Barley: Genetic Providence and Genetic Provenance Of a Diverse Crop

Multiple factors converge to contribute to high levels of genetic and phenotypic diversity in barley. The progenitor species is ecotypically and genetically diverse, with a large geographic range and large effective population size. Cultivated barley arose from multiple source populations and became adapted to diverse agronomic conditions across much of Eurasia and North Africa over several millennia of human prehistory. Exploiting this diverse adaptive history for barley improvement is challenging if investigations are limited to approaches based on genotype-phenotype associations. A new generation of approaches for exploring genetic data provide the opportunity to investigate the genetic differentiation and genetic provenance of adaptive allelic variation and associations between SNPs and ecogeographic variables. Both sets of approaches provide new opportunities for associating genetic variation with phenotypic traits of agronomic importance, including disease resistance and climate adaptation. We use 2417 worldwide barley accessions (wild, landraces and cultivars) genotyped with 7,800 SNP markers. We seek to identify the geographic regions that best explain the diversity in domesticated barley and associate genes or genomic regions with diverse environmental conditions.