近年来，二苯醚类除草剂氟磺胺草醚的大量使用严重污染农田土壤，造成后茬敏感作物药害，已成为一个亟待解决的问题。降解菌株Bacillus sp.Za的硝基还原酶DnrA可高效转化多种二苯醚类除草剂，有效去除作物药害。本申请拟在此研究的基础上，将菌株Za接种到氟磺胺草醚污染土壤中进行人工修复，评价除草剂残留的微生物修复效果；建立氟磺胺草醚在土壤中的降解途径；跟踪菌株Za在土壤中的定殖、存活和关键酶基因表达的过程；分析参与除草剂降解的土著微生物种类及作用机制；分离参与降解的土著微生物并构建功能菌群；解析土著微生物群落结构的演替规律与响应机制。本项目研究结果可阐明投加降解菌株Za修复氟磺胺草醚残留污染土壤的具体过程与机制，为利用微生物修复技术去除土壤中氟磺胺草醚残留提供更多的理论依据与方法。

In recent years, the extensive use of the diphenyl ether herbicide fomesafen has polluted the farmland soil and caused residual phytotoxicity to the rotation of sensitive crops, which have become an urgent problem to be solved. The nitroreductase DnrA of the degrading strain Bacillus sp. Za could efficiently transform a variety of diphenyl ether herbicides and effectively remove crop phytotoxicity. On the basis of our previous studies, the strain Bacillus sp. Za will be inoculated into the fomesafen contaminated soil for bioremediation. In this project, we will evaluate the removal effect of fomesafen residues in the soil; establish the degradation pathway of fomesafen; track the processes of colonization, survival and expression of gene dnrA in the soil; analyze the species and mechanism of indigenous microbial involved in fomesafen degradation；isolate the functional indigenous microbial and construct the mixed flora; reveal the changes of indigenous microbial community structure and the response mechanisms. The results of this project could analyze the processes and mechanisms of the bioremediation of fomesafen contaminated soil, and provide more theories and methods for the use of microbial bioremediation technology to remove fomesafen residues in the soil.