European Journal of Entomology

      ISSN 1210-5759 (print), 1802-8829 (online)

Eur. J. Entomol. 2010, 107(3): 299–304  

The effect of host plant and isolation on the genetic structure of phytophagous insects: A preliminary study on a bruchid beetle

RESTOUX G., HOSSAERT-MCKEY M., BENREY B. & ALVAREZ N.*

Genetic differentiation is a consequence of the combination of drift and restriction in gene flow between populations due to barriers to dispersal, or selection against individuals resulting from inter-population matings. In phytophagous insects, local adaptation to different kinds of host plants can sometimes lead to reproductive isolation and thus to genetic structuring, or even to speciation. Acanthoscelides obtectus Say is a bean bruchid specialized on beans of the Phaseolus vulgaris group, attacking both wild and domesticated forms of P. vulgaris and P. coccineus. This study reveals that the genetic structure of populations of this bruchid is explained mainly by their geographical location and is not related to a particular kind (wild or domesticated) of bean. In contrast, the species of bean might have led, to some extent, to genetic structuring in these bruchids, although our sampling is too limited to address such process unambiguously. If confirmed, it would corroborate preliminary results found for the parasitoid species that attack Acanthoscelides species, which might show a genetic structure depending on the species of host plant.

Address
University Neuchâtel, 11 E.-Argand, CH-2007 Neuchâtel, Switzerland; e-mail: nadir.alvarez@unil.ch

Keywords
Phytophagous insects, Bruchidae, Acanthoscelides, spatial genetic structure, gene flow, adaptation

accepted: Mar 29th, 2010    published: Jul 20th, 2010    URL: http://www.eje.cz/scripts/viewabstract.php?abstract=1540


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