College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China.
Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, PR China.
J Hazard Mater. 2021 Jun 5;411:125137. doi: 10.1016/j.jhazmat.2021.125137. Epub 2021 Jan 13.
S-metolachlor (S-ME) is a common chloroacetanilide herbicide. Here, we investigated the effects of S-ME on wheat seedling growth and explored via metabolomics the driver through which S-ME changes the rhizosphere microbiome. The results indicated that 4 mg/kg S-ME had a strong inhibitory effect on plant growth by inducing hydrogen peroxide (HO) levels. The richness of the rhizosphere microbiome markedly decreased after S-ME treatment, although the abundance of some potential beneficial rhizobacteria, such as Rhizobiaceae and Burkholderiaceae, increased suggesting that plants recruited potential beneficial microorganisms to resist S-ME-induced stress. Spearman correlation analysis revealed that Rhizobiaceae and Burkholderiaceae were positively correlated with organic acids secreted by plants after S-ME treatment, implying that potential beneficial microorganisms may be attracted mainly by organic acids. Our results demonstrated the phytotoxicity of S-ME on crop growth and indicated both that S-ME could influence rhizosphere microorganism abundance and that recruitment of potential beneficial microorganisms could be the result of root exudate regulation.
S-甲草胺（S-ME）是一种常见的氯乙酰胺类除草剂。在这里，我们研究了 S-ME 对小麦幼苗生长的影响，并通过代谢组学探索了 S-ME 改变根际微生物组的驱动因素。结果表明，4mg/kg 的 S-ME 通过诱导过氧化氢（HO）水平对植物生长有很强的抑制作用。S-ME 处理后，根际微生物组的丰富度明显下降，尽管一些潜在有益根瘤菌（如根瘤菌科和伯克氏菌科）的丰度增加，这表明植物招募了潜在有益的微生物来抵抗 S-ME 诱导的胁迫。Spearman 相关分析表明，根瘤菌科和伯克氏菌科与 S-ME 处理后植物分泌的有机酸呈正相关，这意味着潜在有益的微生物可能主要被有机酸吸引。我们的结果表明 S-ME 对作物生长具有植物毒性，并表明 S-ME 既能影响根际微生物的丰度，又能通过根分泌物的调节来招募潜在有益的微生物。
