Cd单一及Cd、Zn复合污染对玉米幼苗生理特性的影响

Effects of Cd Single and Cd,Zn Combined Pollution on Physiological Characteristics of Corn Seedling

采用溶液培养法,研究不同浓度Cd单一及Cd+Zn(0.50mmol/L)复合污染对玉米叶绿素、脯氨酸、MDA含量及SOD、POD、CAT活性的影响.结果表明Cd对叶片的影响比根部明显,随着Cd浓度的增加,叶片中叶绿素含量降低、脯氨酸含量增加,有效的活性氧自由基清除系统的平衡被打破,叶片中MDA含量增加;而根部的活性氧自由基清除系统的平衡未被打破,MDA含量保持在一个较低的水平.Zn能部分缓解Cd对玉米体内活性氧消除系统的毒害作用,降低MDA含量,但Zn和Cd共同对叶绿素的含量表现出抑制作用.

The effects of different concentrations of Cd and Cd＋Zn （0. 50 mmol/L） combined pollution on chlorophyll, proline, MDA content and SOD, POD, CAT activity in corn seedling were studied using the solution culture. The results indicated that the effects of Cd stress on leaves were more significant than that on roots. With the increase of Cd concentration,chlorophyll content decreased and proline content increased. The active oxygen elimination system was imbalanced in leaves and MDA content increased. But in roots, the active oxygen elimination system was still balanced,and MDA content kept in a low level. The addition of Zn （0.50 mmol/L） could partly alleviate the toxicity of Cd, and decrease the MDA content. But Cd and Zn compound pollution decreased the chlorophyll content.