Open Collections

Germain, Hugo; Bergeron, Marie-Josée; Bernier, Louis; Laflamme, Gaston; Hamelin, Richard C

<b>Abstract</b><br/>The basidiomycetous fungus Onnia tomentosa is one of the most widespread root rot pathogens in North America. Although the disease is more severe on spruce and pine trees, this pathogen can infect several coniferous species. In order to study the population structure of O. tomentosa, we harvested 180 basidiocarps in a 45-year-old white spruce plantation in western Quebec in autumn 1997, and extracted DNA directly from individual basidiocarps. Using a combination of spatial coordinates and molecular data based on the analysis of two mitochondrial and three nuclear loci, we measured the average genet size and molecular diversity and assessed the relative contribution of basidiospores and vegetative growth to the stand colonization. Most of the sampled basidiocarps that clustered spatially belonged to the same genet. A total of thirty-seven discrete multilocus genets of an average size of 3.42 m were obtained. The genet size distribution was skewed toward smaller genets (< 3 m) that displayed higher diversity than the larger genets (> 3 m). The nuclear loci were in Hardy-Weinberg equilibrium in the larger genets, but not in the smaller genets, which displayed a deficiency of heterozygotes. This suggests a Wahlund effect, whereby different colonization events resulted in expected heterozygosity higher than observed heterozygosity. Using an estimate of the growth rate of the fungus, only a few of the largest genets were approximately the age of the plantation. These observations are consistent with the colonization by basidiospores subsequent to site preparation and tree planting followed by secondary colonization events and vegetative spread.; <b>Usage notes</b><br /><div class="o-metadata__file-usage-entry"><h4 class="o-heading__level3-file-title">CLones_3_MJB</h4><div class="o-metadata__file-description">Multilocus Genotypes of fungus, with size of clones in bins of 3 m</div><div class="o-metadata__file-name"></div></div><div class="o-metadata__file-usage-entry"><h4 class="o-heading__level3-file-title">IT_Act_MJB</h4><div class="o-metadata__file-description">Phylip file of Actin gene sequence. No clone correction.</div><div class="o-metadata__file-name"></div></div><div class="o-metadata__file-usage-entry"><h4 class="o-heading__level3-file-title">IT_BT_MJB</h4><div class="o-metadata__file-description">Phylip file of Beta-tubulin sequence, no clone-correction</div><div class="o-metadata__file-name"></div></div><div class="o-metadata__file-usage-entry"><h4 class="o-heading__level3-file-title">IT_RPB1_MJB</h4><div class="o-metadata__file-description">Phylip file of Onnia tomentosa, individual sequence of carpophores</div><div class="o-metadata__file-name"></div></div>

western Quebec

Dryad version number: 1</p>

Version status: submitted</p>

Dryad curation status: Published</p>

Sharing link: https://datadryad.org/stash/share/m3A-x5sZxFy3aHuISYH2JrcdY2X7QjlSyMKcuL-m6DY</p>

Storage size: 136181</p>

Visibility: public</p>

University of British Columbia Library

10.14288/1.0397718

https://doi.org/10.5683/SP2/HK4LFS; https://doi.org/10.5061/dryad.8281

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