Macro- and microevolution of bacteria in symbiotic systems

Multicomponent symbiosis of legumes with beneficial soil microorganisms: Genetic and evolutionary bases of application in sustainable crop production

“…Thus, it seems, host plants developed similar mechanisms during co evolution with different microorganisms (see review by Provorov, 2009). In turn, BSM developed similar mechanisms of adaptation to existence in a direct contact with different plant tissues, using an older AM development programs (Provorov et al, 2008;Provorov, 2009). Indeed, the microsym bionts of many other plant-microbial symbioses, including nodule bacteria (Sprent, 2001;Balachandar et al, 2007), represent polyphyletic groups, which is consistent with the later emergence of these symbioses during parallel evolution.…”

Simulation of Plant-Bacteria Co-Evolution in the Mutually Beneficial Symbiosis

“…Moreover, legume-rhizobia symbioses had undergo a prolonged evolution towards an improved mutualism efficiency as it is evident from increasing complexity of nodular structure (Sprent, 2007) and from the progressive specialization of the rhizobial nitrogenase system for symbiotic purposes (Provorov et al, 2008). Such evolution is not correlated to transformation of the facultative mutualistic symbioses into obligatory ones which may be blocked by a high cost of vertical transmission (Genkai-Kato and Yamamura, 1999) or by an excessive ecological specialization of host restricting its adaptive amplitude (Douglas, 1998).…”

“…With respect to rhizobia-legume symbiosis, this hypothesis assumes that allocation of plant-derived C-compounds implemented in favor of N 2 -fixing strains leads to inter-deme or kin selection in rhizobia population (Provorov et al, 2008) enhanced by host "sanctions" against non-fixing strains (Denison, 2000). This mechanism may be effective only if the in planta multiplication of rhizobia is essentially clonal (i. e., N 2 -fixing nodules do not contain the strains which are not capable of N 2 fixation).…”

“…These feedbacks can ensure the regular reorganizations in endo-symbiotic microbial populations eliciting the selective pressures responsible for evolution of host-beneficial (mutualistic) traits. For example, allocation of host-derived C compounds in favor of N 2 -fixing strains in combination with the hosts' "sanctions" against non-N 2 -fixing strains (Denison and Kiers, 2004) can ensure the preferential in planta multiplication of N 2 -fixing strains resulted in the group (inter-deme) selection in favor of symbiotic mutualism (Provorov et al, 2008). However, efficiency of this selection may be restricted greatly by the mixed nodule infections due to which many nodules formed under field conditions contain compositions of N 2 -fixing and non-fixing strains.…”

Effectiveness of Soybean Inoculation with Indigenous Symbiotic Culture in the Yenisei Siberia

“…The effect of horizontal gene transfer that takes place both within a species and between species, genera, or families is shown in [7]. This process can lead to the appearance of strains with different plant specificity and unequal nitrogen fixation efficiency [8].…”