LANDSCAPE GENOMICS OFPOPULUS TRICHOCARPA: THE ROLE OF HYBRIDIZATION, LIMITED GENE FLOW, AND NATURAL SELECTION IN SHAPING PATTERNS OF POPULATION STRUCTURE

• DOI: 10.1111/evo.12497
• Publication Date: 2014-07-25T14:51:22Z
• Authors: Armando Geraldes; Nima Farzaneh; Christopher J. Gr...; Athena D. McKown; Robert D. Guy; Shawn D. Mansfield; Carl J. Douglas; Quentin C. B. Cronk
• Keywords: Populus trichocarpa; Population genomics

Populus trichocarpa is an ecologically important tree across western North America. We used a large population sample of 498 accessions over wide geographical area genotyped with 34K SNP array to quantify patterns genetic variation in this species (landscape genomics). present evidence that three processes contribute the observed patterns: (1) introgression from sister P. balsamifera, (2) isolation by distance (IBD), and (3) natural selection. Introgression was detected only at margins species' distribution. IBD significant sampled as whole, but no restricted gene flow core drainages southern British Columbia (BC). identified number FST outliers. Gene Ontology analyses revealed outliers are overrepresented genes involved circadian rhythm response red/far-red light when entire dataset considered, whereas BC heat overrepresented. also strong correlations between geoclimate variables allele frequencies outlier loci provide clues regarding selective pressures acting these loci.