Genetic diversity structure of Salix Caprea L. populations from fragmented riparian habitats

Abstract

Abstract Goat willow (Salix caprea L.) is an ecologically important, cold-tolerant pioneer species that spread from central Anatolia to the Black Sea regions in Türkiye. Completed and ongoing construction of hydroelectric plants, especially in northeastern Turkey, threaten the genetic resources of goat willow in the region due to habitat loss and fragmentation. Therefore, it is important to asses genetic diversity structure and magnitude of goat willow populations in the northeastern Black Sea Region for effective conservation of genetic resources of the species. To characterize the genetic diversity of Salix caprea, 180 trees were sampled and screened by using ten microsatellite markers for genotyping, consequently analysis were carried out to estimate population genetic diversity parameters of populations. The results revealed that both observed (Ho = 0.50) and expected (He = 0.54) genetic diversities were low, but observed genetic diversity was less than expected due fragmentation and reduction in population sizes. Genetic structure analysis of populations suggested the presence of two major groups. One included the populations of Trabzon provinces and the other had the populations of the Artvin provinces. This structuring appeared to be caused by the restricted gene flow (polen, seed or vegetative material) through wind and water) due to geographical barrier (the east Black Sea mountain ranges) acting as geographic isolation mechanism between the populations of Trabzon and Artvin provinces. To prevent further deteroiation of genetic diversity due to habitat loss and fragmentation in the studied river systems in the region, it is suggested that effective gene conservation and management programs should be developed for the species by using the genetic information from the current study.