Phylogenetically diverse Bradyrhizobium genospecies nodulate Bambara groundnut (Vigna subterranea L. Verdc) and soybean (Glycine max L. Merril) in the northern savanna zones of Ghana
No Thumbnail Available
Files
Date
2022
Journal Title
Journal ISSN
Volume Title
Publisher
FEMS Microbiology Ecology
Abstract
A total of 102 bacterial strains isolated from nodules of three Bambara groundnut and one soybean cultivars grown in nineteen
soil samples collected from northern Ghana were characterized using multilocus gene sequence analysis. Based on a concatenated
sequence analysis (glnII-rpoB-recA-gyrB-atpD-dnaK), 54 representative strains were distributed in 12 distinct lineages, many of which
were placed mainly in the Bradyrhizobium japonicum and Bradyrhizobium elkanii supergroups. Twenty-four of the 54 representative
strains belonged to seven putative novel species, while 30 were conspecific with four recognized Bradyrhizobium species. The nodA
phylogeny placed all the representative strains in the cosmopolitan nodA clade III. The strains were further separated in seven nodA
subclusters with reference strains mainly of African origin. The nifH phylogeny was somewhat congruent with the nodA phylogeny, but
both symbiotic genes were mostly incongruent with the core housekeeping gene phylogeny indicating that the strains acquired their
symbiotic genes horizontally from distantly related Bradyrhizobium species. Using redundancy analysis, the distribution of genospecies
was found to be influenced by the edaphic factors of the respective sampling sites. In general, these results mainly underscore the high
genetic diversity of Bambara groundnut-nodulating bradyrhizobia in Ghanaian soils and suggest a possible vast resource of adapted
inoculant strains.
Description
This article is published by FEMS Microbiology Ecology, 2022 and is also available at DOI: 10.1093/femsec/fiac043
Keywords
Citation
FEMS Microbiology Ecology, 2022, 98, 1–17