Origin, Evolution, and Adaptation of Wild Phaseolus vulgaris

Wild Phaseolus vulgaris, the progenitor of common bean, has an extraordinary distribution. Wild populations are distributed discontinuously from northern Mexico to northwest Argentina, over a distance of some 10,000 km from approximately 30 N. Lat. to 30 S. Lat. How did this extended distribution arise and what were the consequences for the adaptation of common bean? How does this information affect conservation and utilization in bean breeding? In this presentation, we will describe our research to genotype a representative sample of wild beans with GBS, characterize the climatic range of their distribution, and establish correlations between sequence variation and climatic distribution. Our results show that this distribution arose from multiple dispersal events from a core area in Mesoamerica involving ancestors that remain to be identified (or may be extinct). Several climate variables significantly distinguished wild populations and several DNA sequence motifs were correlated with these variables. Our findings provide hypotheses for further research into sources of heat and drought tolerance, candidate genes involved in tolerance to these abiotic stresses, and marker-assisted selection for these traits.