有机酸对铅和锌危害的解毒机制研究

Detoxication Mechanism of Organic Acid to Raddish under the Stress of Pb and Zn

采用溶液培养试验和逐步提取法,研究了有机酸对铅、锌毒害的影响及其机制。结果表明:有机酸对重金属植株有一定的解毒作用。对于铅植株,柠檬酸的解毒作用主要是抑制根系吸收,促进铅向茎叶转移,并在茎叶中转变为低活性的形态;酒石酸不改变叶/根比,解毒效应相对较弱。对于锌植株,有机酸没有明显抑制根系的吸收,也没有根和茎叶间活性形态顺序的变化,但锌的毒性相对较小,且酒石酸处理使根和茎叶中的高毒性形态都降低,因而解毒效应也更为明显。

Effect of organic acids on stress of Pb and Zn and its mechanisms was studied by using solution culture tests and sequential extraction method.Results showed that the detoxification of citrate acid to Pb and tartaric acid to Zn was comparatively distinct.For plant treated with Pb,detoxification of citric acid expressed by inhibiting uptake of the root system,improving transformation of Pb to stem and leaves,and transforming into forms of lower activity in the stem and leaves.Tartaric acid did not change the leaf/root ratio,and the detoxification effect was relatively weak compared with the citrate acid situation.For plant treated with Zn,organic acids did not inhibit the absorption of the roots,and also not changed sequence of activity forms for roots and leaves.However,the toxicity of Zn was relatively small,and tartaric acid treatment made higher activity forms of roots and leaves decrease,thus indicating that the detoxification effect of tartaric acid was more significant compared with citrate acid situation.