Origin of polyploid species in Hordeum (Triticeae; Poaceae)

The genus Hordeum (Triticeae) is classified into 33 species (45 taxa intotal, including subspecies and cytotypes) in the wheat tribe (Poaceae;Triticeae). Phylogenetic relationship, and evolutionary history oftwenty-two diploid and polyploid Hordeum species based on two single–copy nuclear ACC1 and ACC2 genes were investigated usingmaximum parsimony and Bayesian inference. Molecular phylogeneticanalysis demonstrated genetic relationships among taxa and origin ofpolyploids. Our data indicated that H. brachyantherum subsp.brachyantherum might be one tetraploid genome donor of H. lechleri.The Acc1 and Acc2 gene data supported alloploid origin of H. capense,with Eurasian H. marinum subsp. gussoneanum and diploid Asian H.roshevitzii. The findings of the present study suggest additionalcomplexity in the genus Hordeum.

Keywords:

Hordeum , Plastid acetyl-CoA carboxylase , Phylogenetic analysis , Triticeae