Research is exploring the relationship between plant evolutionary history and its impact on the recruitment of diazotrophs and the expression of certain genes in the rhizosphere. Studies suggest that plant roots can influence the communities of free-living diazotrophs in soils, and that crop breeding history may also play a role in shaping the rhizosphere microbiome. The findings imply a complex interaction between plant evolution, microbiome composition, and ecosystem functioning, although the specifics of these relationships are still being investigated.