Effectiveness of Methoprene, an Insect Growth Regulator, Against Temephos-Resistant Aedes aegypti Populations from Different Brazilian Localities, Under Laboratory Conditions

Ima Aparecida Braga, Cícero Brasileiro Mello, Isabela Reis Montella, José Bento Pereira Lima, Ademir De Jesus Martins Júnior, Priscila Fernandes Viana Medeiros, Denise Valle
2005 Journal of medical entomology  
The susceptibility of Aedes aegypti (L.) larvae from several Brazilian populations to the juvenile hormone analog methoprene and the organophosphate insecticide temephos were investigated. Populations from Natal (northeastern region), Macapá (northern region), and Jardim Amé rica, Rio de Janeiro (southeastern region) are temephos-resistant (RR 90 ϭ 24.4, 13.3, and 15.8, respectively), whereas populations from Presidente Prudente (southeastern region) and Porto Velho (northern region) exhibit
more » ... region) exhibit only an incipient temephos-altered susceptibility status (RR 90 ϭ 1.8 and 2.6, respectively). Biochemical assays revealed alterations of the enzymes implicated in metabolic resistance, glutathione S-transferase, mixed function oxidases and esterases, among these populations. DoseÐresponse assays showed at most a low resistance to methoprene of all populations tested, irrespective of their temephos resistance level. However, sequential exposure of Macapá and Natal populations to temephos and methoprene indicated a potential cross-resistance when larvae are exposed to both insecticides. Nevertheless, susceptibility of the Brazilian Ae. aegypti populations to methoprene alone suggests this insect growth regulator could substitute for temephos in the control of the dengue vector in the country.
doi:10.1603/0022-2585(2005)042[0830:eomaig]2.0.co;2 pmid:16363168 fatcat:jtxwff3jyndofopsbq5mzbsp4q