Sensibilité aux Insecticides des Populations de Bemisia tabaci (Gennadius, 1889) Collectées dans Différentes Zones de Production Cotonnière en Côte d’Ivoire

Abstract

In recent years, an outbreak of Bemisia tabaci has been observed in Côte d'Ivoire in cotton crops despite the insecticide treatments. An evaluation of the sensitivity levels of insecticides commonly used for the protection of cotton trees has been undertaken in order to identify the most effective active ingredients against B. tabaci. Whitefly populations were collected in six (6) different localities in the cotton production area (Niakara, Bouaké, Ouangolo, Ferké, Boundiali and Korhogo). They were tested by the leaf dipping method with five (5) insecticides of different chemical families (Organophosphorus, Pyrethroids, Neonicotinoids, Sulfoximines, Spinosynes). LC50s for each insecticide were calculated using the probit-log model and compared using variability in insecticide susceptibility of B. tabaci populations and a significant difference between the levels of insect susceptibility to the insecticides tested. Strains from Korhogo showed the lowest susceptibility to profenofos (LC50=71.51 mg.l -1 ), and strains from Boundiali the lowest susceptibility to acetamiprid (LC50=219.96 mg.l -1 ). Acétamipride was significantly less toxic compared to lambdacyhalothrin and profenofos (F=2.58; P=0.04). Sulfoxaflor (LC50=0.71 mg.l -1 ) and spinosad (LC50=4.02 mg.l -1 ) were the most toxic products. This study, which is the first of its kind in Côte d'Ivoire, represents a database for the management of B. tabaci populations.