Capturing genetic variation in crop wild relatives: an evolutionary approach

Crop wild relatives (CWRs) offer novel genetic resources for crop improvement. To assist in the urgent need to collect and conserve CWR germplasm, we advance here the concept of an ‘evolutionary’ approach. Central to this approach is the predictive use of spatial proxies of evolutionary processes (natural selection, gene flow, and genetic drift) to locate and capture genetic variation. As a means to help validate this concept, we screened wild-collected genotypes of woodland strawberry (Fragaria vesca) in a common garden. A quantitative genetics approach was then used to test the ability of two such proxies – mesoclimatic variation (a proxy of natural selection) and landscape isolation and geographic distance between populations (proxies of gene flow potential) – to predict spatial genetic variation in three quantitative traits (plant size, early season flower number, and flower frost tolerance). Our results indicated a significant but variable effect of mesoclimatic conditions in struc...