Principal Coordinates Analysis (PCoA) plot of the first and the second principal coordinates based on the genetic composition at six nuclear microsatellites of 42 population samples of common ash (<i>Fraxinus excelsior</i>).

<p>For population names see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.s001" target="_blank">S1 Table</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.s006" target="_blank">S1 Fig</a>. Each population is given the color of the STRUCTURE group (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.g002" target="_blank">Fig 2C</a>) in which it had the highest proportion of membership (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.s001" target="_blank">S1 Table</a>).</p

Pearson’s correlation coefficients (r) between allelic richness (<i>A</i>r), gene diversity (<i>H</i>_E), inbreeding coefficient calculated with INEST (<i>F</i>_ISINEST), latitude and longitude calculated for populations within: (i) Europe overall, (ii) TESS group 2 (constituting populations from northern and eastern Europe, see S1 Table), and (iii) Norway.

<p>Pearson’s correlation coefficients (r) between allelic richness (<i>A</i>r), gene diversity (<i>H</i>_E), inbreeding coefficient calculated with INEST (<i>F</i>_ISINEST), latitude and longitude calculated for populations within: (i) Europe overall, (ii) TESS group 2 (constituting populations from northern and eastern Europe, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.s001" target="_blank">S1 Table</a>), and (iii) Norway.</p

Distribution of chloroplast haplotypes in 42 common ash (<i>Fraxinus excelsior</i>) population samples.

<p>Coding of the haplotypes follows Heuertz <i>et al</i>. [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.ref041" target="_blank">41</a>] and Sutherland <i>et al</i>. [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.ref033" target="_blank">33</a>], except for the novel haplotypes H17, H18 and H19. The definitions of the haplotypes are given in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.t001" target="_blank">Table 1</a>. The shaded gray areas represent the natural distribution range of common ash [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.ref029" target="_blank">29</a>].</p

Genetic Structure in the Northern Range Margins of Common Ash, <i>Fraxinus excelsior</i> L. - Fig 4

<p><b>Linear regression between allelic richness and latitude for common ash (<i>Fraxinus excelsior</i>) populations a) across Europe overall, b) across northern and eastern European populations putatively constituting colonization from south-eastern Europe northwards (TESS group 2) and c) across Norwegian populations.</b> Allelic richness is calculated based on a random set of 13 diploid individuals per population.</p

Basic characteristics of the six nuclear microsatellite loci in <i>Fraxinus excelsior</i> used in this study.

<p><i>A</i>r, allelic richness, calculated based on 13 diploid individuals; <i>H</i>_O, observed heterozygosity; <i>H</i>_E, expected heterozygosity; <i>F</i>_IS, inbreeding coefficient (the coefficients denoted with asterisk (*) are significantly greater than zero); <i>F</i>_ST, coefficient of genetic differentiation among populations [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.ref063" target="_blank">63</a>]; and <i>F</i>_STENA, coefficient of genetic differentiation calculated using ENA correction [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0167104#pone.0167104.ref056" target="_blank">56</a>].</p