Abstract 5
Pavlíček, T. 1994: Geographic variability and wing plasticity in Sitona sulcifrons (Coleoptera, Curculionidae). Bull. ent. Res. 84: 269-273.
Genetic variability in four polymorphic loci and variation in phenotypic plasticity in relation to the relative size of wings, were compared and contrasted among eight local populations of Sitona sulcifrons Thunberg from the Czech and Slovak republics. The distances between localities from which samples were taken were between 49 and 492 kilometres. The results demonstrated that: 1. The variability between populations was 5.5% and the other 94.5% of the total variability was realized within populations. 2. Significant differences in allozyme frequencies among populations existed when distances were more than 100 km. A similar trend was also found in variability of relative wing size in males among populations when distances were more than 200 km. 3. Overall, a significant deficiency of heterozygotes in relation to Hardy-Weinberg predictions existed from all samples. The results support the idea that, at least in agricultural areas, gene flow in S. sulcifrons does not seem to be strong enough to stabilize one large interbreeding population in distances over 100 kilometres.