Insecticide Resistance in the House Fly: Resistance Spectra and Preliminary Genetics of Resistance in Eight Strains13

Abstract
The resistance spectra of 8 strains of house flies, Musca domestics L., were measured in tests with 13 insecticides. Materials tested included organophosphates, carbamates, chlorinated hydrocarbons, cyclodienes, and a botanical. Some strains were resistant to only a limited number of insecticides; others were resistant to most of those tested. The inheritance of resistance was determined in progenies of crosses between the resistant strains and a susceptible strain possessing visible recessive markers controlled by 2nd and 5th chromosomal genes. Resistance to organophosphates and carbamates was associated primarily with 5th chromosomal semidominant genes. Chlorinated hydrocarbon resistance was associated with 5th chromosomal semidominant genes and with 2nd chromosomal recessive genes. Resistance to cyclodienes was associated with gene (s) on chromosome (s) other than the 2nd or the 5th. Additional resistance genes of undetermined number, location, and significance are almost certainly present in some of the strains studied.