Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410221, China.
Xiaoliang Research Station for Tropical Coastal Ecosystems, and the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; Department of Chemistry and Life Science, Xiangnan University, Chenzhou 423000, China.
Ecotoxicol Environ Saf. 2022 Nov;246:114196. doi: 10.1016/j.ecoenv.2022.114196. Epub 2022 Oct 15.
Pfaffia glomerata is a candidate for phytoremediation due to its high biomass and high bioaccumulation efficiency of multiple heavy metals. It is essential to further evaluate its tolerance, absorption, transfer, and distribution to multiple heavy metals. In the current study, we evaluated the tolerance, absorption, transfer, and distribution of P. glomerata in a Cd/Pb/Cu/Zn combined-contaminated environment by two hydroponic experiments. The results demonstrated that P. glomerata was not affected by Cd/Pb/Cu/Zn exposure, except for the 50 μM Cd/Pb/Cu/Zn treatment, which significantly decreased the stem biomass. In a single Cd, Pb, Cu, and Zn exposure, the root of P. glomerata absorbed Cd/Pb/Cu/Zn in the order of Cd > Zn > Pb > Cu. Almost all Pb and Cu accumulated in the plant roots and were hardly transferred to the aboveground parts. Therefore, the order of total Cd/Pb/Cu/Zn extraction of a single plant in multiple Cd/Pb/Cu/Zn exposures at the same concentration was Cd > Zn > Pb > Cu. The bioconcentration factor (BCF) of Cd and Zn in roots, stems, and leaves increased with the concentration of Cd and Zn in the solution, and was > 1. In contrast with Cd and Zn, the BCFs of Cu and Pb in the stems and leaves were < 1. The element distribution of Pb, Cu, Zn, and Mn in the stem of P. glomerata was dispersed, indicating that the stem of P. glomerata does not have a detoxification mechanism for distributing metals to the area of low biological activity. The total amount of tartaric acid, critic acid, and DOC secreted by P. glomerata roots decreased with the increase in Cd/Pb/Cu/Zn exposure. However, further investigation is needed to unravel the interaction between the LMWOAs secreted by the root of P. glomerata and heavy metals.
巨叶巴布麻是一种候选的植物修复物种，因为它具有较高的生物量和对多种重金属的高生物富集效率。进一步评估其对多种重金属的耐受性、吸收、转运和分配能力是很有必要的。在本研究中，我们通过两个水培实验来评估巨叶巴布麻在 Cd/Pb/Cu/Zn 复合污染环境中的耐受性、吸收、转运和分配。结果表明，除了 50μM 的 Cd/Pb/Cu/Zn 处理会显著降低茎生物量外，Cd/Pb/Cu/Zn 暴露对巨叶巴布麻没有影响。在单一 Cd、Pb、Cu 和 Zn 暴露下，巨叶巴布麻的根吸收 Cd/Pb/Cu/Zn 的顺序为 Cd > Zn > Pb > Cu。几乎所有的 Pb 和 Cu 都积累在植物根部，难以转移到地上部分。因此，在相同浓度的多种 Cd/Pb/Cu/Zn 暴露下，单一植物对 Cd/Pb/Cu/Zn 的总提取量顺序为 Cd > Zn > Pb > Cu。在根、茎和叶中，Cd 和 Zn 的生物浓缩因子（BCF）随着溶液中 Cd 和 Zn 浓度的增加而增加，且均>1。与 Cd 和 Zn 不同，Cu 和 Pb 在茎和叶中的 BCFs<1。巨叶巴布麻茎中 Pb、Cu、Zn 和 Mn 的元素分布较为分散，表明巨叶巴布麻茎没有将金属分配到生物活性低的区域的解毒机制。巨叶巴布麻根分泌的酒石酸、柠檬酸和 DOC 的总量随着 Cd/Pb/Cu/Zn 暴露的增加而减少。然而，需要进一步研究来阐明巨叶巴布麻根分泌的低分子量有机酸与重金属之间的相互作用。
