Phylogenetic and ecological analyses of soil and sporocarp DNA sequences reveal high diversity and strong habitat partitioning in the boreal ectomycorrhizal genus Russula (Russulales; Basidiomycota).
*Although critical for the functioning of ecosystems, fungi are poorly known in high-latitude regions. Here, we provide the first genetic diversity assessment of one of the most diverse and abundant ectomycorrhizal genera in Alaska: Russula. *We analyzed internal transcribed spacer rDNA sequences from sporocarps and soil samples using phylogenetic methods, operational taxonomic unit (OTU) delimitations and ordinations to compare species composition in various types of boreal forest. *The genus Russula is highly diverse in Alaska, with at least 42 nonsingleton OTUs (soil) and 50 phylogroups (soil + sporocarp). Russula taxa showed strong habitat preference to one of the two major forest types in the sampled regions (black spruce and birch-aspen-white spruce), and some preference for soil horizon. *Our results show that the vast majority of Russula species are present in the soil samples, although some additional taxa are expected to be found with extended sampling. OTU diversity in black spruce forests was only one-third of the diversity observed in mixed upland forests. Our findings suggest that some of the diversity is niche based, especially along host and successional axes, because most OTUs predictably occurred in specific habitats, regardless of geographical location.
Geml
József
J
Institute of Arctic Biology, 311 Irving I Building, 902 N. Koyukuk Drive, P.O. Box 757000, University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA.|Present address: National Herbarium of the Netherlands, Netherlands Centre for Biodiversity Naturalis, Leiden University, Einsteinweg 2, P.O. Box 9514, 2300 RA Leiden, the Netherlands.
Laursen
Gary A
GA
Institute of Arctic Biology, 311 Irving I Building, 902 N. Koyukuk Drive, P.O. Box 757000, University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA.
Herriott
Ian C
IC
Institute of Arctic Biology, 311 Irving I Building, 902 N. Koyukuk Drive, P.O. Box 757000, University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA.
McFarland
Jack M
JM
Institute of Arctic Biology, 311 Irving I Building, 902 N. Koyukuk Drive, P.O. Box 757000, University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA.
Booth
Michael G
MG
Institute of Arctic Biology, 311 Irving I Building, 902 N. Koyukuk Drive, P.O. Box 757000, University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA.
Lennon
Niall
N
Sequence and Analysis Program, Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA.
Chad Nusbaum
H
H
Sequence and Analysis Program, Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA.
Lee Taylor
D
D
Institute of Arctic Biology, 311 Irving I Building, 902 N. Koyukuk Drive, P.O. Box 757000, University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA.
D000413:Alaska; D001483:Base Sequence; D001487:Basidiomycota / Q000145:classification / Q000235:genetics*; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D017753:Ecosystem; D014644:Genetic Variation; D016013:Likelihood Functions; D038821:Mycorrhizae / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D010944:Plants / Q000382:microbiology; D012988:Soil Microbiology; D013045:Species Specificity
D021903:DNA, Ribosomal Spacer