Open AccessCharacterizing the physical and genetic structure of the lodgepole pine × jack pine hybrid zone: mosaic structure and differential introgression
Author(s) -
Cullingham Catherine I.,
James Patrick M. A.,
Cooke Janice E. K.,
Coltman David W.
Publication year - 2012
Publication title -
evolutionary applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.776
H-Index - 68
ISSN - 1752-4571
DOI - 10.1111/j.1752-4571.2012.00266.x
Subject(s) - introgression , pinus contorta , hybrid zone , hybrid , biology , range (aeronautics) , gene flow , mountain pine beetle , genetic structure , species distribution , ecology , botany , genetic variation , gene , genetics , habitat , materials science , composite material
Understanding the physical and genetic structure of hybrid zones can illuminate factors affecting their formation and stability. In north‐central A lberta, lodgepole pine ( P inus contorta D ougl. ex L oud. var. latifolia ) and jack pine ( P inus banksiana L amb) form a complex and poorly defined hybrid zone. Better knowledge of this zone is relevant, given the recent host expansion of mountain pine beetle into jack pine. We characterized the zone by genotyping 1998 lodgepole, jack pine, and hybrids from B ritish C olumbia, A lberta, S askatchewan, O ntario, and M innesota at 11 microsatellites. Using B ayesian algorithms, we calculated genetic ancestry and used this to model the relationship between species occurrence and environment. In addition, we analyzed the ancestry of hybrids to calculate the genetic contribution of lodgepole and jack pine. Finally, we measured the amount of gene flow between the pure species. We found the distribution of the pine classes is explained by environmental variables, and these distributions differ from classic distribution maps. Hybrid ancestry was biased toward lodgepole pine; however, gene flow between the two species was equal. The results of this study suggest that the hybrid zone is complex and influenced by environmental constraints. As a result of this analysis, range limits should be redefined.