Serological characterization of five strains of insecticide-resistant and susceptible house flies.

Abstract

Five strains of insecticide-resistant and susceptible house flies, Musca domestica L., were characterized serologically by means of the agar-gel, double-diffusion technique. Antisera against the antigens of these strains of flies were produced in white rabbits. Differences between resistant and susceptible strains were found. An additional component (an extra precipitation band) was found to be present in the DDT-resistant strain and was not found in a DDT-susceptible (Stauffer) strain. Serological absorption techniques indicated the presence of at least one additional component in the DDT-resistant strain. An enzyme, DDT-dehydrochlorinase, is known to be largely responsible for DDT resistance in house flies, and it is thought that this enzyme might be represented by the extra precipitation band. Two dieldrin-and-lindane-resistant strains and 2 dieldrin-lindane-susceptible strains (Stauffer and Wilson) were also characterized serologically. An additional component was found to be present in the Wilson and probably in the Stauffer (both susceptible) strains that was not found present in either of the resistant strains. Spur formation in identity reactions confirmed these differences. The mechanism (s) for dieldrin-lindane resistance have at the present time not been accurately determined, and the serological differences found between dieldrin-lindane resistant and susceptible strains are of interest, in view of the fact that protein (s) not in common may possibly be associated with insecticide resistance.