Genetic variability of common barbel, Barbus barbus populations in the Czech Republic

During the years 1991-95, 264 individuals of common barbel, Barbus barbus w ere sampled at 10 localities in Czech and Slovak rivers belonging to two se a basins and analysed electrophoretically to reveal possible protein polymo rphism. The species was found to be polymorphic in the area studied. From t he 40 loci studied, 19 were polymorphic with two to eight alleles in each o f them. The mean number of alleles per locus was found between 1.2 and 1.5; the percentage of polymorphic loci varied between 17.1 and 31.4%. The mean observed heterozygosity H-o was found between 0.021 and 0.099. The genetic differentiation among the populations in the Czech Republic expressed by N ei (1972) or Rogers (1972) genetic similarities was found to be very small (0.945 to 0.996 and 0.902 to 0.975, reap.) and we can suppose that the gene tic differentiation in this region is low. Also, the long-term division of river sections (more than 60 years in the case of the River Dyje) did not l ead to an appreciable differentiation.