Faculty of Resources and Environmental Science, Hubei University, Wuhan 430062, China; Xinjiang Vocation College of Agriculture, Changji, Xinjiang 831100, China.
Faculty of Resources and Environmental Science, Hubei University, Wuhan 430062, China.
Ecotoxicol Environ Saf. 2019 Apr 30;171:771-780. doi: 10.1016/j.ecoenv.2019.01.016. Epub 2019 Jan 22.
Examination of plants with strong Cu tolerance and an understanding of their Cu-tolerance mechanisms are of considerable significance for the remediation of Cu-contaminated soil. Although spinach may be a plant with strong Cu tolerance, the threshold of Cu tolerance in this plant and its physiological response mechanisms to Cu are still unclear. In this study, we examined that the effects of different Cu concentrations on the growth parameters, antioxidant enzyme activities, and photosynthesis of spinach seedlings. The results showed that when treated with a low Cu concentration (100 mg L CuSO), the biomass of spinach seedlings increased, whereas the MDA content, the activities of antioxidant enzymes, P, g and T were not significantly different from those in the control (P > 0.05), and Y(II), qP reached their maximum values, indicating that a low Cu concentration (100 mg L CuSO) had minimal negative effects on the life activities of spinach seedlings. In contrast, when treated with high Cu concentrations (800-1000 mg L CuSO), the total biomass of spinach seedlings was markedly decreased, the MDA contents increased, antioxidant enzyme activities initially increased and then decreased to varying degrees, the contents of chlorophyll, P, T, Fv/Fm, qP NPQ, and Y(II) were all decreased. However the growth of spinach did not terminate, implying that the lethal threshold concentration of Cu for spinach is greater than 1000 mg L CuSO used in this study. In summary, spinach exhibits a high tolerance to Cu and can be considered as an alternative plant for the remediation of Cu-contaminated soils.
研究耐铜能力较强的植物并了解其耐铜机制，对于受铜污染土壤的修复具有重要意义。菠菜可能是一种耐铜能力较强的植物，但该植物的耐铜阈值及其对铜的生理响应机制尚不清楚。本研究探讨了不同铜浓度对菠菜幼苗生长参数、抗氧化酶活性和光合作用的影响。结果表明，低浓度铜（100mg·L-1CuSO4）处理可提高菠菜幼苗的生物量，而 MDA 含量、抗氧化酶活性、P、g 和 T 与对照相比无显著差异（P＞0.05），Y（Ⅱ）、qP 达到最大值，表明低浓度铜（100mg·L-1CuSO4）对菠菜幼苗的生命活动影响较小。相反，高浓度铜（800-1000mg·L-1CuSO4）处理显著降低了菠菜幼苗的总生物量，MDA 含量增加，抗氧化酶活性先升高后降低，叶绿素、P、T、Fv/Fm、qP、NPQ 和 Y（Ⅱ）的含量均降低。但菠菜的生长并未终止，说明本研究中使用的 1000mg·L-1CuSO4 对菠菜的致死阈值浓度大于 1000mg·L-1CuSO4。综上所述，菠菜对铜具有较高的耐受性，可作为一种用于修复铜污染土壤的替代植物。
