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We performed next-generation sequencing of the 18S rDNA-ITS1-5.8S rDNA region along with traditional Sanger sequencing of rbc L, mat K, ndh F, and ITS1-5.8S rDNA-ITS2 to clarify the hybridization pattern in the subtribe Alopecurinae and in the genus Alopecurus in particular. Our data support the hybrid origin of Alopecurus × brachystylus from hybridization between A. geniculatus (sect. Alopecurium ) and A. pratensis (sect. Alopecurus ). Moreover, in the rDNA of hybrid A. × brachystylus , only A. aequalis -like ribotypes from tetraploid A. geniculatus participated. Surprisingly, we found the traces of introgression of A. arundinaceus -like ribotypes not only in hybrid A. × marssonii ( A. geniculatus × A. arundinaceus ) but in A. aequalis s. str. as well. A high-polyploid group from the section Alopecurus , A . aggr. alpinus has undoubted hybrid origin: e. g., A. brachystachyus has rDNA from the sect. Alopecurium . Alopecurus alpinus , with its allies, is clearly distinct from other members of the sect. Alopecurus (especially by maternal line) and thus we can re-establish a previous opinion about the separate group to which A. alpinus belongs. Species from the section Colobachne (presumably Alpine grasses from Ancient Mediterranean region) probably hybridized with the A. alpinus group. Even A. myosuroides (sect. Pseudophalaris ) that could be referred to the separate genus has ribotypes common with the species of the section Alopecurium ( A. aequalis , A. geniculatus ) in one of the accessions. Additionally, we found that the possible polyphyletic origin of the genus Limnas . Limnas stelleri is very close to Alopecurus magellanicus according to NGS data, while L. malyschevii is more or less distinct from other studied species of the genus Alopecurus .

In our article, we analyzed new data on the origin of the hybrid genus × Trisetokoeleria . According to the morphological criteria × T. jurtzevii is a hybrid between Koeleria asiatica s. l. and Trisetum spicatum , × T. taimyrica , and originated from Koeleria asiatica s. l. and Trisetum subalpestre , × T. gorodkowii , a hybrid between Koeleria asiatica and Trisetum ruprechtianum . Later × T. taimyrica was transferred to Koeleria . Parental taxa are prone to active hybridization themselves, thus, new methods of next-generation sequencing (NGS) were needed to clarify the relationships of these genera. For NGS we used the fragment 18S rDNA (part)-ITS1-5.8S rDNA (totally 441 accessions). We analyzed ITS1-5.8S rDNA-ITS2 region, trn L- trn F and trn K- rps 16 from eight samples of the five species, using the Sanger method: × Trisetokoeleria jurtzevii , × T. taimyrica , Koeleria asiatica , Sibirotrisetum sibiricum (= Trisetum sibiricum ), and Trisetum spicatum . We also studied the pollen fertility of × Trisetokoeleria and its possible progenitors. Our data partly contradicted previous assumptions, based on morphological grounds, and showed us a picture of developed introgression within and between Koeleria and Trisetum . × T. jurtzevii , a totally sterile hybrid formed rather recently. We can suppose that × T. jurtzevii is a hybrid between K. asiatica and some Trisetum s. str. Species, but not T. spicatum . × T. gorodkowii , a hybrid in the stage of primary stabilization; it has one unique ribotype related to T. spicatum s. l. The second parental species is unrelated to Trisetum ruprechtianum . × T. taimyrica and is a stabilized hybrid species; it shares major ribotypes with the T. spicatum / T. wrangelense group and has a minor fraction of rDNA related to genus Deyeuxia s. l.