Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, College of Natural Resources and Environmental Science, Zhejiang University, Hangzhou, 310058, China.
Department of Agricultural Sciences, La Trobe University, Bundoora, Melbourne, VIC, 3086, Australia.
Environ Sci Pollut Res Int. 2019 Jan;26(3):2531-2546. doi: 10.1007/s11356-018-3736-x. Epub 2018 Nov 24.
The chiral herbicide imazethapyr (IM) is frequently used to control weeds in soybean fields in northeast China. However, the impact of IM enantiomers on microbial communities in soil is still unknown. Genetic markers (16S rRNA V3-V4 regions) were used to characterize and evaluate the variation of the bacterial communities potentially effected by IM enantiomers. Globally, the bacterial community structure based on the OTU profiles in (-)-R-IM-treated soils was significantly different from those in (+)-S-IM-treated soils, and the differences were enlarged with the treatment dose increasing. Interestingly, the Rhizobiaceae family and several other beneficial bacteria, including Bradyrhizobium, Methylobacterium, and Paenibacillus, were strongly enriched in (-)-R-IM treatment compared to (+)-S-IM treatment. In contrast, the pathogenic bacteria, including Erwinia, Pseudomonas, Burkholderia, Streptomyces, and Agrobacterium, were suppressed in the presence of (-)-R-IM compared to (+)-S-IM. Furthermore, we also observed that the bacterial community structure in (-)-R-IM-treated soils was more quickly restored to its original state compared with those in (+)-S-IM-treated soils. These findings unveil a new role of chiral herbicide in the development of soil microbial ecology and provide theoretical support for the application of low-persistence, high-efficiency, and eco-friendly optical rotatory (-)-R-IM.
手性除草剂咪草烟（IM）常用于控制中国东北大豆田中的杂草。然而，IM 对映体对土壤微生物群落的影响尚不清楚。遗传标记（16S rRNA V3-V4 区）用于表征和评估潜在受 IM 对映体影响的细菌群落的变化。总体而言，基于 (-)-R-IM 处理土壤中 OTU 图谱的细菌群落结构与 (+)-S-IM 处理土壤中的结构有显著差异，且随着处理剂量的增加而扩大。有趣的是，与 (+)-S-IM 处理相比，根瘤菌科（Rhizobiaceae）家族和其他几种有益细菌，包括慢生根瘤菌（Bradyrhizobium）、甲基杆菌（Methylobacterium）和类芽孢杆菌（Paenibacillus），在 (-)-R-IM 处理中强烈富集。相比之下，在 (-)-R-IM 存在下，致病性细菌，包括欧文氏菌（Erwinia）、假单胞菌（Pseudomonas）、伯克霍尔德菌（Burkholderia）、链霉菌（Streptomyces）和根癌农杆菌（Agrobacterium）受到抑制。此外，我们还观察到 (-)-R-IM 处理土壤中的细菌群落结构比 (+)-S-IM 处理土壤中的更快恢复到原始状态。这些发现揭示了手性除草剂在土壤微生物生态学发展中的新作用，并为低持久性、高效、环保光学旋光性 (-)-R-IM 的应用提供了理论支持。
