Pan Dandan, Xu Yue, Ni Yaxin, Zhang Houpu, Hua Rimao, Wu Xiangwei
College of Resources and Environment, Anhui Agricultural University, Key Laboratory of Agri-food Safety of Anhui Province, Hefei, 230036, China; Research Academy of Green Development of Anhui Agricultural University, Hefei, 230036, China.
College of Resources and Environment, Anhui Agricultural University, Key Laboratory of Agri-food Safety of Anhui Province, Hefei, 230036, China.
Environ Pollut. 2022 Jul 1;304:119220. doi: 10.1016/j.envpol.2022.119220. Epub 2022 Mar 28.
The application of exogenous biodegradation strains in pesticide-polluted soils encounters the challenges of migration and persistence of inoculants. In this study, the degradation characteristics, vertical migration capacity, and microbial ecological risk assessment of an enhanced green fluorescent protein (EGFP)-tagged 2-Methyl-4-chlorophenoxyacetic acid (MCPA)-degrading strain Cupriavidus gilardii T1 (EGFP) were investigated in the laboratory and field soils. The optimum remediation conditions for T1 (EGFP) was characterized in soils. Meanwhile, leaching experiments showed that T1 (EGFP) migrated vertically downwards in soil and contribute to the degradation of MCPA at different depths. After inoculation with T1 (EGFP), a high expression levels of EGFP gene was observed at 28 d in the laboratory soil and at 45 d in the field soil. The degradation rates of MCPA were ≥ 60% in the laboratory soil and ≥ 48% in the field soil, indicating that T1 (EGFP) can efficiently and continuously remove MCPA in both laboratory and field conditions. In addition, the inoculation of T1 (EGFP) not only showed no significant impact on the soil microbial community structure but also can alleviate the negative effects induced by MCPA to some extent. Overall, our findings suggested that T1 (EGFP) strain is an ecologically safe resource for the in situ bioremediation of MCPA-contaminated soils.
外源性生物降解菌株在农药污染土壤中的应用面临着接种剂迁移和持久性的挑战。在本研究中，在实验室和田间土壤中研究了增强型绿色荧光蛋白（EGFP）标记的2-甲基-4-氯苯氧基乙酸（MCPA）降解菌株吉氏贪铜菌T1（EGFP）的降解特性、垂直迁移能力和微生物生态风险评估。对T1（EGFP）在土壤中的最佳修复条件进行了表征。同时，淋溶实验表明，T1（EGFP）在土壤中垂直向下迁移，并有助于不同深度处MCPA的降解。接种T1（EGFP）后，在实验室土壤中28天和田间土壤中45天观察到EGFP基因的高表达水平。实验室土壤中MCPA的降解率≥60%，田间土壤中≥48%，表明T1（EGFP）在实验室和田间条件下均能有效且持续地去除MCPA。此外，接种T1（EGFP）不仅对土壤微生物群落结构没有显著影响，而且在一定程度上可以减轻MCPA诱导的负面影响。总体而言，我们的研究结果表明，T1（EGFP）菌株是MCPA污染土壤原位生物修复的生态安全资源。
