Líffræðifélag Íslands
Líffræðiráðstefnan 2015
Erindi/veggspjald / Talk/poster E97
Sæmundur Sveinsson (1), Armando Geraldes (2), Quentin Cronk (2)
1. Landbúnaðarháskóli Íslands, 2. University of British Columbia
Kynnir / Presenter: Sæmundur Sveinsson
Tengiliður / Corresponding author: Sæmundur Sveinsson (saemundur@lbhi.is)
The hybrid zone between black cottonwood (Populus trichocarpa Torr. & A.Gray ex Hook.) and balsam poplar (P. balsamifera L.) in northern British Columbia (BC), Canada and Alaska is well known but poorly characterized. Here we used restriction site associated (RAD) markers to examine the geographical structure of this hybrid zone. We examined 23 populations of poplar trees in a latitudinal transect from the Yukon (62 degrees) to southern BC (49 degrees), sequencing 6-8 individuals per population using a reduced representation library to provide a survey of single feature polymorphisms across the genome. The variation takes the form of a stepped cline with a transect contact zone near the Peace River in northern BC. However evidence of hybridity extends for hundreds of kilometers away the contact zone indicating both a partial barrier to hybridization (the step at the contact zone) and extensive genome permeability. The morphological characteristic of carpel number correlates well with genetically determined hybrid index and is highly useful taxonomically. Extensive allelic transfer has occurred between these species through the hybrid zone, making a taxonomically confusing situation. In fact, most trees in northern and interior BC are likely to be genetically admixed to some degree.