Impacts of Natural Selection on Evolution of Core and Symbiotically Specialized () Genes in the Polytypic Species .

Nodule bacteria (rhizobia) represent a suitable model to address a range of fundamental genetic problems, including the impacts of natural selection on the evolution of symbiotic microorganisms. Rhizobia possess multipartite genomes in which symbiotically specialized () genes differ from core genes in their natural histories. Diversification of genes is responsible for rhizobia microevolution, which depends on host-induced natural selection.

Dynamic of the Soil Microbiota in Short-Term Crop Rotation.

Crop rotation is one of the oldest and most effective methods of restoring soil fertility, which declines when the same plant is grown repeatedly. One of the reasons for a reduction in fertility is the accumulation of pathogenic and unfavorable microbiota. The modern crop rotation schemes (a set of plant species and their order in the crop rotation) are highly effective but are designed without considering soil microbiota dynamics.

Microevolution, speciation and macroevolution in rhizobia: Genomic mechanisms and selective patterns.

Nodule bacteria (rhizobia), N-fixing symbionts of leguminous plants, represent an excellent model to study the fundamental issues of evolutionary biology, including the tradeoff between microevolution, speciation, and macroevolution, which remains poorly understood for free-living organisms. Taxonomically, rhizobia are extremely diverse: they are represented by nearly a dozen families of α-proteobacteria (Rhizobiales) and by some β-proteobacteria. Their genomes are composed of core parts, including house-keeping genes (), and of accessory parts, including symbiotically specialized () genes.

Rhizobia Isolated from the Relict Legume Represent a Genetically Specific Group within biovar .

Twenty-two rhizobia strains isolated from three distinct populations (North Ossetia, Dagestan, and Armenia) of a relict legume were analysed to determine their position within biovar (). These bacteria are described as symbionts of four plant genera , , , and from the Fabeae tribe, of which Vavilovia is considered to be closest to its last common ancestor (LCA). In contrast to biovar , bacteria from biovar () inoculate plants from the Trifolieae tribe.

Microvirga ossetica sp. nov., a species of rhizobia isolated from root nodules of the legume species Vicia alpestris Steven.

Gram-stain-negative strains V5/3MT, V5/5K, V5/5M and V5/13 were isolated from root nodules of Vicia alpestris plants growing in the North Ossetia region (Caucasus). Sequencing of the partial 16S rRNA gene (rrs) and four housekeeping genes (dnaK, gyrB, recA and rpoB) showed that the isolates from V. alpestris were most closely related to the species Microvirga zambiensis (order Rhizobiales, family Methylobacteriaceae) which was described for the single isolate from root nodule of Listia angolensis growing in Zambia.