Plant Protection Research Center, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
Shanghai Jiao Tong University School of Agriculture and Biology, Shanghai 201109, China.
Sci Total Environ. 2024 Dec 1;954:176395. doi: 10.1016/j.scitotenv.2024.176395. Epub 2024 Sep 18.
The widespread application of chiral fungicides as seed-coating agents in agriculture has led to serious residue accumulation in soil, increasingly drawing attention to soil pollution remediation strategies for chiral pesticides. This study explored the role of earthworms and soil microorganisms in selectively accelerating the degradation of penflufen in soil. The results showed that soil microorganisms significantly accelerated penflufen enantiomer degradation, particularly the R-enantiomer. Nocardioides, Variovorax, Arthrobacter, and Pseudomonas were identified as key degrading microorganisms associated with the preferential degradation of the R-enantiomer. The addition of earthworms further significantly enhanced the preferential degradation of the R-enantiomer. Importantly, earthworms markedly promoted the growth and reproduction of the four aforementioned degrading microorganisms in soil treated with enantiomers. Notably, the relative abundance of these degrading microorganisms was significantly higher in R-enantiomer-treated soil with earthworms than in soil treated with the S-enantiomer. Additionally, earthworms significantly increased the relative abundance of degradation genes p450, bphA1, and benA in the soil, especially in the R-enantiomer treated soil. Nocardioides, Variovorax, Arthrobacter, and Pseudomonas were identified as potential hosts for the degradation gene benA. More importantly, twelve strains of penflufen-degrading bacteria were isolated from the treated soil, of which eight belonged to the aforementioned four microorganisms and exhibited a remarkable ability to preferentially degrade the R-enantiomer. This finding highlights the potential of adding earthworms to soil, in conjunction with key degrading microorganisms, which preferentially accelerates penflufen R-enantiomer degradation.
手性杀菌剂作为种子包衣剂在农业中的广泛应用导致其在土壤中严重残留，越来越引起人们对手性农药土壤污染修复策略的关注。本研究探讨了蚯蚓和土壤微生物在选择性加速土壤中 penflufen 降解中的作用。结果表明，土壤微生物显著加速了 penflufen 对映体的降解，特别是 R-对映体。鉴定出诺卡氏菌、鞘氨醇单胞菌、节杆菌和假单胞菌是与 R-对映体优先降解相关的关键降解微生物。添加蚯蚓进一步显著增强了 R-对映体的优先降解。重要的是，蚯蚓明显促进了在处理对映体的土壤中上述四种降解微生物的生长和繁殖。值得注意的是，在有蚯蚓处理的 R-对映体土壤中，这些降解微生物的相对丰度明显高于 S-对映体土壤。此外，蚯蚓显著增加了土壤中降解基因 p450、bphA1 和 benA 的相对丰度，特别是在 R-对映体处理的土壤中。鉴定出诺卡氏菌、鞘氨醇单胞菌、节杆菌和假单胞菌是降解基因 benA 的潜在宿主。更重要的是，从处理过的土壤中分离出了 12 株 penflufen 降解细菌，其中 8 株属于上述四种微生物，它们表现出显著的优先降解 R-对映体的能力。这一发现突出了在土壤中添加蚯蚓与优先加速 penflufen R-对映体降解的关键降解微生物相结合的潜力。
