Cuticular lipids of two resistant and a susceptible strain of houseflies

Abstract

AbstractA study was made of the composition of the cuticular lipids of two resistant strains of houseflies (Rutgers and Fc), both of which show a reduced rate of absorption of insecticides as a partial mechanism of resistance and a susceptible strain (CSMA). Total lipids, monoglycerides, diglycerides and sterol esters (except in the Fc strain), sterols, fatty acids and phospholipid phosphorus were higher in resistant strains than in the susceptible strain. Phosphatidyl‐ethanolamine and phosphatidyl‐choline were major constituents of the phospholipid fractions and were appreciably higher in the resistant strains. Cuticular wax contents did not differ among strains. Incorporation of lipid precursors, [U‐14]acetate and [32P]orthophosphate, was greater in the cuticle of one or both resistant strains, depending on the lipid component examined.