Four species of genus Elymus which share common genomes were studied in order to assess their systematic relationships. The isoenzyme variation of six markers was analyzed by polyacrylamide gel electrophoresis (PAGE) in natural populations. Neighbour-joining analysis of isoenzymatic data, based on the pairwise Nei and Li’s genetic similarities showed that E. pycnanthus (genomic formula StEP) is the most distant within the studied species of Elymus . Four species-specific alelles of GOT 1, GOT 3, MDH 2 and IDH 2 were found in E. repens . Two alelles of MDH 2 and GDH were unique for E. pycnanthus . E. elongatus (Ee) and E. hispidus (StEeEb) proved to be the most closely related species. E. repens (StStH) clustered at 0.75 level of similarity with E. elongatus and E. hispidus . The study showed that the species of Elymus possessing common genomes St and E in different combinations are closely related genetic entities. The systematic relationships of these species correspond to their genome constitution. The obtained results supported the taxonomic treatment of Elymus sensu lato as a heterogenous genus that originated by allopolyploidization and reticulate evolution.
Key words: Elymus , isoenzymes, genetic diversity, systematic affinities, genomic constitution
Topic: BIOLOGY