ABSTRACT Forest trees are dominant components of terrestrial ecosystems that have global ecological and economic importance. Despite distributions that span wide environmental gradients,

many tree populations are locally adapted, and mechanisms underlying this adaptation are poorly understood. Here we use a combination of whole-genome selection scans and association analyses

of 544 _Populus trichocarpa_ trees to reveal genomic bases of adaptive variation across a wide latitudinal range. Three hundred ninety-seven genomic regions showed evidence of recent

positive and/or divergent selection and enrichment for associations with adaptive traits that also displayed patterns consistent with natural selection. These regions also provide unexpected

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REVEALS ANCIENT MECHANISMS OF PLANT ADAPTATION TO THE ENVIRONMENT Article Open access 17 February 2025 COMPARATIVE POPULATION GENOMICS IN _TABEBUIA_ ALLIANCE SHOWS EVIDENCE OF ADAPTATION IN

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Article  PubMed  PubMed Central  Google Scholar  Download references ACKNOWLEDGEMENTS We thank the members of BioEnergy Science Center for their varied contributions to this work, and

especially those involved in the collection, propagation and maintenance of the common gardens, including G. Howe, A. Groover, R. Stettler, J. Johnson and the staff at Mt. Jefferson Farms

and Greenwood Resources. We thank the West Virginia University High Performance Computing facility, in particular N. Gregg and M. Carlise. _P. balsamifera_ transcriptomes were provided by M.

Olson (Texas Tech University). This work was supported by funding from the BioEnergy Science Center, a US Department of Energy (DOE) Bioenergy Research Center supported by the Office of

Biological and Environmental Research in the DOE Office of Science. A.M.B. acknowledges support from the Virginia Agricultural Experiment Station and the McIntire Stennis Program of the

National Institute of Food and Agriculture, US Department of Agriculture. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Biology, West Virginia University, Morgantown, West

Virginia, USA Luke M Evans, Eli Rodgers-Melnick & Stephen P DiFazio * Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK Gancho T Slavov *

The Joint Genome Institute, Walnut Creek, California, USA Joel Martin, Wendy Schackwitz & Gerald A Tuskan * BioSciences Division, Plant Systems Biology Group, Oak Ridge National

Laboratory, Oak Ridge, Tennessee, USA Priya Ranjan, Wellington Muchero, Lee Gunter, Jin-Gui Chen & Gerald A Tuskan * Department of Forest Resources and Environmental Conservation,

Virginia Tech, Blacksburg, Virginia, USA Amy M Brunner Authors * Luke M Evans View author publications You can also search for this author inPubMed Google Scholar * Gancho T Slavov View

author publications You can also search for this author inPubMed Google Scholar * Eli Rodgers-Melnick View author publications You can also search for this author inPubMed Google Scholar *

Joel Martin View author publications You can also search for this author inPubMed Google Scholar * Priya Ranjan View author publications You can also search for this author inPubMed Google

Scholar * Wellington Muchero View author publications You can also search for this author inPubMed Google Scholar * Amy M Brunner View author publications You can also search for this author

inPubMed Google Scholar * Wendy Schackwitz View author publications You can also search for this author inPubMed Google Scholar * Lee Gunter View author publications You can also search for

this author inPubMed Google Scholar * Jin-Gui Chen View author publications You can also search for this author inPubMed Google Scholar * Gerald A Tuskan View author publications You can

also search for this author inPubMed Google Scholar * Stephen P DiFazio View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS G.A.T., S.P.D.,

G.T.S. and L.M.E. conceived and designed the study. All authors performed measurements. L.G., J.M. and W.S. performed sequencing. L.M.E., S.P.D., G.T.S., E. R.-M., J.M., P.R., W.M. and W.S.

performed analyses. L.M.E., S.P.D. and A.M.B. drafted the manuscript. All authors read, revised, and approved the manuscript. CORRESPONDING AUTHOR Correspondence to Stephen P DiFazio. ETHICS

DECLARATIONS COMPETING INTERESTS The authors declare no competing financial interests. SUPPLEMENTARY INFORMATION SUPPLEMENTARY TEXT AND FIGURES Supplementary Figures 1–18 and Supplementary

Note. (PDF 12507 kb) SUPPLEMENTARY TABLES 1–12, 14 AND 15 (XLSX 2709 KB) SUPPLEMENTARY TABLE 13 List of SNPs and their associated _P_ values for phenotypic associations as determined by the

emmax mixed model analysis. The nearest predicted gene is listed, as well as annotations of predicted SNP effects for those that fall within genes, as determined by the SNPeff program. When

a SNP lies within two or more genes, additional distance to gene and gene model columns are added before the snpEFF annotation column. (XLSX 5856 kb) SOURCE DATA SOURCE DATA TO FIG. 1 SOURCE

DATA TO FIG. 2 SOURCE DATA TO FIG. 3 RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Evans, L., Slavov, G., Rodgers-Melnick, E. _et al._ Population

genomics of _Populus trichocarpa_ identifies signatures of selection and adaptive trait associations. _Nat Genet_ 46, 1089–1096 (2014). https://doi.org/10.1038/ng.3075 Download citation *

Received: 22 May 2014 * Accepted: 30 July 2014 * Published: 24 August 2014 * Issue Date: October 2014 * DOI: https://doi.org/10.1038/ng.3075 SHARE THIS ARTICLE Anyone you share the following

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