中文摘要：

采用水培实验,研究外源添加Fe^2＋和Mn^2＋对水稻幼苗根表铁膜形成、抗氧化酶活性及镉吸收转运的影响。结果表明：（1）添加Fe^2＋使水稻幼苗根表铁膜中铁元素显著增加114.9%（质量分数,下同）,锰和镉元素则分别显著降低了55.2%和42.3%（P〈0.05）;添加Mn^2＋使铁膜中锰元素显著增加180.1%,镉元素则显著降低了18.0%。（2）添加Fe^2＋能显著降低水稻幼苗叶片中活性氧（ROS）,缓解ROS对水稻幼苗的毒害;添加Mn^2＋使得叶片中ROS、超氧化物歧化酶和谷胱甘肽转移酶增加,Mn^2＋处理引起的ROS升高可能起到诱导水稻胁迫应答,缓解镉毒害作用。

英文摘要：

In this study,exogenous Fe^2＋ and Mn^2＋ were used to study the influence of them on rice root iron plaque formation,antioxidase activities and Cd uptake and transportation in hydroponic culture. The results showed that the Fe concentration in root iron plaque was significantly increased by 114. 9%（ mass fraction,the same below） with exogenous Fe^2＋ addition treatment,compared to controls（ P〈0. 05）. However,the Mn and Cd concentration were significantly decreased by55. 2% and 42. 3%,respectively. Exogenous Mn^2＋ addition significantly increased the Fe concentration by 180. 1% in root iron plaque,while the Cd concentration was significantly decreased by 18. 0% comparedto controls. The reactive oxygen species（ ROS） in leaves of rice seedlings was significantly reduced with adding exogenous Fe^2＋ and the toxic effect of ROS on rice seedlings was also reduced. The contents of ROS,superoxide dismutase and glutathione transferase were increased in the leaves with the adding exogenous Mn^2＋. The stress response of rice appeared with the increasing of ROS under the experiments of adding exogenous Mn^2＋ and the toxicity of Cd was also reduced.