Identification and characterization of rhizospheric microbial diversity by 16S ribosomal RNA gene sequencing

Revista de microbiologia

Mubeen, Samavia¹  Naveed, Muhammad²  Ahmed, Iftikhar³  khan, SamiUllah⁴ 

[1] National Agricultural Research Centre, Islamabad, Pakistan;Quaid-i-Azam University, Islamabad, Pakistan;The University of Queensland, Australia;The University of Tokyo, Tokyo, Japan

关键词: rhizosphere;    root nodules;    16S rRNA gene sequence;    glucose dehydrogenase;    pyrroloquinolone quinone.;   

DOI  :  10.1590/S1517-83822014000300031

学科分类：农业科学（综合）

来源: Sociedade Brasileira de Microbiologia / Brazilian Society for Microbiology

【 摘 要 】

In the present study, samples of rhizosphere and root nodules were collected from different areas of Pakistan to isolate plant growth promoting rhizobacteria. Identification of bacterial isolates was made by 16S rRNA gene sequence analysis and taxonomical confirmation on EzTaxon Server. The identified bacterial strains were belonged to 5 genera i.e. Ensifer, Bacillus, Pseudomona, Leclercia and Rhizobium. Phylogenetic analysis inferred from 16S rRNA gene sequences showed the evolutionary relationship of bacterial strains with the respective genera. Based on phylogenetic analysis, some candidate novel species were also identified. The bacterial strains were also characterized for morphological, physiological, biochemical tests and glucose dehydrogenase (gdh) gene that involved in the phosphate solublization using cofactor pyrroloquinolone quinone (PQQ). Seven rhizoshperic and 3 root nodulating stains are positive for gdh gene. Furthermore, this study confirms a novel association between microbes and their hosts like field grown crops, leguminous and non-leguminous plants. It was concluded that a diverse group of bacterial population exist in the rhizosphere and root nodules that might be useful in evaluating the mechanisms behind plant microbial interactions and strains QAU-63 and QAU-68 have sequence similarity of 97 and 95% which might be declared as novel after further taxonomic characterization.

【 授权许可】

CC BY-NC