The structure of Dreissena polymorpha populations from basins adjacent to the Chernobyl atomic power station

Abstract The genetic and morphological differences among seven Dreissena polymorpha populations exposed to various environmental factors in the water basins adjacent to the Chernobyl atomic power station were examined. All of the populations showed differences in gene frequencies at four polymorphic loci. The populations could be divided into two groups according to temperature regime at the breeding site. Differences in Dreissena polymorpha populations were observed largely for those loci that showed significant deviations from the Hardy-Weinberg distribution. Radiation failed to cause any significant effect on the population structure. Within the limits considered, diversity in shell coloration among Dreissena polymorpha populations was governed by conditions at the breeding site (character of the substrate, rate of water flow, etc.), and not by thermal or radioactive contamination.