Molecular phylogeny of Bromus pectinatus complex (Poaceae) based on the nrDNA ITS and ETS and plastid matK sequences

Phylogenetic relationships of Bromus pectinatus complex and its intersectional hybrid origin were studied using nrDNA ITS and ETS and, plastid matK datasets. A total of 37 taxa representing three outgroups (Hordeum marinum, Triticum turgidum, Littledalea alaica) and 34 taxa of Bromus species were included in phylogenetic analyses. Phylogenetic interspecies relationships were constructed by Bayesian and likelihood analysis. On the basis of the present study, sects. Genea and Bromus were not monophyletic. The plastid and nuclear ribosomal data indicated incongruency related to sects. Bromus and Genea due to the position of B. gedrosianus and B. pulchellus (B. pectinatus complex) as well B. oxyodon and B. sewerzowii, supporting intersectional hybrid origins for these species. Molecular trees didn’t support the hybrid origin of B. pectinatus complex from B. japonicus because of their placement in separated clades. Plastid data were confirmed relationship between B. sterilis and B. tectorum with B. pectinatus complex.