Reproductive compatibility of Sorbocotoneaster with mountain ash species and varieties that are promising for breeding in Siberia

In Russia, in the Republic of Yakutia, there is the only point in the world where natural intergeneric hybridization of species of the genera Sorbus and Cotoneaster is observed, resulting in the formation of a new hybridogenic genus ×Sorbocotoneaster with a rich polymorphism of parental genera traits. For the selection of mountain ash in Siberia, it is promising to involve Sorbocotoneaster genotypes in artificial hybridization as sources of a complex of economically valuable traits, including winter hardiness, short stature, and self-fertility. Artificial hybridization of the tetraploid selective form Sorbocotoneaster with selected forms and varieties of Sorbus sibirica, S. aucuparia, S. sambucifolia and their hybrids allows obtaining viable hybrid offspring in combinations where Sorbocotoneaster is used as a pollen donor.