Genetic Structure of Tribolium castaneum (Coleoptera: Tenebrionidae) Populations in Mills

Altair A. Semeao, James F. Campbell, Richard W. Beeman, Marcé D. Lorenzen, R. Jeff Whitworth, Phillip E. Sloderbeck
2012 Environmental Entomology  
The red ßour beetle, Tribolium castaneum (Herbst), is primarily found associated with human structures such as wheat and rice mills. Such structures are predicted to be spatially isolated resource patches with frequent population bottlenecks that should inßuence their genetic structure. Genetic diversity and differentiation among nine populations of T. castaneum collected from wheat and rice mills (ranging from Ͻ1Ð5,700 km apart) were investigated using eight polymorphic loci (microsatellites
more » ... (microsatellites and other insertionÐdeletion polymorphisms, each with 3Ð14 alleles). Seventy-two locus-by-population combinations were evaluated, of which 31 deviated signiÞcantly from HardyÐWeinberg equilibrium, all because of a deÞciency of heterozygotes. AMOVA analysis indicated signiÞcant differences among populations, with 8.3% of the variation in allele frequency resulting from comparisons among populations, and commodity type and geographic region not signiÞcant factors. Although there were signiÞcant differences in genetic differentiation among populations (F ST values ϭ 0.018 Ð 0.149), genetic distance was not signiÞcantly correlated with geographic distance. Correct assignment to the source population was successful for only 56% of individuals collected. Further analyses conÞrmed the occurrence of recent genetic bottlenecks in Þve out of nine populations. These results provide evidence that populations of T. castaneum collected from mills show spatial genetic structure, but the poor ability to assign individuals to source populations and lack of isolation by distance suggest greater levels of gene ßow than predicted originally. This is KAES contribution number 11-099-J. Mention of trade names or commercial products in this publication is solely for the purpose of providing speciÞc information and does not imply recommendation or endorsement by the
doi:10.1603/en11207 pmid:22525075 fatcat:fhs7c3666rgc5mghmc3bdrpjji