%0 Conference Proceedings
%9 ACTI : Communications avec actes dans un congrès international
%A Chandre, Fabrice
%A Darriet, Frédéric
%A Doannio, J.M.C.
%A Pasteur, N.
%A Guillet, Pierre
%T Insecticide resistance, mechanisms and gene flow in Culex quinquefasciatus from West Africa
%S Proceedings of the 2nd international conference on insect pests in the urban environment
%C Exeter
%D 1996
%E Wildey, K.B.
%L fdi:010007010
%G ENG
%I BPC Weatons
%@ 0-952-18241-6
%K ENTOMOLOGIE MEDICALE ; INSECTICIDE CHIMIQUE ; RESISTANCE ; VARIABILITE GENETIQUE ; POLYMORPHISME ENZYMATIQUE
%K COTE D'IVOIRE ; BURKINA FASO
%P 640
%U https://www.documentation.ird.fr/hor/fdi:010007010
%> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/pleins_textes_6/b_fdi_45-46/010007010.pdf
%W Horizon (IRD)
%X Larval susceptibility to organophosphates (OP), carbamates (CARB) and pyrethroids (PYR) was investigated in #Culex quinquefasciatus$ from Côte d'Ivoire and Burkina Faso. A total of 33 populations collected in 25 cities were tested. The resistance of these natural field populations was compared to a susceptible reference strain under the same conditions. In Côte d'Ivoire, populations showed a heterogeneous response to OP and CARB. A range of 40 %-98 % of larvae had a low resistance level to both chlorpyrifos (2-8x) and propoxur (1-4x). The remaining 2 % to 60 % of larvae displayed a high level of cross-resistance between chlorpyrifos (15-30x) and propoxur (>700x). Biochemical studies showed that low level resistance to OP was due to A2-B2 overproduced esterases and that cross-resistance to OP and CARB was conferred by an insensitive acetylcholinesterase (AChE). This AChE provided a lower resistance to temephos (10x). In Burkina Faso, populations were slightly resistant to OP (1-3x) and not to CARB. The esterases A2-B2 were only present at 50 % frequency. In contrast, PYR-resistance was similar between the two countries. All populations were resistant to either permethrin (20-80x) and deltamethrin (15-40x). Bioassays using piperonyl butoxide (PB) and biochemical studies showed that PYR-resistance involved increased metabolism by mixed function oxidases. Knowing that synergism of PB did not completely suppress resistance and that adults did not show a knockdown effect with high permethrin concentrations, it is likely that PYR-resistance was also due to a Kdr gene. (Résumé d'auteur)
%B Insect Pests in the Urban Environment : International Conference
%8 1996/07/07-10
%$ 052CULARB