Studying the relationships between major crops and the secondary genepools of related species that are more resistant to climate challenges, Mina-Vargas et al. employ nuclear and chloroplast genetic markers to carry out a comprehensive investigation of the genetic diversity of a year-long staple Guatamalan legume crop.
They find that the common bean, Phaseolus dumosus, which has high levels of stress resistance, is closely related to its wild relatives P. coccineus and P. vulgaris, and arose from recent hybridizations between them. Further to analysing all collected specimens of P. dumosus, the authors conclude that this species seems to have lower genetic diversity than its relatives. They also identify regions where diverse populations with additional germplasm of potential value for introgressing favourable traits into other crops within the P. vulgaris genepool might still remain to be uncovered.
Angela M. Mina-Vargas, Peter C. McKeown, Nicola S. Flanagan, Daniel G. Debouck, Andrzej Kilian, Trevor R. Hodkinson, Charles Spillane, 2016, 'Origin of year-long bean (Phaseolus dumosusMacfady, Fabaceae) from reticulated hybridization events between multiple Phaseolus species', Annals of Botany, vol. 118, no. 5, pp. 957-969 http://dx.doi.org/10.1093/aob/mcw138