College of Resources, Sichuan Agricultural University, Chengdu 611130, China.
College of Resources, Sichuan Agricultural University, Chengdu 611130, China.
Ecotoxicol Environ Saf. 2024 Sep 15;283:116779. doi: 10.1016/j.ecoenv.2024.116779. Epub 2024 Jul 30.
Heavy metal pollution of the soil affects the environment and human health. Masson pine is a good candidate for phytoremediation of heavy metal in mining areas. Microorganisms in the rhizosphere can help with the accumulation of heavy metal in host plants. However, studies on its rhizosphere bacterial communities under heavy metal pollution are still limited. Therefore, in this study, the chemical and bacterial characteristics of Masson pine rhizosphere under four different levels of heavy metal pollution were investigated using 16 S rRNA gene sequencing, soil chemistry and analysis of plant enzyme activities. The results showed that soil heavy metal content, plant oxidative stress and microbial diversity damage were lower the farther they were from the mine dump. The co-occurrence network relationship of slightly polluted soils (C1 and C2) was more complicated than that of highly polluted soils (C3 and C4). Relative abundance analysis indicated Sphingomonas and Pseudolabrys were more abundant in slightly polluted soils (C1 and C2), while Gaiella and Haliangium were more abundant in highly polluted soils (C3 and C4). LEfSe analysis indicated Burkholderiaceae, Xanthobacteraceae, Gemmatimonadaceae, Gaiellaceae were significantly enriched in C1 to C4 site, respectively. Mantel analysis showed that available cadmium (Cd) contents of soil was the most important factor influencing the bacterial community assembly. Correlation analysis showed that eight bacterial genus were significantly positively associated with soil available Cd content. To the best of our knowledge, this is the first study to investigate the rhizospheric bacterial community of Masson pine trees under different degrees of heavy metal contamination, which lays the foundation for beneficial bacteria-based phytoremediation using Masson pines in the future.
土壤重金属污染影响环境和人类健康。马尾松是矿区重金属植物修复的良好候选树种。根际微生物可以帮助宿主植物积累重金属。然而，关于其在重金属污染下的根际细菌群落的研究仍然有限。因此，在这项研究中，我们使用 16S rRNA 基因测序、土壤化学和植物酶活性分析，研究了马尾松根际在四种不同重金属污染水平下的化学和细菌特性。结果表明，距矿山排土场越远，土壤重金属含量、植物氧化应激和微生物多样性损伤越低。轻度污染土壤（C1 和 C2）的共生网络关系比高度污染土壤（C3 和 C4）更为复杂。相对丰度分析表明，在轻度污染土壤（C1 和 C2）中，鞘氨醇单胞菌和拟杆菌属更为丰富，而在高度污染土壤（C3 和 C4）中，盖氏菌属和海洋杆菌属更为丰富。LEfSe 分析表明，伯克霍尔德氏菌科、黄杆菌科、真杆菌科、盖氏菌科分别在 C1 到 C4 位点显著富集。Mantel 分析表明，土壤有效态镉（Cd）含量是影响细菌群落组装的最重要因素。相关性分析表明，有 8 个细菌属与土壤有效态 Cd 含量呈显著正相关。据我们所知，这是首次研究不同程度重金属污染下马尾松根际细菌群落，为未来利用马尾松进行有益细菌植物修复奠定了基础。
