Genotypic variability of Sorbus domestica in Central Europe revealed by the SSR markers

The service tree (Sorbus domestica) is a rare tree species with a scarce distribution across Europe. In Central Europe, where it occurs at northern distribution limits, it is confined to several areas with a very scattered distribution affected by the human impact on the landscape. In this study, we aimed to understand the genetic diversity of its Central European population in a fragmented landscape and its relationship to the origin of different populations. We used 5 microsatellite loci to analyse 189 individuals from 13 populations, mainly from Central Europe with additional sampling from other parts of Europe and Asia. Standard population genetic characteristics and investigation on population structure revealed relatively high genetic diversity within populations, suggesting long-distance pollen dispersal and/or dispersion influenced by humans. All populations showed weak to moderate genetic differentiation, revealing that the marginal Central European population forms clusters that are linked to other Pannonian or Mediterranean populations, whereas Bohemian ones are linked to German populations, suggesting different origins for the populations in the eastern vs. western parts of Central Europe. Genetic variation suggests a natural continuum with neighbouring populations; however, relatively high genetic variation, the character of localities and population structure suggest an anthropogenic origin.