RESUMO
The flight of the lesser grain borer, Rhyzopertha dominica (F.), near grain storages and at distances from them, was investigated to assess the potential of these beetles to infest grain and spread insecticide resistance genes. We caught R. dominica in pheromone-baited flight traps (and blank controls) set at storages, in fields away from storages, and in native vegetation across a 12-mo period. A functional set of highly polymorphic microsatellite markers was developed, enabling population genetic analyses on the trapped beetles. Pheromone-baited traps caught just as many R. dominica adults at least 1 km from grain storages as were caught adjacent to grain storages. Samples of beetles caught were genetically homogeneous across the study area (over 7,000 km2) in South Queensland, Australia. However, a change in genetic structure was detected at one bulk storage site. Subsequent analysis detected a heterozygous excess, which indicated a population bottleneck. Only a few beetles were caught during the winter months of June and July. To assess the mating status and potential fecundity of dispersing R. dominica females, we captured beetles as they left grain storages and quantified offspring production and life span in the laboratory. Nearly all (95%) of these dispersing females had mated and these produced an average of 242 offspring. We demonstrated that R. dominica populations in the study area display a high degree of connectivity and this is a result of the active dispersal of mated individuals of high potential fecundity.
Assuntos
Distribuição Animal , Besouros/fisiologia , Variação Genética , Comportamento Sexual Animal , Animais , Besouros/genética , Feminino , Fertilidade , Controle de Insetos , Masculino , Feromônios/farmacologia , Queensland , Análise Espaço-TemporalRESUMO
A new species is described from Argentina: Eueupithecia vollonoides sp. n. and a differential diagnosis from E. cisplatensis Prout, 1910 is given. The genus Eueupithecia Prout, 1910 (Sterrhinae), so far having been retained to be monotypic, includes two species now.