Funded by Genome Canada, the Government of Alberta through Genome Alberta, and Genome British Columbia in support of the Tria I and Tria II projects.
Phylogeographic insights into an irruptive pest outbreak
Article first published online: 8 APR 2012
© 2011 The Authors. MicrobiologyOpen published by Blackwell Publishing Ltd.
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
Ecology and Evolution
Volume 2, Issue 5, pages 908–919, May 2012
How to Cite
Cullingham, C. I., Roe, A. D., Sperling, F. A. H. and Coltman, D. W. (2012), Phylogeographic insights into an irruptive pest outbreak. Ecology and Evolution, 2: 908–919. doi: 10.1002/ece3.102
Ecology and Evolution 2012; 2(5): 908–919
- Issue published online: 10 MAY 2012
- Article first published online: 8 APR 2012
- Received: 6 December 2011; Accepted: 7 December 2011
- Dendroctonus ponderosae;
- irruptive populations;
- mountain pine beetle;
Irruptive forest insect pests cause considerable ecological and economic damage, and their outbreaks have been increasing in frequency and severity. We use a phylogeographic approach to understand the location and progression of an outbreak by the MPB (Dendroctonus ponderosae Hopkins), an irruptive bark beetle that has caused unprecedented damage to lodgepole pine forests in western North America and is poised to expand its range across the boreal forest. We sampled MPB populations across British Columbia and Alberta and used phylogeographic methods to describe lineage diversification, characterize population structure, investigate expansion dynamics, and identify source populations of the outbreak. Using 1181 bp of mitochondrial DNA sequence from 267 individuals, we found high haplotype diversity, low nucleotide diversity, and limited lineage diversification. The overall pattern was consistent with isolation by distance at a continental scale, and with reduced diversity and population structure in the northerly, outbreak regions. Post-Pleistocene expansion was detected, however more recent expansion signals were not detected, potentially due to the size and rapid rate of range expansion. Based on the limited genetic structure, there were likely multiple source populations in southern British Columbia, although the magnitude of the demographic expansion and rate of spread have obscured the signature of these source populations. Our data highlight the need for caution in interpreting phylogeographic results for species with similar demographics.