title: Genome-wide scans detect adaptation to aridity in a widespread forest tree species.
abstract: Patterns of adaptive variation within plant species are best studied through common garden experiments, but these are costly and time-consuming, especially for trees that have long generation times. We explored whether genome-wide scanning technology combined with outlier marker detection could be used to detect adaptation to climate and provide an alternative to common garden experiments. As a case study, we sampled nine provenances of the widespread forest tree species, Eucalyptus tricarpa, across an aridity gradient in southeastern Australia. Using a Bayesian analysis, we identified a suite of 94 putatively adaptive (outlying) sequence-tagged markers across the genome. Population-level allele frequencies of these outlier markers were strongly correlated with temperature and moisture availability at the site of origin, and with population differences in functional traits measured in two common gardens. Using the output from a canonical analysis of principal coordinates, we devised a metric that provides a holistic measure of genomic adaptation to aridity that could be used to guide assisted migration or genetic augmentation.
authors.affiliation: School of Biological Sciences and National Centre for Future Forest Industries, University of Tasmania, Private Bag 55, Hobart, TAS, 7000, Australia; Faculty of Science, Health, Education and Engineering and Collaborative Research Network, University of the Sunshine Coast, Locked Bag 4, Maroochydore, QLD, 4558, Australia.
authors.forename: Dorothy A
authors.initials: DA
authors.lastname: Steane
authors.forename: Brad M
authors.initials: BM
authors.lastname: Potts
authors.forename: Elizabeth
authors.initials: E
authors.lastname: McLean
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Prober
authors.forename: William D
authors.initials: WD
authors.lastname: Stock
authors.forename: René E
authors.initials: RE
authors.lastname: Vaillancourt
authors.forename: Margaret
authors.initials: M
authors.lastname: Byrne
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D001315:Australia; D001499:Bayes Theorem; D002980:Climate; D018744:DNA, Plant / Q000235:genetics; D005052:Eucalyptus / Q000235:genetics*; D005787:Gene Frequency; D005819:Genetic Markers; D018745:Genome, Plant; D008957:Models, Genetic; D025341:Principal Component Analysis; D014197:Trees / Q000235:genetics
chemical_list: D018744:DNA, Plant; D005819:Genetic Markers
keywords: Eucalyptus; assisted migration; canonical analysis of principal coordinates; climate resilience; genome-wide scan; outlier analysis