Patterns of Evolutionary Trajectories and Domestication History within the Genus Hordeum Assessed by REMAP Markers

The patterns of genetic diversity related to the taxonomy and domestication history of 85 accessions representing the main four species of the genus Hordeum were examined by retrotransposon-microsatellite amplified polymorphism (REMAP) markers based on the retrotransposon BARE-1. A substantial level of genetic polymorphisms at among- and within-species level was observed showing that this retrotransposon family and its adjacent genomic regions has been a target for genome dynamics during the evolution and domestication of barley. The obtained data are consistent with the current taxonomic status within the genus Hordeum. Similar level of genetic diversity was observed between the wild and the domesticated barley accessions suggesting that transposable elements` activity and accumulation may counteract the decrease of genome-wide diversity following domestication. In addition, eco-geographical sub-genome pools of the cultivated barley were identified in support to the theory of multiple origins of domestication within the genus Hordeum. We also provide conclusions about the relationship between accessions of different species and the putative routes of barley domestication. In conclusion, the retrotransposon BARE-1 stands as a reliable and perspective DNA marker for the assessment of the phylogenetic and domestication history in the genus Hordeum and other crop species.