Synergism between cis-permethrin and benzoil phenyl urea insect growth regulators against Aedes aegypti larvae

VALERIA SFARA; SUSANA LICASTRO; HÉCTOR MASUH; EMILIA SECCACINI; RAÚL ALZOGARAY; EDUARDO ZERBA

JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION

American Mosquito Control Association Inc.

Lugar: New Jersey; Año: 2007 vol. 23 p. 24 - 28

8756-971X

Emulsifiable Concentrate formulations of two IGR benzoyl ureas (Novaluron and Diflubenzuron) and the pyrethroid cis-Permethrin were individually bioassayed against late III or early IV-instar larvae of susceptible Aedes aegypti (L.). The EI50 were 0.038; 0.048 and 0.179 ppb for Novaluron, Diflubenzuron and cis-Permethrin, respectively. We also tested 1:1 (V:V) mixtures of cis-Permethrin and benzoyl ureas were also tested EI50 for Novaluron plus cis-Permethrin and Diflubenzuron plus cis-Permethrin were 0.030 and 0.037 respectively with combination indexes (CI) of 0.49 and 0.56, indicating a synergistic interaction between these insecticides. The percentage of larval mortality produced by 0.5 ppb of the mixtures of cis-Permethrin and each IGR, was compared to the addition of larval mortality produced in separated experiments by 0.25 ppb of each component, after 5, 9 and 13 days of continuous exposure. In all bioassays, the Novaluron plus cis-Permethrin mixture produced a significantly higher larvicidal effect (p<0.05) compared with the individual contribution of each compound. The Diflubenzuron plus cis-Permethrin mixture showed significantly higher larval mortality (p<0.05) compared with the contributive effect of each insecticide after 9 and 13 days of exposure, but there was no significant difference after 5 days of exposure.