ABSTRACT

To assess the effects of brassinolide (BR) on the growth and phytoremediation ability of cadmium (Cd) accumulator plants, different BR concentrations were applied to emerged accumulator plant Nasturtium officinale growing in Cd-contaminated soil. Brassinolide application increased the biomass, photosynthetic pigment content, and antioxidant enzyme activity of N. officinale. When N. officinale was treated with 1.5 mg L⁻¹ of BR, the highest shoot biomass was obtained, recording an increase of 26.06%, compared to the control. In addition, BR treatment decreased the Cd contents in the shoots of N. officinale, and the BR concentrations of 0.5, 1.0, 1.5, and 2.0 mg L⁻¹ decreased the Cd content in shoots by 10.49%, 12.11%, 20.13%, and 17.23%, respectively, compared to the control. Brassinolide treatment also slightly inhibited the transportation of Cd from the roots to shoots. The findings revealed that BR had no significant effects on the Cd extraction amounts by stems, leaves, and shoots of N. officinale. However, BR promoted the growth of N. officinale and inhibited the Cd uptakes in the above-ground part of N. officinale. Thus, N. officinale could be used as a wild vegetable in the Cd-contaminated soil, although not suitable for phytoextraction as an accumulator plant.

摘要

为了评估油菜素内酯 (BR) 对镉 (Cd) 富集植物生长和植物修复能力的影响，将不同的 BR 浓度应用于生长在镉污染土壤中的出苗富集植物金莲花。油菜素内酯的应用增加了铁皮的生物量、光合色素含量和抗氧化酶活性。当N. officinale用 1.5 mg L ^-1的 BR 处理时，获得了最高的枝条生物量，与对照相比增加了 26.06%。此外，BR处理降低了铁皮新梢Cd含量，BR浓度分别为0.5、1.0、1.5和2.0 mg L ^-1与对照相比，新梢中镉含量分别降低了 10.49%、12.11%、20.13% 和 17.23%。芸苔素处理也略微抑制了镉从根部到芽的​​运输。结果表明，BR对铁皮茎、叶和芽的Cd提取量没有显着影响。但BR促进了铁皮的生长，抑制了铁皮地上部分对Cd的吸收。因此，N. officinale可用作 Cd 污染土壤中的野菜，但不适合作为植物提取植物。