School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China.
School of Environment and Resource, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China; Key Laboratory of Solid Waste Treatment and Resource Recycle, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China; Mianyang Boe Optoelectronics Technology Co., Ltd, Mianyang 621010, China.
Sci Total Environ. 2021 Jul 10;777:146118. doi: 10.1016/j.scitotenv.2021.146118. Epub 2021 Mar 2.
Cadmium (Cd) contamination in rice paddy fields constitutes a serious health issue in some parts of China. Here we study the potential for remediation of Cd contaminated alkaline paddy soil with low iron (Fe) and high copper (Cu) background by altering the concentrations of Fe and Cu in the growing media, which has been only seldom considered. We assessed how these two micronutrients (Cu and Fe) affect the absorption and transport of Cd in rice. Adding Cu significantly increased rice biomass and grain yield by reducing root Cd influx and Cd upward transport which, consequently, lowered Cd concentrations in roots, culms and leaves. However, excessive Cu also promoted a relatively higher Cd allocation in grains, especially under Fe deficiency, likely because Cu significantly increased the proportion of bioavailable Cd in leaves. Contrastingly, Fe did not alleviate the toxic effects of Cd on rice growth and yield, but it significantly reduced Cd transfer towards grains, which might be attributed to a sharp decrease in the proportion of bioavailable Cd in leaves. Our results demonstrated that Cd remediation may be achieved through altering Fe and Cu inputs, such that Cd accumulation in rice grains is reduced.
在中国的一些地区，稻田中的镉（Cd）污染构成了一个严重的健康问题。在这里，我们通过改变生长介质中的铁（Fe）和铜（Cu）浓度来研究修复富含铁（Fe）和铜（Cu）背景的碱性稻田中镉（Cd）污染的潜力，而这一点很少被考虑。我们评估了这两种微量元素（Cu 和 Fe）如何影响水稻对 Cd 的吸收和运输。添加 Cu 可通过降低根 Cd 流入和 Cd 向上运输来显著增加水稻生物量和籽粒产量，从而降低根、茎和叶中的 Cd 浓度。然而，过量的 Cu 也促进了相对较高的 Cd 在籽粒中的分配，尤其是在 Fe 缺乏的情况下，可能是因为 Cu 显著增加了叶片中生物可利用 Cd 的比例。相比之下，Fe 并没有减轻 Cd 对水稻生长和产量的毒害作用，但它显著减少了 Cd 向籽粒的转移，这可能归因于叶片中生物可利用 Cd 的比例急剧下降。我们的结果表明，通过改变 Fe 和 Cu 的投入，可以实现 Cd 的修复，从而减少水稻籽粒中的 Cd 积累。
