Published online by Cambridge University Press: 31 May 2012
A statewide survey was made in Florida to determine the resistance of house flies, Musca domestica L., from 25 different locations throughout the state to trichlorfon and dichlorvos in dry sugar baits. When compared with susceptible flies (Orlando regular strain), the resistance to trichlorfon ranged from 2.5- to 135.0-fold in flies from dairies and from 5.0- to 310.0-fold in flies from poultries. The resistance level to dichlorvos was 1.0- to 22.5-fold in those fly strains collected in dairies and 2.3- to 16.6-fold in those collected in poultry houses.