Formamidines resistance

Sparks, T.C., Leonard, B.R., and Graves, J.B., Formamidine metabolism and pyrethroid interactions in pyrethroid resistant tobacco budworms, 1989 Proceedings of the Beltwide Cotton Production Research Conference, National Cotton Council of America, 1989, p. 330. 

More recently, Chen et al. (2007) found two amino acid substitutions (T8P, L22S) in a putative octopamine receptor in amitraz-resistant cattle ticks. Thus, point mutations may play a role in resistance to formamidine pesticides in ticks. 

The acaricidal activity of these formamidines is based on a mechanism which is entirely different from that of the chlorinated hydrocarbons, organophosphates and carbamates. Some of them are more toxic to organophosphate-resistant mites than to organophosphate susceptible ones (Dittrich, 1969). 

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