ECOLOGY, SAMPLING, AND MODELING OF INSECT PESTS OF STORED GRAIN, PROCESSING FACILITIES, AND WAREHOUSES
Location: Stored Product Insect Research Unit
Title: Genetic structure of Tribolium castaneum populations in mills
| Semeao, Altair - |
| Beeman, Richard |
| Whitworth, Robert - |
| Sloderbeck, Phillip - |
| Lorenzen, Marce - |
Submitted to: Stored Products Protection International Working Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: February 19, 2010
Publication Date: December 9, 2010
Citation: Semeao, A.A., Campbell, J.F., Beeman, R.W., Whitworth, R.J., Sloderbeck, P.E., Lorenzen, M.D. 2010. Genetic structure of Tribolium castaneum populations in mills. In: Stored Products Protection International Working Conference Proceedings, June 27 - July 2, 2010, Estoril, Portugal. p. 85-89.
We investigated the genetic diversity and differentiation among nine populations of T. castaneum using eight polymorphic loci, including microsatellites and other insertion-deletion polymorphisms (=”indels”). Samples were collected in food processing/storage facilities located in Kansas, Nebraska, California, Louisiana, Florida and Puerto Rico. Standard population genetic analysis was applied, and an assignment test was used to assign individuals to their genetic population. All loci were polymorphic across populations, with the number of alleles per locus-population combination varying from 3 to 14. Among 72 locus-by-population combinations, 31 deviated significantly from Hardy-Weinberg equilibrium, which was associated with a deficiency in heterozygosity. T. castaneum populations show some level of genetic structuring. Genetic differentiation between populations, using FST estimates, was significant, with FST varying from 0.018 to 0.149. AMOVA indicated that 8.32% of the variation in allele frequency resulted from comparisons among populations. Genetic distance was not significantly correlated with geographic distance. Correct assignment to the genetic population was possible in only 56% of all individuals. Together, these results revealed that geographically distinct populations of T. castaneum had low to moderate levels of genetic differentiation that was not correlated with geographic distance, and the genotypic profile of the individuals did not provide enough information for fingerprinting them with their source population.