DOI: 10.5061/dryad.ff1g6
title: Data from: Distribution and drivers of ectomycorrhizal fungal communities across the North American Arctic

description: Ectomycorrhizal fungi (EMF) form symbioses with a few plant species that
 comprise a large fraction of the arctic vegetation. Despite their
 importance, the identity, abundance and distribution of EMF in the Arctic,
 as well as the key drivers controlling their community composition are
 poorly understood. In this study, we investigated the diversity and
 structure of EMF communities across a bioclimatic gradient spanning much
 of the North American Arctic. We collected roots from two principal arctic
 ectomycorrhizal host plants, Salix arctica and Dryas integrifolia,
 typically growing intermingled, at 23 locations stratified across the five
 bioclimatic subzones of the Arctic. DNA was extracted from ectomycorrhizal
 root tips and the ITS region was sequenced and phylogenetically analyzed.
 A total of 242 fungal Operational Taxonomic Units (OTUs) were documented,
 with 203 OTUs belonging to the Basidiomycota and 39 to the Ascomycota,
 exceeding the number of previously morphologically described EMF in the
 Arctic. EMF communities were dominated by a few common and species-rich
 families such as Thelephoraceae, Inocybaceae, Sebacinaceae,
 Cortinariaceae, and Pyronemataceae. Both host plants showed similar
 species richness, with 176 OTUs on Salix arctica and 154 OTUs on Dryas
 integrifolia. Host plant identity did not affect EMF community
 composition. The ten most abundant OTUs had a wide geographic distribution
 throughout the Arctic, and were also found in boreal, temperate and
 Mediterranean regions, where they were associated with a variety of hosts.
 Species richness did not decline with increasing latitude. However, EMF
 community structure changed gradually across the bioclimatic gradient with
 the greatest similarity between neighboring bioclimatic subzones and
 locations. EMF community structure was correlated with environmental
 factors at a regional scale, corresponding to a complex of glaciation
 history, geology, soil properties, plant productivity and climate. This is
 the first large-scale study of EMF communities across all five bioclimatic
 subzones of the North American Arctic, accompanied by an extensive set of
 environmental factors analyzed to date. While our study provides baseline
 data to assess shifts of plant and fungi distribution in response to
 climate change, it also suggests that with ongoing climate warming, EMF
 community composition may be affected by northward shifts of some taxa.
description: Maximum likelihood
 phylograms and their alignment files for ectomycorrhizal fungi associated
 with Salix arctica and Dryas integrifolia across the North American
 Arctic.Maximum-likelihood
 phylograms (pdf) of (1) Tomentella1, (2) Tomentella 2, (3)
 Pseudotomentella, (4) Inocybe 1, (5) Inocybe 2, (6) Inocybe 3, (7) Inocybe
 4, (8) Inocybe 5, (9) Sebacina 1, (10) Sebacina 2, (11) Sebacina 3, (12)
 Cortinarius 1, (13) Cortinarius 2, (14) Cortinarius 3, (15) Cortinarius 4,
 (16) Clavulina, (17) Russula, (18) Tulasnella, (19) Ceratobasidium, (20)
 Entoloma, (21) Hebeloma, (22) Lactarius, (23) Laccaria, (24)
 Pyronemataceae, (25) Tuber, (26) Tuberaceae, (27) Sordariaceae, (28)
 Phialocephala, (29) Cenococcum, (30) Angulospora, (31) Hymenoscyphus, (32)
 Leohumicola, (33) Cadophora, (34) Leptodontidium, (35) Peziza, (36)
 Balsamia, (37) Tetracladium. taxa inferred from the ITS rDNA datasets
 showing the phylogenetic spread of the OTUs observed in our study
 (highlighted by a grey box), including their presence across the
 bioclimatic subzones of the Arctic among representatives of congeneric
 taxa in GenBank. Branches with ≥ 90% bootstrap support are highlighted.
 Each phylogram is accompanied by the sequence alignment files (nex) used
 for each phylogram.Archive.zip