Resistance to Temephos, an organophosphorous insecticide, in Culex pipiens from Tunisia, North-Africa

Hassen Ben Cheikh (1) , Nicole Pasteur (2)

1 Laboratoire de Génétique, Faculté de Médecine de Monastir
2 UMR ISEM - Institut des Sciences de l'Evolution de Montpellier

Resistance to temephos, an organophosphorous insecticide (OP), was found to be low (2-fold) in 2 Culex pipiens populations collected in Sayada (mid-eastern Tunisia). This resistance was synergized by an esterase inhibitor (DEF). Two sets of over-produced esterases (A2-B2 and A4-B4), known to be involved in resistance, were identified in almost 50% of the examined insects. In addition, 3% of insects had an insensitive acetylcholinesterase. After selecting larvae of one of the samples (ES) with temephos for 6 generations, a 9-fold increase in resistance was observed. and all mosquitoes were found to carry esterases A2-B2 and an insensitive acetylcholinesterase. These results must be considered in future mosquito control programs, since 2 of the identified genes can lead to high resistance to several organophosphorous insecticides.

Mots clés: Temephos resistance; esterase overproduction; insensitive acetylcholinesterase; mosquitoes

Domaines: Biodiversité et Ecologie

Hassen Ben Cheikh, Nicole Pasteur. Resistance to Temephos, an organophosphorous insecticide, in Culex pipiens from Tunisia, North-Africa. Journal of the American Mosquito Control Association, 1993, 9 (3), pp.335-337. ⟨halsde-00201340⟩