A total of 215 rhizobial strains were isolated and analyzed with 16S rRNA gene, 16S-23S intergenic spacer, housekeeping genes atpD, recA, and glnII, and symbiotic genes nifH and nodC to understand the genetic diversity of @entity1460 rhizobia in Hebei province, China. All the strains except one were symbiotic bacteria classified into nine genospecies in the genera of @entity19062 and @entity34923 . Surveys on the distribution of these rhizobia in different regions showed that @entity19062 and @entity19062 elkanii strains were found only in neutral to slightly alkaline soils whereas @entity19062 yuanmingense, @entity19062 liaoningense-related strains and strains of five @entity34923 genospecies were found in alkaline-saline soils. Correspondence and canonical correspondence analyses on the relationship of rhizobial distribution and their soil characteristics reveal that high soil pH, electrical conductivity, and @entity972 content favor distribution of the B. yuanmingense and the five @entity34923 species but inhibit @entity19063 and B. elkanii. High contents of available @entity3151 and organic matters benefit @entity34923 and B. liaoningense-related strains and inhibit the others groups mentioned above. The symbiotic gene (nifH and nodC) lineages among B. elkanii, @entity19063 , B. yuanmingense, and @entity34923 spp. were observed in the strains, signifying that vertical gene transfer was the main mechanism to maintain these genes in the @entity1460 rhizobia. However, lateral transfer of symbiotic genes commonly in @entity34923 spp. and rarely in @entity19062 spp. was also detected. These results showed the genetic diversity, the biogeography, and the soil determinant factors of @entity1460 rhizobia in Hebei province of China.

Diversity and biogeography of rhizobia isolated from root nodules of XXXX grown in Hebei Province, China.

@entity19063 :: ('373177', 'Species') :: ['B. japonicum'] @entity34923 :: ('380', 'Species') :: ['Sinorhizobium fredii', 'Sinorhizobium'] @entity1460 :: ('3847', 'Species') :: ['soybean'] @entity972 :: ('MESH:D011188', 'Chemical') :: ['potassium'] @entity3151 :: ('MESH:D010758', 'Chemical') :: ['phosphorus'] @entity19062 :: ('375', 'Species') :: ['Bradyrhizobium', 'Bradyrhizobium japonicum']
@entity1460 :: (3847,Species) :: ['Glycine max']
