Competition between insecticide-susceptible and resistant populations of the maize weevil, Sitophilus zeamais

Insecticide resistance is an evolutionary response to insecticides and, as such, important for environmental biomonitoring and for pest management. Fitness disadvantage in the absence of insecticide is a frequent assumption in models of insecticide resistance evolution, which was observed in differe...

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Detalles Bibliográficos
Autores: Oliveira, Eugênio E., Guedes, Raul Narciso C., Tótola, Marcos R., Marco Jr., Paulo De
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:Brasil
Institución:Universidade Federal de Viçosa (UFV)
Repositorio:LOCUS Repositório Institucional da UFV
Idioma:inglés
OAI Identifier:oai:locus.ufv.br:123456789/19180
Acceso en línea:https://doi.org/10.1016/j.chemosphere.2007.04.077
http://www.locus.ufv.br/handle/123456789/19180
Access Level:acceso abierto
Palabra clave:Adaptative evolution
Coleoptera
Curculionidae
Fitness disadvantage
Physiological costs
Pyrethroid resistance
Descripción
Sumario:Insecticide resistance is an evolutionary response to insecticides and, as such, important for environmental biomonitoring and for pest management. Fitness disadvantage in the absence of insecticide is a frequent assumption in models of insecticide resistance evolution, which was observed in different insect species. Fitness studies are based in demographic performance of isolated populations without direct interaction between insecticide-resistant and -susceptible populations. Here we reported a study of direct competition following a factorial bivariate design between an insecticide-susceptible population of the maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), and one of two insecticide-resistant populations – one exhibiting fitness disadvantage based on demographic studies (Juiz de Fora) and other not exhibiting it (Jacarezinho). Total number of insects, mortality by insecticide, insect body mass and respiration rate were recorded after three generations of competition. Indeed, fitness disadvantage was observed in the resistant population from Juiz de Fora, but not in the population from Jacarezinho, as expected. The higher body mass and respiration rate of the insecticide-resistant insects from Jacarezinho are probably mitigating the physiological costs associated with the insecticide resistance minimizing their fitness disadvantage, what does not take place with the insecticide-resistant insects from Juiz de Fora. These distinct responses between the insecticide-resistant populations are probably related to the length and intensity of field-selection with insecticides.