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Planktonic bacteria widely distributed in the aquatic ecosystem, a huge number, has a wealth of genetic diversity and a mechanism to adapt to the complex environment, changes in community composition and structure has an important function in the ecosystem. This thesis is based on culture and does not depend on the culture of Huguangyan collecting water samples, respectively, by the two types of universal inbred culture medium, combined with BOX-PCR banding pattern analysis techniques, as well as by building environmental water samples total 10 DNA library of microorganisms categories clarify a the typical maar lake layer of archaeal diversity and bacterioplankton diversity and its seasonal changes. We select the center point of Huguangyan Lake water layer (the deepest water is one of the sites) as typical of the study area, respectively, in the summer and winter of each collected 1m, 5m and 13m water samples bacterioplankton diversity Analysis. First, the separation of each water layer planktonic bacteria culture through the the R2A medium filter agar medium prepared by the lake, a total of 340 bacteria. For screening of bacterial 16S rRNA gene was amplified by PCR for sequencing analysis of DNA through alkaline lysis method and BOX-PCR reaction and manual banding pattern analysis screening differential bands of strains; The RDP data analysis showed that 340 strains belonging to the Proteobacteria door, Actinobacteria, Firmicutes, the lakes often Bacteroides doors and other types of main categories. Proteobacteria door with other types of bacteria in different seasons, the water layer and medium occupies inconsistent, but generally are in a dominant position, which hold more than 76% of the total number of bacteria. Bacteroides on the results of the analysis, appears only in the winter in the sample, the number of the total number of bacteria. Pure strains of the 16S rRNA gene by BLAST on after the results show that most of the pure lines of the various types of bacterial 16S rRNA homology greater than 90%, in addition to summer water samples in the lake configuration medium separation Shui5-7 , Shui5-12-6 Shui13 kind of Shui13-11 and winter water dS1-1-26 dS5 R2A medium separation summer water samples R13-5, R13-7 and winter water samples the middle dR1- 11, dR1-21, their homology is not greater than 90%, has yet cognitive may represent new taxa. Secondly, in the culture-based approach to study bacterioplankton diversity based on further by not dependent culture, through the 10 categories of universal primers constructed Huguangyan in water archaea, bacteria, actinomycetes, thick-walled 10 of the bacteria, cyanobacteria, floating molds, Bacteroides, α-proteobacteria, β-Proteobacteria, and γ-proteobacteria 16S rRNA gene clone library. This regard reveals that the same characteristics with the pure lines of separation results, For example, compared with the inbred strains isolated structure, of archaea and floating mold basic no separated in the two types of general-purpose medium obtained, and only in the Construction the library; the other hand, clone a new sequence of a considerable part of the corresponding families and genera. Such sequences in a different library of different proportions, and were as follows: 6/30 of the total archaea, representing 8/30 of the bacteria attributable actinomycetes 2/30, 2/30 of the Firmicutes, representing floating mold 23/30, 29/30 Bacteroides, cyanobacteria, 3/30, attributable to the α-proteobacteria, 8/30, 11/31 of the total β-Proteobacteria, accounted for 27/31 of the γ-proteobacteria .
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