Year: 2015
Type: dissertation
Abstract: Polyploids are often exceptionally evolutionarily successful, and increased adaptive potential may contribute to their prevalence. However, adaptation is not well characterized in polyploids, and the extent that it contributes to polyploid success is currently unclear. Here we investigate the genomic basis of adaptation in one of the world’s most successful weeds. We obtained genotype-by sequencing (GBS) sequences from 261 C. bursa-pastoris accessions and 24 whole genome sequences spanning Eurasia. We identified climate associations and found adaptive signatures consistent with contemporary adaptation in recently colonized Asia, and longer adaptive divergence in the ancestral European range. Signatures of adaptation through selective sweep scans suggest preadapted parental genomes may also contribute to local adaptation in similar habitats. However, native climate did not predict fitness in a common garden. Local environmental adaptation is then likely a subtle factor in C. bursa-pastoris’ success, although the features of its diploid progenitor genomes notably influenced its adaptation.
Source: TSpace (University of Toronto)
Author: Adriana Salcedo
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: green
Funder: University of Toronto
OpenAlex ID: W2592681914