10.1371/journal.pone.0129861 Sara López-Vinyallonga Sara López-Vinyallonga Ignasi Soriano Ignasi Soriano Alfonso Susanna Alfonso Susanna Josep Maria Montserra Josep Maria Montserra Cristina Roquet Cristina Roquet Núria Garcia-Jacas Núria Garcia-Jacas The Polyploid Series of the <i>Achillea millefolium</i> Aggregate in the Iberian Peninsula Investigated Using Microsatellites Public Library of Science 2015 Iberian Peninsula 26 Iberian populations Iberian Peninsula Investigated ploidy levels panmictic yarrow population Achillea millefolium 2015-06-19 03:51:04 Dataset https://plos.figshare.com/articles/dataset/The_Polyploid_Series_of_the_Achillea_millefolium_Aggregate_in_the_Iberian_Peninsula_Investigated_Using_Microsatellites/1455353 <div><p>The <i>Achillea millefolium</i> aggregate is one of the most diverse polyploid complexes of the Northern hemisphere and has its western Eurasian boundary in the Iberian Peninsula. Four ploidy levels have been detected in <i>A</i>. <i>millefolium</i>, three of which have already been found in Iberia (diploid, hexaploid and octoploid), and a fourth (tetraploid) reported during the preparation of this paper. We collected a sample from 26 Iberian populations comprising all ploidy levels, and we used microsatellite markers analyzed as dominant in view of the high ploidy levels. Our goals were to quantify the genetic diversity of <i>A</i>. <i>millefolium</i> in the Iberian Peninsula, to elucidate its genetic structure, to investigate the differences in ploidy levels, and to analyse the dispersal of the species. The lack of spatial genetic structure recovered is linked to both high levels of gene flow between populations and to the fact that most genetic variability occurs within populations. This in turn suggests the existence of a huge panmictic yarrow population in the Iberian Peninsula. This is consistent with the assumption that recent colonization and rapid expansion occurred throughout this area. Likewise, the low levels of genetic variability recovered suggest that bottlenecks and/or founder events may have been involved in this process, and clonal reproduction may have played an important role in maintaining this genetic impoverishment. Indeed, the ecological and phenologic uniformity present in the <i>A</i>. <i>millefolium</i> agg. in Iberia compared to Eurasia and North America may be responsible for the low number of representatives of this complex of species present in the Iberian Peninsula. The low levels of genetic differentiation between ploidy levels recovered in our work suggest the absence of barriers between them.</p></div>