The version of microevolutionary relationships between the Siberian species Elymus margaritae, E. komarovii, and E. transbaicalensis (Poaceae) according to sequencing of the nuclear gene GBSS1 (waxy)

Abstract

A comparative study was made of the sequence of the GBSS1 gene fragment in accessions of closely related species Elymus margaritae, E. komarovii, and E. transbaicalensis from Siberia. Nucleotide sequences of the gene were determined for St subgenomes in accessions of E. margaritae and E. komarovii from classical habitats. The StH-genomic constitution was confirmed, and microevolutionary relationships between species were evaluated by constructing the NJ dendrogram. It was shown that variants of the St subgenomes in accessions E. margaritae GUK-1009 and E. komarovii AUK-9803 belong to the North American ancestral line St2 of the genus Pseudoroegneria, in contrast to accessions E. margaritae AUK-0650 and E. komarovii GAR-0501. The latter belong to the Asian branch of St1, together with variants of subgenomes in the species E. gmelinii and E. pendulinus. That is, according to the differentiation levels of the St subgenome, accession E. margaritae GUK-1009 (holotype) is significantly distanted from the accession AUK-0650 (paratype), which in turn is close to accessions of E. komarovii and E. transbaicalensis from East Sayan. According to levels of differentiation of the H subgenome, the studied species did not show noticeable differences.

Population structure and phylogeography of Elymus mutabilis and its genetic relationships with E. transbaicalensis (Poaceae)

“…and E. subfibrosus (Nevski) Czerep. (Agafonov et al 1998, 2005, 2019, Agafonov and Salomon 2002). The latter two have been treated as morphological variants of E. mutabilis (Agafonov and Salomon 2002, Agafonov et al 2005).…”

“…The species are predominately self‐pollinating and thus reproductively isolated, but crossing experiments show a variation in sexual compatibility among populations (biotypes). Offspring is semi‐fertile and the taxa belong to the same introgressive gene pool (Agafonov et al 1998, Agafonov 2004). Based on these findings, Agafonov argued that E. mutabilis and E. transbaicalensis should be considered as distinct species.…”