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对农药污染的工业和农业土样中获得的116株阿特拉津降解菌进行分类鉴定,降解菌通过ERIC-PCR和16S rRNA系统进化树分析发现了12种种系型。其中工业土样中鉴定出隶属于节杆菌属的8种种系型降解菌,具有与金黄节杆菌系统进化群体类似的基因种。从无植物生长的工业重度污染土样中检测到嗜碱假单胞菌和Gulosibacter molinativorax系统进化群体间存在着同一种基因型。农业玉米根际土样只分离到3种种系型,与产脲节杆菌类似的基因型是玉米根际普遍存在并占主导地位的降解菌,另外2种种系型代表着具有环境特异性的两个不同起源的类诺卡氏菌分支。基因分型结果暗示着阿特拉津降解群体的多样性和遗传结构的环境特异性,工业土壤中的污染率是影响降解群体多样性和遗传结构的主要因素。
A total of 116 strains of atrazine-degrading bacteria were obtained from industrial and agricultural soil samples contaminated by pesticides. 12 degrading strains were found by ERIC-PCR and 16S rRNA phylogenetic tree analysis. Among them, 8 germ-line degrading bacteria belonging to the genus Arthrobacter were identified in the industrial soil samples, and the genotypes were similar to those of the evolutionary group of Arthrobacter aureus. The presence of the same genotype between P. alkalophilus and the Gulosibacter molinativorax phylogenetic tree was detected in industrial heavily contaminated soil samples without plant growth. Three rhizospheric soil samples were isolated from agricultural maize. The genotypes similar to that of Arthrobacter ureas were ubiquitous and dominant degraders in maize rhizosphere. The other two germline types represented two Nocardioides of different origins. The results of genotyping suggest the diversity of atrazine degradation population and the environmental specificity of genetic structure. The contamination rate in industrial soils is the main factor affecting the diversity and genetic structure of degradation population.