Improving the culturability of soil microorganisms and isolating pure strains are the bases of the study of microbial ecology. Three culturing media were used for time interval counting of soil bacteria. Bacterial universal primers were used to amplify 16S rDNA fragments; PCR products digested by restriction endonucleases Hha I and their fingerprints analyzed for influence of culturing methods on soil microbial diversity and culturability. Results indicate that the number of bacteria grown in media LB, CSEA and WSA was 14.84×10~7, 10.27×10~7 and 6.91×10~7 CFU per gram dry soil, respectively, after 192 h of incubation. The diversity index of soil bacteria was the highest in WSA, while the lowest in LB. Certain similarity was discovered in bacteria community between the three media, i.e. the Jaccard index was 57.69% between LB and CSEA, 53.13% between LB and WSA and 66.67% between CSEA and WSA. Phylogenetic analysis suggests that the dominant bacterial groups in the soil belong to β-Proteobacteria,γ-Proteobacteria and Actinobacteria. The sequence of 16S rDNA of some OTUs was found to have high homology with Burkholderiaceae bacterium, Rhodococcus and Mycobacterium, so it is presumed that the cells of these bacteria can secrete Resuscitation Promoting Factors, which may effectively improve culturability of soil microorganisms.%提高土壤微生物的可培养性,获得纯培养微生物菌株,是微生物生态学研究的基础.采用三种培养基对土壤细菌进行分时段计数,以细菌通用引物扩增细菌16S rDNA片段,用限制性内切酶Hha I酶切PCR产物,对酶切图谱进行分型,研究不同培养方法对土壤细菌多样性和可培养的影响.结果表明,LB、CSEA、WSA培养基192 h后每g干土获得的细菌数量分别为14.84×10~7、10.27×10~7和6.91×10~7 CFU,但微生物多样性指数以WSA为最高,LB多样性指数最低;三种培养基培养的细菌菌群有一定的相似性,LB和CSEA培养基间的Jaccard指数为57.69%,LB和WSA培养基之间为53.13%,而CSEA和WSA培养基的相似性指数达66.67%;16S rDNA测序结果表明,所获得的土壤细菌优势种群在分类方面主要属于γ和β变形杆菌以及放线菌亚门,其中某些OTUs中的16S rDNA序列与Burkholderiaceae bacterium、Rhodococcus和Mycobacterium属具有较高的同源性,推测其细胞能够分泌复苏促进因子,有效地提高土壤细菌的可培养性.
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