Abstracts (first author)
Genetic differentiation of Salmonidae populations in Southern Baltic Sea identified from a SNP genotyping
Sea trout Salmo trutta and salmon Salmo salar belonging to Salmonidae family, have a wide distribution, including the rivers flowing into the Baltic Sea. Sea trout migrate from natal rivers to the sea where they forage until reaching sexual maturity, subsequently returning to their native rivers to spawn. The accessibility of natural spawning grounds has become very limited and most populations have been supported by stocking, resulting in a disrupted biodiversity. Genotyping of two Polish populations of sea trout from Vistula and Pomeranian river Słupia has been performed using an Atlantic salmon derived SNP-array. The average Fst over 39 polymorphic loci was 0.13. Generally, Vistula population was more genetically homogeneous, while the population of Pomeranian river was more diverse. Sixty SNPs were selected for further genetic studies of the Southern Baltic populations. Nine sea trout populations (from Poland, Lithuania, Bornholm, Russia and Estonia) were genotyped with the iPLEX Gold technology (Sequenom). Results indicated that the degree of genetic differentiation among populations, measured for 23 loci was moderate (average Fst=0.09). The high differentiation was observed between Polish river Słupia and Russian river (Fst=0.16). Low diversity was detected between Lithuanian Neman river and Polish Vistula river populations. Genetic structure analysis indicates that individuals from 9 populations were clustered into four groups. Atlantic salmon populations have a hierarchical structure of population differentiation and Baltic salmon forms one effectively isolated evolutionary unit of Atlantic salmon. Five populations of salmon (from Polish river Słupia and hatcheries, from Sweden and from Lithuania) were genotyped using an Atlantic salmon derived SNP-array (Illumina). Preliminary results indicated a close relationship between Polish populations from hatcheries relative to wild one and the distinctness of Swedish population.