Population structure and dynamics of insecticide resistance genes in Culex pipiens populations from Italy



We have studied the distribution of resistance genes in relation to genetic structure and gene flow between field populations of Culex pipiens from Italy. Electrophoretic polymorphism of 12 supposed neutral genes showed that genetic differentiation among samples was low and indirect values of Nm provided high estimates of gene flow. In contrast, we observed a strong differentiation in the distribution of resistance genes, highly correlated with the presence/absence of organophosphate insecticide treatments. These results are discussed in relation to the fitness cost of these genes and pattern of dispersal in C. pipiens.