This study presents a phylogenetic analysis of the selected representatives of the Triticeae tribe and the assessment of possibilities of species identification on the basis of sequence variation in the three regions from the chloroplast DNA (matK, rbcL and trnH-psbA). The analysis included diploid and polyploid species of the following genomic compositions: E b , E e , H, I, Ns, St, Ta, Xu, NsXm, XoXr, XuXu, E b E e , E b E b E e , E b E e St, StH, StStH. The obtained matK and rbcL sequences revealed three well-supported clades: (1) Elymus, Lopophyrum, Pseudoroegneria, Thinopyrum (genomes E b , E e , St, StH, E b E e , E b E b E e , E b E e St, StStH); (2) Leymus, Hordelymus, Psathyrostachys (genomes Ns, NsXm, XoXr); (3) Hordeum (genomes H, I, Xu). This results support the view that the analyzed Elymus species (E. caninus, E. repens) acquired the Pseudoroegneria St genome maternally. They also indicate that Hordelymus europaeus carries the Ns genome from Psathyrostachys and point at the maternal origin of this component. Moreover, the presented results confirm the contribution of Psathyrostachys in the origin of Leymus as well as indicate the maternal character of this input. Differentiation observed within the Hordeum clade aligns with the alleged genome composition of the analyzed species. The DNA barcoding potential of the analyzed sequences was low. Nevertheless, several informative polymorphisms were found like e.g. the matK substitution specific for Thinopyrum bessarabicum, the trnH-psbA substitution differentiating Leymus arenarius from Psathyrostachys juncea and the group of speciesspecific deletions within trnH-psbA. In the DNA barcoding context we have also demonstrated negative importance of the high frequency cpDNA inversion leading to intraspecific variation.

To determine the relative importance of clonal growth and sexual reproduction, the Randomly Amplified Polymorphic DNA (RAPD) method was used to study genetic diversity and clonal structure of six populations of Elymus repens and four populations of Elymus hispidus from Poland. These outbreeding species are virtually self-sterile and form widely spreading and long-lived rhizomes. Using 12 primers, a total of 150 unambiguous RAPD fragments were amplified and scored. Results of AMOVA showed no significant genetic distinction between morphologically distinguished varieties of E. repens and E. hispidus. E. repens had slightly higher intra-specific genetic polymorphism than E. hispidus; the percentage of polymorphic bands per population ranged from 38 to 49 and from 19 to 38 respectively. Clonal diversity measured using the Simpson diversity index (D) indicated different contributions of clonal reproduction in particular populations of E. repens (D: 0.20-0.72). Populations of E. hispidus were dominated by one or a few clones, which were generally restricted to a single population (D: 0.00-0.22). RAPD revealed that most genetic diversity resided within populations of the two studied species, suggesting that, despite their clonal character, propagation by seeds contributes considerably to reproduction of E. repens and E. hispidus.

No abstract