Department of Agronomy, National Chiayi University, Taipei 60004, Taiwan, ROC.
National Museum of Natural Science, Taichung 40453, Taiwan, ROC.
Ecotoxicol Environ Saf. 2014 Jun;104:36-42. doi: 10.1016/j.ecoenv.2014.02.008. Epub 2014 Mar 12.
The phytotoxic effects of excess copper (Cu) on grapevines (Vitis vinifera L. var. Kyoho) were examined, both from macroscopic and microscopic perspectives, by using a fifteen-day hydroponic experiments. The influence of magnesium (Mg) on Cu phytotoxicity to, and accumulation and translocation in grapevines was also observed. For phytotoxicity effect, results showed that a relative low median growth inhibition level of Cu was found for grapevine roots (0.809-3.671μM). Moreover, Cu toxicity was significantly alleviated by Mg treatment at Mg(2+) activity between 0.15 and 2.01mM. For accumulation and translocation effects, results indicated that competition for binding sites between Cu and Mg occurred for roots; however, Mg and Cu levels in stems and leaves were not affected by solution metals concentration. At Cu concentration less than 1μM, the translocation of Cu was decreased significantly for the highest Mg treatment; at Cu concentrations greater than 5μM, no obvious change was observed in leaf TF value between Mg treatments, while an increasing trend of stem TF value was observed with increasing Mg. These results suggest that the toxic effect resulted from metals depend not only on the competition of coexistent cations for plasma membrane surface, but also on the transport and distribution of toxic metals in physiological active sites in plants.
采用为期 15 天的水培实验，从宏观和微观角度研究了过量铜（Cu）对葡萄（Vitis vinifera L. var. Kyoho）的植物毒性效应。还观察了镁（Mg）对 Cu 对葡萄的植物毒性、积累和迁移的影响。对于植物毒性效应，结果表明，葡萄根的相对较低的中值生长抑制水平（0.809-3.671μM）。此外，在 0.15 至 2.01mM 的 Mg(2+)活性下，Mg 处理显著减轻了 Cu 毒性。对于积累和迁移效应，结果表明，Cu 和 Mg 之间在根部存在结合位点的竞争；然而，Mg 和 Cu 水平在茎和叶中不受溶液金属浓度的影响。在 Cu 浓度低于 1μM 时，最高 Mg 处理显著降低了 Cu 的迁移；在 Cu 浓度大于 5μM 时，Mg 处理之间叶片 TF 值没有明显变化，而茎 TF 值呈增加趋势。这些结果表明，金属的毒性效应不仅取决于共存阳离子对质膜表面的竞争，还取决于植物生理活性部位中有毒金属的运输和分布。
