UNIDEF   23986
UNIDAD DE INVESTIGACION Y DESARROLLO ESTRATEGICO PARA LA DEFENSA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
A new type of synergism by behavior modification in blood-sucking bugs simultaneously exposed to eugenol and azamethiphos
Autor/es:
REYNOSO, MERCEDES M.N.; ZERBA, EDUARDO N.; ALZOGARAY, RAÚL A.; SECCACINI, EMILIA A.
Lugar:
Foz Iguazú
Reunión:
Congreso; 1º Join meeting ISCE/ALAER; 2016
Resumen:
Triatoma infestans is the main vector of Chagas disease in Argentina and other Latin American countries. Due to the emergence of resistance to pyrethroid insecticides, it is necessary to develop innovative tools for controlling the insect. For this reason, theobjective of the present study was to evaluate a possible synergism of eugenol on the toxicity of the organophosphate azamethiphos. Eugenol is a botanical monoterpene that produces hyperkinesis in T. infestans. With this background in mind, we hypothesize that an insect exposed to a surface treated with eugenol and azamethiphos would suffer greater toxicity than if it were exposed to azametiphos alone. The cause of this synergism would be an increase in exposure to the organophosphate caused by the increase in the locomotor activity.First instar nymphs of T. infestans were used in all experiments. Ethovision (XT10) software was used to quantify locomotor activity of insects exposed to filter papers impregnated with azamethiphos (25, 50 and 100 µg/cm²) or eugenol (49, 97, 195 and 390 µg/cm²). Hyperkinesis was observed only in insect exposed to 195 or 390 µg/cm². In another experimental series, insects were exposed with azamethiphos alone (12, 50 or 200 µg/cm²), or mixed with eugenol (400 µg/cm²). Values of Lethal Concentration ​​50% (LC50) were 53 µg/cm² for azamethiphosalone, and 6.4 µg/cm² to the mixture. This result supports the hypothesis that hyperkinetic insects incorporate more azamethiphos than those with a normal locomotor activity. We will continue exploring this synergism to assess their potential application in controlling T. infestans.