Status of Haematobia irritans (Diptera: Muscidae) Insecticide Resistance in Northeastern Mexico

摘要: Horn fly, Haematobia irritans (L.), populations in northeastern Mexico were surveyed for resistance to fenvalerate and coumaphos. Compared with a susceptible strain of horn flies, levels among field the pyrethroid, fenvalerate, ranged from 36 199 times at LD50 level, indicating that fly control pyrethroids would be unsatisfactory. Resistance organophosphate compound, coumaphos, was less evident, flies only 1 5 locations showing tolerance might interfere adequate control.