Location: Southern Insect Management ResearchTitle: Genetic structure and gene flow among Brazilian populations of Heliothis virescens (F.) (Lepidoptera: Noctuidae) Author
Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/18/2012
Publication Date: 12/1/2012
Citation: Domingues, F.A., Silva-Brandao, K.L., Abreu, A.G., Perera, O.P., Blanco, C.A., Consoli, F.L., Omoto, C. 2012. Genetic structure and gene flow among Brazilian populations of Heliothis virescens (F.) (Lepidoptera: Noctuidae). Journal of Economic Entomology. 105(6)2136-46. Interpretive Summary: Tobacco budworm, Heliothis virescens, larvae collected from cotton and soybean plants from 12 localities in Brazil were analyzed with nine microsatellite markers to evaluate gene flow, genetic structure, and genetic diversity. Low levels of gene flow and moderate to high genetic structuring was observed among populations studied. Statistical analyses indicated that there is no correlation between genetic structuring and geographic origin, host plant association, or crop growing season. Other factors, including demographic history and seasonal variability of intra-population genetic variation, appear to be molding the current pattern of genetic variability distribution.
Technical Abstract: Population genetic studies are essential to the better application of pest management strategies, including the monitoring of the evolution of resistance to insecticides and genetically modified plants. Bt-crops have been instrumental in controlling Heliothis virescens (F.), a pest that has developed resistance to many commonly insecticides once used for its management. In our study, microsatellite markers were applied to investigate the genetic structure and patterns of gene flow among Brazilian populations of H. virescens from cotton- and soybean-fields, aiming to propose means to improve its management in the field. A total of 127 alleles were found across nine microsatellites loci for 205 individuals from 12 localities. Low levels of gene flow and moderate to great genetic structure were found for these populations. Host plant association, crop growing season and geographic origin were not responsible for the genetic structuring among Brazilian populations of H. virescens. Other factors, such as demographic history and seasonal variability of intrapopulation genetic variation, were suggested to be molding the current pattern of genetic variability distribution.