Landberg Tommy, Greger Maria
Department of Botany, Stockholm University, S-10691 Stockholm, Sweden.
Environ Toxicol Chem. 2002 Dec;21(12):2669-74.
In the complex chemistry of soil, interactions between metals can be expected and these affect the uptake of the metals by the plants. The role of the metal-metal interaction may vary between different plants. This study was performed to investigate if variations exist in the interactions between Cd, Cu, and Zn on toxicity and accumulation of these metals in different clones of Salix viminalis. Two studies were performed. First, to study interaction at uptake, 10 clones with high or low accumulation capacity of Cd, Cu, and Zn, respectively, were treated with 0.3 microM Cd, 0.1 microM Cu, and 3 microM Zn (all three metals at the same time or separately). Second, to study the effect of one of the metals on the sensitivity of the plant to the other metals, three clones with high or low sensitivity to each of the three metals were used in a modified Weibull analysis. Examination of the results shows that interclonal variation exists in effects of metal interaction on metal accumulation and sensitivity exists. The uptake experiment showed that accumulation of Cu was decreased by the other metals, but only in clones with high Cu-accumulating properties because of decreased net uptake of Cu. The accumulation of Zn in roots was increased two- to threefold in all clones in the presence of the other metals because of a decreased translocation of Zn to the shoot. The accumulation of Cd was not changed by the presence of the other metals in any of the clones. The second experiment showed that the effect of interactions between the different metals on metal toxicity was present in all clones but appeared most frequently in the clone with high Zn resistance. Synergistic effects between Cu and Zn in the Zn-resistant clone suggested that this clone had evolved an additional site of toxic action that was absent in the other clones.
在复杂的土壤化学中，可以预期金属之间会发生相互作用，而这些相互作用会影响植物对金属的吸收。金属 - 金属相互作用的作用在不同植物之间可能有所不同。本研究旨在调查镉、铜和锌之间的相互作用在垂柳不同无性系中对这些金属的毒性和积累是否存在差异。进行了两项研究。首先，为了研究吸收过程中的相互作用，分别用0.3微摩尔镉、0.1微摩尔铜和3微摩尔锌（三种金属同时或单独使用）处理了10个分别具有高或低镉、铜和锌积累能力的无性系。其次，为了研究一种金属对植物对其他金属敏感性的影响，在改良的威布尔分析中使用了对三种金属中的每一种具有高或低敏感性的三个无性系。对结果的检查表明，金属相互作用对金属积累的影响存在无性系间差异，并且存在敏感性差异。吸收实验表明，其他金属会降低铜的积累，但仅在具有高铜积累特性的无性系中出现，原因是铜的净吸收减少。在存在其他金属的情况下，所有无性系根中锌的积累增加了两到三倍，这是因为锌向地上部的转运减少。在任何无性系中，其他金属的存在都不会改变镉的积累。第二项实验表明，不同金属之间的相互作用对金属毒性的影响在所有无性系中都存在，但在具有高锌抗性的无性系中出现得最为频繁。锌抗性无性系中铜和锌之间的协同效应表明，该无性系进化出了一个其他无性系中不存在的额外毒性作用位点。
