外源钕减轻了重金属镉对菹草的毒害作用

Toxic Effect of Cd^(2+) on Potamogeton crispus Alleviated by Exogenous Nd^(3+)

研究了不同浓度钕对菹草镉胁迫的缓解效应。结果表明,单一镉(10mg·L-1)处理降低了菹草叶片抗氧化酶系超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性,丙二醛(MDA)含量升高,可溶性蛋白和叶绿素含量下降。用不同浓度钕处理后,明显减轻了这些症状,抗氧化酶活性均有所提高,与毒害对照相比,SOD、CAT及POD活性分别提高了14.0%～30.0%,8.8%～47.3%,4 6%～15 1%,并减轻了叶绿素和可溶性蛋白的降解,减缓了MDA的积累。随着钕浓度的进一步加大,缓解效应逐渐减弱,钕作用的最适浓度为10～15mg·L-1。

The mitigation of toxic effect of Cd^(2+) on Potamogeton crispus L. by exogenous Nd^(3+) was studied. The results show that when treated with single 10 mg·L^(-1) Cd^(2+) for 5 d, the activity of antioxidase (SOD, CAT, POD) decreased, MDA content increased, chlorophyll and soluble protein content droped in P. crispus. When different concentrations of Nd^(3+) was added into the solution, SOD, POD and CAT activity enhances by 14.0%～30.0%, 8.8%～47.3%, 4.6%～15.1% respectively, the degradation of chlorophyll and protein was alleviated, and accumulation of MDA was reduced in comparison with single Cd^(2+) treatment. But the higher the Nd^(3+) concentration, the worse the relieved action. The optimum dose of Nd^(3+) to Cd^(2+) in P. crispus was ranged from 10～15 mg·L^(-1).