Phylogenetic relationships and Y genome origin in Chinese Elymus (Triticeae: Poaceae) based on single copy gene DMC1

To investigate the phylogenetic relationships among Chinese Elymus and related diploid genera, the genome donor of Elymus, and the evolutionary history of polyploid Elymus species, disrupted meiotic cDNA1 (DMC1) sequences were analyzed for 10 Elymus species, together with 34 diploid taxa from 13 monogenomic genera. The phylogenetic analyses (Neighbor-Joining) supported three major clades (St, Y and H). Sequence diversity and genealogical analysis suggested that (1) Elymus species are unambiguously closely related to Pseudoroegeria and Hordeum. Pseudoroegeria and Hordeum might be serve as the St genome and H genome donor of polyploid Elymus species; (2) Phylogenetic analyses separated the Y sequences from the St sequences, it confirmed that St and Y genome in Elymus species have originated from different donors; (3) the St genome of Elymus had several origins and diverse species of Pseudoroegneria might have taken part in the formation of polyploid species of Elymus; (4) the DMC1 sequences of Elymus are evolutionarily distinct, and it can clarify parental lineages and phylogenetic relationships of genera Elymus.