Evaluation of seven housekeeping genes for multilocus sequence analysis of the genus Mesorhizobium: Resolving the taxonomic affiliation of the Cicer canariense rhizobia.

Cicer canariense is a wild chickpea that can be nodulated by Mesorhizobium strains belonging to nine different genomic groups or genospecies. In this study, multilocus sequence analysis (MLSA) of seven protein-coding genes, recA, glnII, dnaK, rpoB, gyrB, truA and thrA, was used to resolve the phylogenetic relationships and taxonomic affiliation of 27 representative strains from all the genotypes. Individual phylogenies were mostly congruent, although there were a few discrepancies.

Lotus endemic to the Canary Islands are nodulated by diverse and novel rhizobial species and symbiotypes.

Genetic and symbiotic characterization of 34 isolates from several Lotus species endemic to the Canary Islands showed extraordinary diversity, with bacteria belonging to different species of the genera Mesorhizobium (17 isolates), Sinorhizobium (12 isolates) and Rhizobium/Agrobacterium (5 isolates). In a previous report, we showed that the Sinorhizobium isolates mostly belonged to S. meliloti.

Different Mesorhizobium species sharing the same symbiotic genes nodulate the shrub legume Anagyris latifolia.

The isolation and characterization of six rhizobial strains isolated from Anagyris latifolia, a shrub legume endemic to the Canary Islands, is reported in this study. The isolates were characterized by 16S-ARDRA, and sequencing of the ribosomal 16SrRNA gene, the 16S-23SrDNA intergenic spacer region, and the housekeeping gene for glutamine synthetase II (glnII). The phylogenies based on the three types of sequences matched, showing that the isolates belonged to three distinct lineages within the genus Mesorhizobium that could represent different species.

Bradyrhizobium canariense sp. nov., an acid-tolerant endosymbiont that nodulates endemic genistoid legumes (Papilionoideae: Genisteae) from the Canary Islands, along with Bradyrhizobium japonicum bv. genistearum, Bradyrhizobium genospecies alpha and Bradyrhizobium genospecies beta.

Highly diverse Bradyrhizobium strains nodulate genistoid legumes (brooms) in the Canary Islands, Morocco, Spain and the Americas. Phylogenetic analyses of ITS, atpD, glnII and recA sequences revealed that these isolates represent at least four distinct evolutionary lineages within the genus, namely Bradyrhizobium japonicum and three unnamed genospecies. DNA-DNA hybridization experiments confirmed that one of the latter represents a new taxonomic species for which the name Bradyrhizobium canariense is proposed.

Genetic diversity of bradyrhizobial populations from diverse geographic origins that nodulate Lupinus spp. and Ornithopus spp.

The genetic diversity of 45 bradyrhizobial isolates that nodulate several Lupinus and Ornithopus species in different geographic locations was investigated by 16S rDNA PCR-RFLP and sequence analysis, 16S-23S rDNA intergenic spacer (IGS) PCR-RFLP analysis, and ERIC-PCR genomic fingerprinting. Reference strains of Bradyrhizobium japonicum, B. liaoningense and B.