Genomic diversity of chickpea-nodulating rhizobia in Ningxia (north central China) and gene flow within symbiotic Mesorhizobium muleiense populations.

Genomic diversity of chickpea-nodulating rhizobia in Ningxia (north central China) and gene flow within symbiotic Mesorhizobium muleiense populations. Syst Appl Microbiol. 2020 Jul;43(4):126089 Authors: Zhang J, Peng S, Shang Y, Brunel B, Li S, Zhao Y, Liu Y, Chen W, Wang E, Singh RP, James EK Abstract Diversity and taxonomic affiliation of chickpea rhizobia were investigated from Ningxia in north central China and their genomic relationships were compared with those from northwestern adjacent regions (Gansu and Xinjiang). Rhizobia were isolated from root-nodules after trapping by chickpea grown in soils from a single site of Ningxia and typed by IGS PCR-RFLP. Representative strains were phylogenetically analyzed on the basis of the 16S rRNA, housekeeping (atpD, recA and glnII) and symbiosis (nodC and nifH) genes. Genetic differentiation and gene flow were estimated among the chickpea microsymbionts from Ningxia, Gansu and Xinjiang. Fifty chickpea rhizobial isolates were obtained and identified as Mesorhizobium muleiense. Their symbiosis genes nodC and nifH were highly similar (98.4 to 100%) to those of other chickpea microsymbionts, except for one representative strain (NG24) that showed low nifH similarities with all the defined Mesorhizobium species. The rhizobial population from Ningxia was genetically similar to that from Gansu, but different from that in Xinjiang as shown by high chromosomal gene flow/low differentiation with t...
Source: Systematic and Applied Microbiology - Category: Microbiology Authors: Tags: Syst Appl Microbiol Source Type: research