Biodiversity Of Culturable Halophilic Archaea Isolated From Tamarix Rhizosphere Soil In Lop Nur Region Of XinJiang, China

The biodiversity is the result of the life evolve over long time, and which is the substantial base for the human being to exist on the earth.However it is now faced with the threatener from the increasing population and economic action.In order to build biology data of Lop Nur and offer the data for the further reseach, biodiversity of cultured microbial resources isolated from extreme plant rhizosphere were investigated, in Lop Nur Region of Xin-Jiang, China.The region of Lop Nur is a arid ecosystem. Tamarix community is the dominant in this area. For the protection and utilize of microbial species and genetic resources within the rhizosphere and non-rhizosphere soil of Tamarix community,the quantity of microorganisms and important functional groups were surveyed in October 2007. The results indicate that in Tamarix community, the total numbers of microorganisms of different species in soil are all small. All species overground and underground are correlative in ecosystem function and clear rhizosphere effect is shown.A totally of one hundred and sixty-six halophilic archea strains, 111 strains from rhizosphere soil and 55 strains from non-rhizosphere soil respectively were isolated using complete medium and their upstream partial 16S rRNA gene sequences were determined,which is 51 rhizosphere isolates and 55 non-rhizosphere isolates, in the basis of their morphology, growth and 69 physiochemical characteristics. Phylogenetic analysis based on 16S rRNA genes of all these strains indicated that the isolates from rhizosphere belong to 11 different species of genera Natrialba,Natronorubrum,Haloterrigena,Natronococcus,Natrinema, and that the isolates from non-rhizosphere belong to 8 different species of genera Haloarcula, Halobiforma, Halorubrum, Haloterrigena, Natrinema, Natronorubrum and Natrialba. Most of the 16S rRNA gene sequences related to the genera Natrialba and Haloterrigena were detected in rhizosphere soil. In contrast, sequences related to the genera Natrinema were obtained from non-rhizosphere soil.In addition, the isolates'diversities were analyzed and compared using different diversity indices, richness indices, evenness indices, and species abundance models. There were certain correlations among these indices, and they indicated that halophilic archaea diversity of rhizosphere is higher than that of non-rhizosphere. The discovery of novel species, in a relatively small number of sites from two representative soil, indicated that there are some special microbial resources in Lop Nur region that should be protected and utilized.In this study, the halophilic archaea diversity of rhizosphere and non-rhizosphere in Lop Nur was determined, some new species were described, and the relationship the between plants and halophilic archaea were explored, which may enlarge the boundary of halophilic archaea diversity and provide halophilic archaea resources for further theoretical and applied researches.