Cd^2＋、Cu^2＋、Zn^2＋、Pb^2＋对菹草生长胁迫影响及其应答机制

Stress Effect and Response Mechanism of Cd^(2+),Cu^(2+),Zn^(2+) and Pb^(2+) on Potamogeton crispus L. Growth

为探求不同浓度的Cd^(2+)、Cu^(2+)、Zn^(2+)、Pb^(2+)对菹草(石芽)的生长发育的胁迫及其应答机制,对菹草(石芽)的生长状况、叶片的叶绿素、可溶性蛋白质、丙二醛(MDA)含量、抗氧化酶系统等进行了分析。结果如下:Cu^(2+)、Cd^(2+)质量浓度大于0.5 mg/L,植株无法正常生长或存活;Cu^(2+)胁迫下,植株受损程度相对严重。Zn^(2+)、Pb^(2+)质量浓度小于10 mg/L时,菹草仍可以正常生长,但Pb^(2+)胁迫程度比Zn^(2+)较轻。综上,在相同质量浓度下,4种重金属对菹草(石芽)的胁迫强弱依次为Cu^(2+)、Cd^(2+)、Zn^(2+)、Pb^(2+)。本研究为生态修复中水生植物的金属阈值提供了有价值的参考。

To estimate the influence of different heavy metals to the Potamogeton crispus L ., especially the growth and development of its winter buds, the stresses of Cd^2＋,Cu^2＋,Zn^2＋ and Pb^2＋ in different concentrations to the growth and development of winter buds of Potamogeton crispus L . were studied,through the quantitative determination of germinated number of winter buds, chlorophyll of the leaves, soluble protein, malondialdehyde （MDA ）,and antioxidant system. As a result,under the same concentrations,Cu^2＋ had the most obvious effect on physiological and biochemical indexes of the plant. The Cd^2＋ ranked the second and followed by Pb^2＋ and Zn^2＋. The plants cannot grow normally or even survive w ith concentration o f Cu^2＋ or Cd^2＋ higher than 0.5 mg/ L . At the same time,the plants can grow normally under 10 mg/L of Zn^2＋ or Pb^2＋ treatment,which provided effective basis for aquatic plant in the metal threshold for ecological repair.