamic changes in content of chlorophll and proline, and activity of protective enzymes such as superoxide （SOD） , peroxidase （POD） and chloramphenicol acetyhransferase （CAT） in the leaves of Trapa bispinosa treated, respectively, with Cd^2＋ at varying rates and Cd^2＋ plus 5 mg L^-1 Ce^3＋ were studied, Results show that chlorophyll contents decreased with increasing Cd^2＋ concentration, while the activity of both SOD and POD, and the content of proline increased when Cd^2＋ concentration was low and decreased when it was high. In contrast, CAT activity decreased when it was low and increased when it was high. Compared with the single ion treatments, the Cd^2＋ ＋ Ce^3 ＋ treatments increased cholorophyll contents, and stimulated activity of SOD and POD, especially, that of the latter, which was 8.33 times higher than its control when the combination was 5 mg L^-1 Ce^3＋plus 1 mg L^-1 Cd^2＋. The results suggest that the addition of 5 mg L^-1 Ce^3＋ can relieve the toxicity of a low concentration Cd^2＋ on leaves of Trapa bispinosa.

关 键 词：稀土元素 铈 缓解 镉胁迫 菱 酶 

分 类 号：X503.23[环境科学与工程—环境工程]