Genetic Variability and Structure of The Wild Service Tree (Sorbus torminalis (L.) Crantz) in Poland

Sorbus torminalis is a rare forest tree species in Poland. Allelic and genotypic structures at 25 isozyme gene loci were observed in 20 populations from Poland, situated mainly along a latitudinal gradient. Levels of genetic diversity were high both at the species level (P = 44%, He = 0.435) and within populations (mean P = 40.8%, mean H_e = 0.373). Levels of differentiation among populations were relatively high (F_ST = 0.17) and a noticeable geographic structure of this differentiation was detected. The population in the ‘Brekinia’ reserve had a unique genetic structure of a clonal population and was the most distinct from the other populations.