Species Delineation and Biogeography of Symbiotic Bacteria Associated with Cultivated and Wild Legumes

Abstract

Here, we review key issues in bacterial population genetics and evolutionary biology pertinent to the controversial topics of bacterial species concepts and bacterial biogeography. We present a summary of our results and working hypotheses on the latter topics, based on our population genetic and molecular phylogenetic analyses of diverse populations of rhizobial microsymbionts associated with cultivated and wild legumes. This contribution describes our current understanding and thoughts on the biogeography and nature of rhizobial species associated with (1) common beans (Phaseolus vulgaris, L.), one of the major grain legume crops worldwide, and (2) with wild genistoid legumes from the Canary Islands, Morocco, and continental Spain.