Genetic heterogeneity in a cyclical forest pest, the southern pine beetle, Dendroctonus frontalis, is differentiated into east and west groups in the southeastern United States
1Department of Zoology, Southern Illinois University Carbondale, Carbondale IL 62901
2Fisheries and Illinois Aquaculture Center, Southern Illinois University Carbondale, Carbondale IL 62901
3Current address: University of South Florida, Department of Integrative Biology, Tampa FL
Abstract
The southern pine beetle, Dendroctonus frontalis Zimmerman (Coleoptera: Curculionidae) is an economically important pest species throughout the southeastern United States, Arizona, Mexico, and Central America. Previous research identified population structure among widely distant locations, yet failed to detect population structure among national forests in the state of Mississippi. This study uses microsatellite variation throughout the southeastern United States to compare the southern pine beetle’s pattern of population structure to phylogeographic patterns in the region, and to provide information about dispersal. Bayesian clustering identified east and west genetic groups spanning multiple states. The east group had lower heterozygosity, possibly indicating greater habitat fragmentation or a more recent colonization. Significant genetic differentiation (θST = 0.01, p < 0.0001) followed an isolation-by-distance pattern (r = 0.39, p < 0.001) among samples, and a hierarchical AMOVA indicated slightly more differentiation occurred between multi-state groups. The observed population structure matches a previously identified phylogeographic pattern, division of groups along the Appalachian Mountain/Apalachicola River axis. Our results indicate that the species likely occurs as a large, stable metapopulation with considerable gene flow among subpopulations. Also, the relatively low magnitude of genetic differentiation among samples suggests that southern pine beetles may respond similarly to management across their range.
Keywords: Dendroctonus, microsatellites, phylogeographic concordance, southern pine beetle
Correspondence:
a* natalieschrey@hotmail.com,
b aschrey@usf.edu,
c edheist@siu.edu,
d jreeve@zoology.siu.edu, *Corresponding author
Editor: Mariana Wolfner was Editor of this paper.
Received: 14 September 2010 | Accepted: 17 January 2011 | Published: 29 August 2011
Copyright: This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.
ISSN: 1536-2442 | Volume 11, Number 110
Schrey NM, Schrey AW, Heist EJ, Reeve JD. 2011. Genetic heterogeneity in a cyclical forest pest, the southern pine beetle, Dendroctonus frontalis, is differentiated into east and west groups in the southeastern United States. Journal of Insect Science 11:110 available online: insectscience.org/11.110
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