兰坪铅锌尾矿区豆科根瘤菌遗传多样性ARDRA分析

通过16S rDNA扩增产物限制性片段长度多态性分析(ARDRA),对兰坪铅锌尾矿区豆科植物根瘤菌的遗传多样性进行了研究。采用限制性内切酶Hae Ⅲ、Hind Ⅲ、Hinf Ⅰ和Taq Ⅰ对16S rDNA扩增产物进行了酶切分型,根据ARDRA酶切图谱的不同,进行树状聚类。结果表明:49株根瘤菌在40%的相似水平上按氮含量不同及铅锌含量的采集地不同分别聚为OTU1、OTU2和OTU33个群,说明根瘤菌的遗传多样性及分布与土壤中的氮含量和铅锌含量有关。代表菌株的16S rDNA测序结果分析表明,它们在系统发育树上属于Rhizobium sp.、Sinorhizobium sp.和Bradyrhizobium sp.3个系统发育分支,进一步说明兰坪铅锌尾矿区豆科植物根瘤菌多样性较丰富。

ARDRA analysis of genetic diversity of rhizobia isolated from the nodules of leguminous plants in Lanping lead-zinc mine railings of Yunnan Province, Southwest China

By the methods of 16S rDNA cloning,amplified ribosomal DNA restriction analysis(ARDRA),and sequence homology comparison,this paper studied the genetic diversity of rhizobia isolated from the nodules of leguminous plants in Lanping lead-zinc mining tailings of Yunnan.Sequence analysis revealed that among the 49 positive clones in the 16S rDNA library,3 operational taxonomic units(OTUs) were identified,based on the similarity of 40% ARDRA banding profiles at the sampling sites where the nitrogen,Pb2+,Zn2+ contents were different,suggesting that the genetic diversity and distribution of rhizobia could be related to the soil nitrogen,Pb2+,and Zn2+ contents.Diverse phyla of the representative strains in the 16S rDNA library were belonged to the three phylogenetic branches of Rhizobium sp.,Sinorhizobium sp.,and Bradyrhizobium sp.The results suggested that there was a higher genetic diversity of rhizobia isolated from the nodules of leguminous plants in the Lanping lead-zinc mine tailings of Yunna.