Genetic structure of natural and cultured populations of the oyster (Ostrea edulis L.) in the Adriatic Sea

Abstract

       Starch gel electrophoresis was used to determine the genetic structure, as well as population differentiation in and among natural and cultured populations of the European flat oyster (Ostrea edulis, L.) from the eastern coast of the Adriatic Sea.

       From three natural and three cultured populations, seven enzyme loci were analysed: 6- Phosphogluconate dehydrogenase (6Pgd), Isocitrate dehydrogenase (Idh), Glucosephosphate iso­merase (Pgi) and Peptidase (-a, -b, -c, -d).

       None of the populations revealed significant deviations from the expected HARDY-WEINBERG equilibrium frequencies of genotypes, which propose that mating was random within each popula­tion. The number of percent of polymorphic loci per population, mean heterozygosity and effective number allele per locus indicate that the levels of genetic variations O.edulis populations at the eastern coast of the Adriatic Sea are higher in comparison to other oyster populations from the Mediterranean and Atlantic beds.

       There is no heterozygote deficiency within populations, nor differentiations in gene frequencies between natural and cultured populations.