Does the geographic distance affect the genetic differentiation among bilberry populations sampled in Bosnia and Herzegovina?

Isolation-by-distance (IBD) pattern among bilberry (Vaccinium myrtillus L.) populations has previously been reported for this species in northern Europe. However, the number of molecular studies conducted on bilberry, using everything from isoenzymes, RAPDs to microsatellite markers, are very few and far between. Considering that Bosnia and Herzegovina (B&H) is a country rich with diverse fruit genetic resources, conducting a genetic characterization of the naturally occurring V. myrtillus populations could yield valuable data for the conservation and utilization of this resource. This study entailed genotyping samples collected from three bilberry populations located in Fojnica, Kladanj, and Srebrenica municipalities using seven polymorphic microsatellite or SSR (simple sequence repeats) markers. The obtained molecular data was used to calculate the correlation between the physical distance of the individual B&H populations and a parameter of the genetic differentiation (pairwise Fst). The results of the correlation analyses revealed an absence of a significant isolation-by-distance pattern among the three examined B&H bilberry populations. In addition, the most pronounced genetic differentiation was detected between the Srebrenica and each of the two remaining B&H populations. At the same time, the values for pFst were significant, albeit much lower, between the Fojnica and Kladanj populations. Bilberries from the sampled Srebrenica population appear to be distinct from the other B&H populations, possibly due to the different genetic origin of this population.