Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
Chemosphere. 2020 May;247:125965. doi: 10.1016/j.chemosphere.2020.125965. Epub 2020 Jan 20.
Phosphorous (P) fertilization is an important agronomic practice, but its role in enhancing phytoremediation efficacy and mediating detoxification has rarely been reported in environmental remediation studies. In this study, a pot experiment was undertaken to assess: firstly, the effect of P on phytoextraction of Cu by Ricinus communis L.; secondly, the potential mechanisms by differentiating the effects of the plant from that of P fertilizer (Ca(HPO)); and thirdly, the role of P in physiological detoxification. Results showed that the application of P fertilizer significantly (p ≤ 0.05) increased the plant biomass as well as the Cu concentrations in plant tissues. This enhanced the phytoremediation efficiency represented by the total Cu extraction (up to 121.3 μg Cu plant). Phosphorous (P) fertilizer led to a negligible decline in soil pH (0.2 units) but significantly (p ≤ 0.05) reduced the concentrations of soil available in Cu and Fe, due to the formation of insoluble Cu/Fe-phosphate precipitates. Nevertheless, P fertilizer still improved the accumulation and extraction of Cu by R. communis, most likely attributable to the Fe-deficiency induced by applied P fertilizer. Moreover, the application of P fertilizer revealed a significant reduction in MDA, and a profound (p ≤ 0.05) elevation in the amount of photosynthetic pigments, GSH and AsA, along with the enhanced activities of antioxidative enzymes (SOD, POD, and CAT). In this way, Cu toxicity was alleviated. P fertilizers not only enhance the phytoremediation efficiency of Cu-contaminated soils by R. communis, but they also facilitate detoxification, which improves our understanding of the role of P in phytoremediation technologies.
磷（P）施肥是一种重要的农业实践，但在环境修复研究中，很少有报道称其在增强植物修复效果和介导解毒方面的作用。在这项研究中，进行了盆栽实验，以评估：首先，P 对蓖麻（Ricinus communis L.）对 Cu 的植物提取的影响；其次，通过区分植物和 P 肥料（Ca（HPO）的作用来区分植物和 P 肥料（Ca（HPO）的潜在机制；第三，P 在生理解毒中的作用。结果表明，施用 P 肥料显著（p≤0.05）增加了植物生物量以及植物组织中的 Cu 浓度。这提高了以总 Cu 提取量（高达 121.3μg Cu plant）表示的植物修复效率。P 肥料导致土壤 pH 值（0.2 个单位）略有下降，但由于形成了不溶性的 Cu/Fe-磷酸盐沉淀，显著降低了土壤中有效 Cu 和 Fe 的浓度（p≤0.05）。尽管如此，P 肥料仍然提高了 R. communis 对 Cu 的积累和提取，这很可能归因于施用 P 肥料引起的 Fe 缺乏。此外，施用 P 肥料导致 MDA 显著减少，同时显著增加了光合色素、GSH 和 AsA 的含量，并增强了抗氧化酶（SOD、POD 和 CAT）的活性。这样，Cu 毒性得到缓解。P 肥料不仅通过 R. communis 提高了 Cu 污染土壤的植物修复效率，而且还促进了解毒作用，这加深了我们对 P 在植物修复技术中的作用的理解。
