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Joseph W Spatafora - One of the best experts on this subject based on the ideXlab platform.
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out of western north america evolution of the Rhizopogon pseudotsuga symbiosis inferred by genome scale sequence typing
Fungal Ecology, 2019Co-Authors: Alija Bajro Mujic, Kentaro Hosaka, Bo Huang, Mingjun Chen, Pihan Wang, David S Gernandt, Joseph W SpataforaAbstract:Abstract Mutual dependence and shared geographic distributions of ectomycorrhizal fungi and their hosts suggest that comigration has had an influential role in the evolution of the ectomycorrhizal symbiosis. To test the hypothesis of comigration of ectomycorrhizal symbionts we conducted a phylogeographic analysis of host specific ectomycorrhizal fungi in genus Rhizopogon sampled throughout the natural range of their Pseudotsuga (Douglas fir) hosts. Low coverage genome assemblies were sequenced for all Rhizopogon species-level clades and a novel data mining method, genome-scale sequence typing, was developed to produce a genome-scale phylogenetic dataset. Phylogenetic and phylogeographic analyses support a single evolutionary origin of the Rhizopogon-Pseudotsuga ectomycorrhizal symbiosis in coastal western North America with a single migration into Asia and two independent migrations east into the North American Intermountain West. Our results suggest that the Rhizopogon-Pseudotsuga ectomycorrhizal symbiosis predates species radiation in Pseudotsuga and that these genera have undergone processes of comigration and codiversification.
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the cedrus associated truffle trappeindia himalayensis is a morphologically unique and phylogenetically divergent species of Rhizopogon
Mycologia, 2019Co-Authors: Alija B Mujic, Joseph W Spatafora, Nan Zheng, Michael A Castellano, Matthew E SmithAbstract:: In the northwestern Himalayan mountains of India, the hypogeous sequestrate fungus Trappeindia himalayensis is harvested from forests dominated by the ectomycorrhizal tree Cedrus deodara (Himalayan cedar). This truffle has basidiospores that are ornamented with raised reticulation. The original description of Trappeindia himalayensis suggested that the gleba of this species is similar to young specimens of Scleroderma (Boletales), whereas its basidiospores are ornamented with raised reticulation, suggesting a morphological affinity to Leucogaster (Russulales) or Strobilomyces (Boletales). Given this systematic ambiguity, we have generated DNA sequence data from type material and other herbarium specimens and present the first molecular phylogenetic analysis of this unusual Cedrus-associated truffle. Despite the irregular ornamented basidiospore morphology, T. himalayensis is resolved within the genus Rhizopogon (Suillineae, Boletales) and represents a unique lineage that has not been previously detected. All known Rhizopogon species possess an ectomycorrhizal trophic mode, and because of its placement in this lineage, it is likely that Trappeindia himalayensis is an ectomycorrhizal partner of Cedrus deodara. This study highlights the importance of generating sequence data from herbarium specimens in order to identify fungal biodiversity and clarify the systematic relationships of poorly documented fungi.
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comparative genomics of the ectomycorrhizal sister species Rhizopogon vinicolor and Rhizopogon vesiculosus basidiomycota boletales reveals a divergence of the mating type b locus
G3: Genes Genomes Genetics, 2017Co-Authors: Alija Bajro Mujic, Andrew Tritt, Anna Lipzen, Cindy Chen, Jenifer Johnson, Aditi Sharma, Kerrie Barry, Igor V Grigoriev, Joseph W SpataforaAbstract:Divergence of breeding system plays an important role in fungal speciation. Ectomycorrhizal fungi, however, pose a challenge for the study of reproductive biology because most cannot be mated under laboratory conditions. To overcome this barrier, we sequenced the draft genomes of the ectomycorrhizal sister species Rhizopogon vinicolor Smith and Zeller and R. vesiculosus Smith and Zeller (Basidiomycota, Boletales)—the first genomes available for Basidiomycota truffles—and characterized gene content and organization surrounding their mating type loci. Both species possess a pair of homeodomain transcription factor homologs at the mating type A-locus as well as pheromone receptor and pheromone precursor homologs at the mating type B-locus. Comparison of Rhizopogon genomes with genomes from Boletales, Agaricales, and Polyporales revealed synteny of the A-locus region within Boletales, but several genomic rearrangements across orders. Our findings suggest correlation between gene content at the B-locus region and breeding system in Boletales with tetrapolar species possessing more diverse gene content than bipolar species. Rhizopogon vinicolor possesses a greater number of B-locus pheromone receptor and precursor genes than R. vesiculosus, as well as a pair of isoprenyl cysteine methyltransferase genes flanking the B-locus compared to a single copy in R. vesiculosus. Examination of dikaryotic single nucleotide polymorphisms within genomes revealed greater heterozygosity in R. vinicolor, consistent with increased rates of outcrossing. Both species possess the components of a heterothallic breeding system with R. vinicolor possessing a B-locus region structure consistent with tetrapolar Boletales and R. vesiculosus possessing a B-locus region structure intermediate between bipolar and tetrapolar Boletales.
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Rhizopogon togasawariana sp nov the first report of Rhizopogon associated with an asian species of pseudotsuga
Mycologia, 2014Co-Authors: Alija Bajro Mujic, Kentaro Hosaka, Joseph W SpataforaAbstract:Rhizopogon subgenus Villosuli are the only members of the genus known to form an ectomycor- rhizal relationship exclusively with Pseudotsuga. The specificity of this host relationship is unusual in that Rhizopogon is broadly associated with several tree genera within the Pinaceae and relationships with a host genus are typically distributed across Rhizopogon subgenera. Naturally occurring specimens of R. subg. Villosuli have been described only from North American collections, and the unique host relation- ship with Pseudotsuga is demonstrated only for Rhizopogon associated with P. menziesii (Douglas-fir), the dominant species of Pseudotsuga in North America. Species of Pseudotsuga are naturally distrib- uted around the northern Pacific Rim, and Rhizopo- gon associates of other Pseudotsuga spp. are not yet described. Here we present the results of field sampling conducted in P. japonica forests throughout the Japanese archipelago and describe Rhizopogon togasawariana sp. nov., which occurs in ectomycor- rhizal association with P. japonica. Placement of this new species within R. subg. Villosuli is supported by morphological and molecular phylogenetic analysis, and its implications to Pseudotsuga-Rhizopogon bioge- ography are discussed.
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short title spatial analysis of Rhizopogon genotypes within population genetic structure differs between two sympatric sister species of ectomycorrhizal fungi Rhizopogon vinicolor and r vesiculosus
2013Co-Authors: Susie Dunham, Alija Bajro Mujic, Joseph W Spatafora, Annette M KretzerAbstract:Within-population genetic structure differs between two sympatric sister-species of ectomycorrhizal fungi, Rhizopogon vinicolor and R. vesiculosus Susie M. Dunham Willamette University, Department of Biology, 900 State Street, Salem, Oregon 97301 Alija Bajro Mujic Joseph W. Spatafora Oregon State University, Department of Botany and Plant Pathology, 2082 Cordley Hall Corvallis, Oregon 97331 Annette M. Kretzer SUNY College of Environmental Science and Forestry, Faculty of Environmental and Forest Biology, 1 Forestry Drive, Syracuse, New York 13210 Abstract: Using spatial autocorrelation analysis, we examined the within-population genetic structure of Rhizopogon vinicolor and R. vesiculosus, two hypogeous ectomycorrhizal (EM) species that are sympatric sister taxa known to differ in their clonal structure. We collected 121 sporocarps and 482 tuberculate EM of both species from a 20 ha forest stand dominated by Douglas-fir (Pseudotsuga menziesii). Field collections were identified to species with restriction fragment length polymorphism analysis of the nuclear ribosomal internal transcribed spacer. Five and six microsatellite markers were used to characterize the genetic diversity of EM and sporocarp samples from R. vesiculosus and R. vinicolor respectively. After correcting for genet structure, spatial autocorrelation analyses of the EM samples were used to test the null hypothesis that multilocus genotypes characterized from each species were randomly distributed In Press at Mycologia, preliminary version published on May 24, 2013 as doi:10.3852/12-265
Randy Molina - One of the best experts on this subject based on the ideXlab platform.
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patterns of vegetative growth and gene flow in Rhizopogon vinicolor and r vesiculosus boletales basidiomycota
Molecular Ecology, 2005Co-Authors: Annette M Kretzer, Randy Molina, Susie M Dunham, Joseph W SpataforaAbstract:We have collected sporocarps and tuberculate ectomycorrhizae of both Rhizopogon vinicolor and Rhizopogon vesiculosus from three 50 × 100 m plots located at Mary’s Peak in the Oregon Coast Range (USA); linear map distances between plots ranged from c . 1 km to c . 5.5 km. Six and seven previously developed microsatellite markers were used to map the approximate size and distribution of R. vinicolor and R. vesiculosus genets, respectively. Genetic structure within plots was analysed using spatial autocorrelation analyses. No significant clustering of similar genotypes was detected in either species when redundant samples from the same genets were culled from the data sets. In contrast, strong clustering was detected in R. vesiculosus when all samples were analysed, but not in R. vinicolor . These results demonstrate that isolation by distance does not occur in either species at the intraplot sampling scale and that clonal propagation (vegetative growth) is significantly more prevalent in R. vesiculosus than in R. vinicolor . Significant genetic differentiation was detected between some of the plots and appeared greater in the more clonal species R. vesiculosus with Φ Φ Φ ST values ranging from 0.010 to 0.078*** than in R. vinicolor with Φ ST values ranging from − − − 0.002 to 0.022** (* P < 0.05, ** P < 0.01, *** P < 0.001). When tested against the null hypothesis of no relationship between individuals, parentage analysis detected seven likely parent/offspring pairs in R. vinicolor and four in R. vesiculosus (α α α = 0.001). Of these 11 possible parent/offspring pairs, only two R. vinicolor pairs were still supported as parent/offspring when tested against the alternative hypothesis of being full siblings (α = 0.05). In the latter two cases, parent and offspring were located at approximately 45 m and 28 m from each other. Challenges to parentage analysis in ectomycorrhizal fungi are discussed.
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microsatellite markers reveal the below ground distribution of genets in two species of Rhizopogon forming tuberculate ectomycorrhizas on douglas fir
New Phytologist, 2003Co-Authors: Annette M Kretzer, Randy Molina, Susie Dunham, Joseph W SpataforaAbstract:Summary • We have developed microsatellite markers for two sister species of Rhizopogon, R. vesiculosus and R. vinicolor (Boletales, Basidiomycota), and used selected markers to investigate genet size and distribution from ectomycorrhizal samples. Both species form ectomycorrhizas with tuberculate morphology on Douglas-fir (Pseudotsuga menziesii). • Tuberculate ectomycorrhizas were sampled and mapped in two 10 × 10 m core plots located at Mary's Peak in the Oregon Coast Range and at Mill Creek in the Oregon Cascade Mountains, USA; additional samples were obtained from a larger area surrounding the Mary's Peak core plot. • Gene diversities at the newly described microsatellite loci ranged from 0.00 to 0.68 in R. vesiculosus, and from 0.00 to 0.43 in R. vinicolor. Both taxa appeared to be in Hardy–Weinberg and linkage equilibrium. The largest distance observed between tuberculate ectomycorrhizas of the same genet was 13.4 m for R. vesiculosus, but only 2 m for R. vinicolor. • This is to our knowledge the first study to differentiate fungal genets from ectomycorrhizas with great confidence using multiple codominant markers.
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taxonomy of the Rhizopogon vinicolor species complex based on analysis of its sequences and microsatellite loci
Mycologia, 2003Co-Authors: Annette M Kretzer, Randy Molina, Daniel L Luoma, Joseph W SpataforaAbstract:We are re-addressing species concepts in the Rhizopogon vinicolor species complex (Boletales, Basidiomycota) using sequence data from the internal-transcribed spacer (ITS) region of the nuclear ribosomal repeat, as well as genotypic data from five microsatellite loci. The R. vinicolor species complex by our definition includes, but is not limited to, collections referred to as R. vinicolor Smith, R. diabolicus Smith, R. ochraceisporus Smith, R. parvulus Smith or R. vesiculosus Smith. Holo- and/or paratype material for the named species is included. Analyses of both ITS sequences and microsatellite loci separate collections of the R. vinicolor species complex into two distinct clades or clusters, suggestive of two biological species that subsequently are referred to as R. vinicolor sensu Kretzer et al and R. vesiculosus sensu Kretzer et al. Choice of the latter names, as well as morphological characters, are discussed.
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biology of the ectomycorrhizal genus Rhizopogon vi re examination of infrageneric relationships inferred from phylogenetic analyses of its sequences
Mycologia, 2002Co-Authors: Lisa C Grubisha, Randy Molina, James M Trappe, Joseph W SpataforaAbstract:Rhizopogon (Basidiomycota, Boletales) is a genus of hypogeous fungi that form ectomycorrhizal associations mostly with members of the Pinaceae. This genus comprises an estimated 100+ species, with ...
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biology of the ectomycorrhizal genus Rhizopogon v phylogenetic relationships in the boletales inferred from lsu rdna sequences
Mycologia, 2001Co-Authors: Lisa C Grubisha, Randy Molina, James M Trappe, Joseph W SpataforaAbstract:The phylogenetic relationship between Al- pova, Chroogomphus, Gomphidius, Rhizopogon, Suil- lus, and Truncocolumella and their placement in the Boletales was tested through maximum parsimony analyses of large subunit nuclear ribosomal DNA se- quences. Taxon sampling included representatives of the genera Alpova, Boletellus, Boletus, Chroogomphus, Gomphidius, Melanogaster, Paragyrodon, Phylloporus, Rhizopogon, Suillus, Truncocolumella, Tylopilus, and Xerocomus, as well as species from the Agaricales, Rus- sulales, and Polyporales. The order Boletales was strongly supported as monophyletic. Furthermore, within this order, two major groups emerged: the bol- etoid radiation and a Melanogastraceae/Paragyrodon sphaerosporus paraphyletic assemblage, and the suil- loid radiation. The boletoid radiation and a Melan- both within and outside the suilloid radiation. Within the suilloid radiation, Suillus was inferred to be more closely related to Truncocolumella citrina and the Gomphidiaceae than to Rhizopogon, suggesting a more distant relationship between Suillus and Rhi- zopogon than previously hypothesized. Rhizopogon was not supported as monophyletic, although its mono- phyly could not be rejected by the data. Alpova oli- vaceotinctus grouped within the genus Rhizopogon, consistent with previous classifications, and is re- turned to that genus.
Thomas D Bruns - One of the best experts on this subject based on the ideXlab platform.
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inoculum potential of Rhizopogon spores increases with time over the first 4 yr of a 99 yr spore burial experiment
New Phytologist, 2009Co-Authors: Thomas D Bruns, Primrose J Boynton, Lisa C Grubisha, Nicole A Hynson, Nhu H Nguyen, Kabir G Peay, Nicholas P RosenstockAbstract:Summary • In disturbed or pioneer settings, spores and sclerotia of ectomycorrhizal fungi serve as the necessary inoculum for establishment of ectomycorrhizal-dependent trees. Yet, little is known about the persistence of these propagules through time. • Here, live field soil was inoculated with known quantities of basidiospores from four pine-associated species of Rhizopogon; these samples were then buried in retrievable containers, and pine seedling bioassays of serially diluted spore samples were used to measure spore viability. • In the first 4 yr, no evidence of loss of spore viability was found in the four Rhizopogon species tested, but all four species exhibited dormancy in which a maximum of 1–8% of their spores were initially receptive to pine roots. There were some differences between species in overall inoculum potential of their spores, but all species broke dormancy at a statistically similar rate. • This result provides evidence for spore dormancy in a common ectomycorrhizal genus, but it also precludes our ability to estimate the longevity of the spores accurately. Nevertheless these results, coupled with the observed patterns of Rhizopogon spore banks, suggest that at least decade-long durations are likely. As this experiment progresses, the true longevity of the spores will eventually be revealed.
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host islands within the california northern channel islands create fine scale genetic structure in two sympatric species of the symbiotic ectomycorrhizal fungus Rhizopogon
Molecular Ecology, 2007Co-Authors: Lisa C Grubisha, Sarah E Bergemann, Thomas D BrunsAbstract:We have examined fine-scale genetic structure of the symbiotic ectomycorrhizal fungi Rhizopogon occidentalis and R. vulgaris on two of the California Channel Islands using five and six microsatellite loci, respectively. Both Rhizopogon species are sympatric on Santa Cruz and Santa Rosa Islands and are ectomycorrhizal with bishop pine ( Pinus muricata ) on both islands or Santa Rosa Island Torrey pine ( P. torreyana ssp. insularis ) on Santa Rosa. The combination of disjunct pine host distributions and geographic barriers within and among the islands have created highly structured Rhizopogon populations over very short distances (8.5 km on Santa Cruz Island; F ST = 0.258, F ST = 0.056, R. occidentalis and R. vulgaris , respectively). Both species show similar patterns of genetic differentiation as a result of limited dispersal between host populations as revealed by a significant isolation by distance relationship ( r = 0.69, P < 0.04; r = 0.93, P < 0.001, R. occidentalis and R. vulgaris , respectively) and Bayesian clustering analyses, and is most likely a function of the small foraging range of the few mammals that disperse Rhizopogon on these islands and the enormous spore bank characteristic of Rhizopogon species.
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determining the outcome of field based competition between two Rhizopogon species using real time pcr
Molecular Ecology, 2006Co-Authors: Peter G Kennedy, Sarah E Bergemann, Sara Hortal, Thomas D BrunsAbstract:Interest in the ecology of ectomycorrhizal (ECM) fungi has increased considerably, but little is known about interspecific interactions among ECM species. We examined competitive interactions between Rhizopogon occidentalis and R. salebrosus at Point Reyes National Seashore, California, USA. At three field sites, species abundances were compared in single- and two-species treatments on Pinus muricata seedlings inoculated with spores. Competition for root tips was assessed using real-time polymerase chain reaction (PCR) of internal transcribed spacer rDNA. In general, we found strong competitive exclusion of R. salebrosus by R. occidentalis , with ≥ 75% of the seedlings in the two-species treatment colonized exclusively by R. occidentalis after 5 and 10 months. However, on the seedlings that were co-colonized, we observed no significant difference in the abundances of R. salebrosus and R. occidentalis , suggesting that once R. salebrosus was established, it was no longer competitively inferior. There were no significant differences in survival, growth, or percentage leaf nitrogen of seedlings colonized with either Rhizopogon species, but both growth and percentage leaf nitrogen were significantly higher for ECM than non-ECM seedlings. We also observed strong positive correlations between actual ECM root tip weight and that inferred from real-time PCR for both species, indicating that this method provided an accurate assessment of root tip occupation and hence ECM competitive dynamics. In conjunction with a previous experiment, our results indicate that competition between these two Rhizopogon species occurs similarly in both field and laboratory settings and that when colonizing from spore, timing largely determines the outcome of initial competitive interactions.
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the effect of different pine hosts on the sampling of Rhizopogon spore banks in five eastern sierra nevada forests
New Phytologist, 2006Co-Authors: T A Rusca, Peter G Kennedy, Thomas D BrunsAbstract:Summary • Our primary goal was to determine whether detection of Rhizopogon internal transcribed spacer (ITS) groups is affected by the pine species used in seedling bioassays. Our secondary goal was to investigate composition of Rhizopogon spore banks in the Eastern Sierra Nevada of California, a previously unsampled region. • We used seedlings of Pinus contorta, Pinus jeffreyi, Pinus lambertiana, and Pinus muricata as bioassay plants and identified the Rhizopogon retrieved by internal transcribed spacer (ITS) sequence analysis. • We found that each of the pine species retrieved all of the abundant Rhizopogon ITS groups, but there were significant differences among pines in the richness of Rhizopogon ITS groups recovered. Pinus muricata recovered all ITS groups found in this study and was significantly better than P. lambertiana. Rhizopogon communities from the five sampled sites contained six to eight ITS groups per site, with two unique sequence groups and a higher abundance of the Rhizopogon ellenae and Rhizopogon arctostaphyli groups than at previously sampled sites. • These results show high cross-receptivity between Rhizopogon and pine species, and regional patterns in spore bank composition.
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isolation and characterization of microsatellite loci from the truffle like ectomycorrhizal fungi Rhizopogon occidentalis and Rhizopogon vulgaris
Molecular Ecology Notes, 2005Co-Authors: Lisa C Grubisha, Annette M Kretzer, Thomas D BrunsAbstract:We have isolated and characterized five microsatellite loci from Rhizopogon occidentalis and six loci from Rhizopogon vulgaris (Boletales, Basidiomycota). Microsatellite variation was assessed using 32 R. occidentalis and 48 R. vulgaris individuals from four populations in California. The number of alleles across populations ranged from two to 10 for R. occidentalis and three to eight for R. vulgaris . Expected heterozygosity values within populations ranged from 0.00 to 0.85 for R. occidentalis and 0.00 to 0.75 for R. vulgaris . These are the first microsatellite loci isolated for R. occidentalis and R. vulgaris and will be useful in the examination of their population genetic structure.
Annette M Kretzer - One of the best experts on this subject based on the ideXlab platform.
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short title spatial analysis of Rhizopogon genotypes within population genetic structure differs between two sympatric sister species of ectomycorrhizal fungi Rhizopogon vinicolor and r vesiculosus
2013Co-Authors: Susie Dunham, Alija Bajro Mujic, Joseph W Spatafora, Annette M KretzerAbstract:Within-population genetic structure differs between two sympatric sister-species of ectomycorrhizal fungi, Rhizopogon vinicolor and R. vesiculosus Susie M. Dunham Willamette University, Department of Biology, 900 State Street, Salem, Oregon 97301 Alija Bajro Mujic Joseph W. Spatafora Oregon State University, Department of Botany and Plant Pathology, 2082 Cordley Hall Corvallis, Oregon 97331 Annette M. Kretzer SUNY College of Environmental Science and Forestry, Faculty of Environmental and Forest Biology, 1 Forestry Drive, Syracuse, New York 13210 Abstract: Using spatial autocorrelation analysis, we examined the within-population genetic structure of Rhizopogon vinicolor and R. vesiculosus, two hypogeous ectomycorrhizal (EM) species that are sympatric sister taxa known to differ in their clonal structure. We collected 121 sporocarps and 482 tuberculate EM of both species from a 20 ha forest stand dominated by Douglas-fir (Pseudotsuga menziesii). Field collections were identified to species with restriction fragment length polymorphism analysis of the nuclear ribosomal internal transcribed spacer. Five and six microsatellite markers were used to characterize the genetic diversity of EM and sporocarp samples from R. vesiculosus and R. vinicolor respectively. After correcting for genet structure, spatial autocorrelation analyses of the EM samples were used to test the null hypothesis that multilocus genotypes characterized from each species were randomly distributed In Press at Mycologia, preliminary version published on May 24, 2013 as doi:10.3852/12-265
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architecture of the wood wide web Rhizopogon spp genets link multiple douglas fir cohorts
New Phytologist, 2010Co-Authors: Kevin J Beiler, Suzanne W Simard, Daniel M Durall, Sheri A Maxwell, Annette M KretzerAbstract:Summary •The role of mycorrhizal networks in forest dynamics is poorly understood because of the elusiveness of their spatial structure. We mapped the belowground distribution of the fungi Rhizopogon vesiculosus and Rhizopogon vinicolor and interior Douglas-fir trees (Pseudotsuga menziesii var. glauca) to determine the architecture of a mycorrhizal network in a multi-aged old-growth forest. •Rhizopogon spp. mycorrhizas were collected within a 30 × 30 m plot. Trees and fungal genets were identified using multi-locus microsatellite DNA analysis. Tree genotypes from mycorrhizas were matched to reference trees aboveground. Two trees were considered linked if they shared the same fungal genet(s). •The two Rhizopogon species each formed 13–14 genets, each colonizing up to 19 trees in the plot. Rhizopogon vesiculosus genets were larger, occurred at greater depths, and linked more trees than genets of R. vinicolor. Multiple tree cohorts were linked, with young saplings established within the mycorrhizal network of Douglas-fir veterans. A strong positive relationship was found between tree size and connectivity, resulting in a scale-free network architecture with small-world properties. •This mycorrhizal network architecture suggests an efficient and robust network, where large trees play a foundational role in facilitating conspecific regeneration and stabilizing the ecosystem.
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Bacterial communities associated with tuberculate ectomycorrhizae of Rhizopogon spp.
Mycorrhiza, 2009Co-Authors: Annette M Kretzer, Zachary R. KingAbstract:We have previously reported the design of a new PCR primer pair that allows amplification of a broad range of eubacterial 16S rDNA sequences from ectomycorrhizae (ECM) without co-amplification of plastid or mitochondrial sequences. Here, we report using a similar primer combination to generate three small 16S rDNA libraries from tuberculate ECM of Rhizopogon spp., two from R. vinicolor ECM (libraries Rvi18 and Rvi24) and one from R. vesiculosus ECM (library Rve13). At the class level, libraries were dominated by sequences from the Alphaproteobacteria , Gammaproteobacteria , and Acidobacteria , with some Sphingobacteria , Actinobacteria , Planctomycetacia , and Verrucomicrobiae present as well. Based on the parsimony test implemented in TreeClimber, libraries Rvi18 and Rvi24 were significantly different from Rve13 at the α = 0.05 level, while they were only borderline significantly different from each other ( p = 0.07). Differences between Rvi and Rve libraries were primarily due to differences in the number of Alphaproteobacteria sequences and specifically sequences from the Rhizobiales , which were more common in the Rve13 library. It is currently unknown what drives these differences between eubacterial communities. Amplification success for eubacterial 16S rDNA sequences was generally low in this study indicating low abundance of bacteria on tuberculate ECM. Attempts to amplify nitrogenase reductase ( nifH ) sequences were unsuccessful.
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isolation and characterization of microsatellite loci from the truffle like ectomycorrhizal fungi Rhizopogon occidentalis and Rhizopogon vulgaris
Molecular Ecology Notes, 2005Co-Authors: Lisa C Grubisha, Annette M Kretzer, Thomas D BrunsAbstract:We have isolated and characterized five microsatellite loci from Rhizopogon occidentalis and six loci from Rhizopogon vulgaris (Boletales, Basidiomycota). Microsatellite variation was assessed using 32 R. occidentalis and 48 R. vulgaris individuals from four populations in California. The number of alleles across populations ranged from two to 10 for R. occidentalis and three to eight for R. vulgaris . Expected heterozygosity values within populations ranged from 0.00 to 0.85 for R. occidentalis and 0.00 to 0.75 for R. vulgaris . These are the first microsatellite loci isolated for R. occidentalis and R. vulgaris and will be useful in the examination of their population genetic structure.
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patterns of vegetative growth and gene flow in Rhizopogon vinicolor and r vesiculosus boletales basidiomycota
Molecular Ecology, 2005Co-Authors: Annette M Kretzer, Randy Molina, Susie M Dunham, Joseph W SpataforaAbstract:We have collected sporocarps and tuberculate ectomycorrhizae of both Rhizopogon vinicolor and Rhizopogon vesiculosus from three 50 × 100 m plots located at Mary’s Peak in the Oregon Coast Range (USA); linear map distances between plots ranged from c . 1 km to c . 5.5 km. Six and seven previously developed microsatellite markers were used to map the approximate size and distribution of R. vinicolor and R. vesiculosus genets, respectively. Genetic structure within plots was analysed using spatial autocorrelation analyses. No significant clustering of similar genotypes was detected in either species when redundant samples from the same genets were culled from the data sets. In contrast, strong clustering was detected in R. vesiculosus when all samples were analysed, but not in R. vinicolor . These results demonstrate that isolation by distance does not occur in either species at the intraplot sampling scale and that clonal propagation (vegetative growth) is significantly more prevalent in R. vesiculosus than in R. vinicolor . Significant genetic differentiation was detected between some of the plots and appeared greater in the more clonal species R. vesiculosus with Φ Φ Φ ST values ranging from 0.010 to 0.078*** than in R. vinicolor with Φ ST values ranging from − − − 0.002 to 0.022** (* P < 0.05, ** P < 0.01, *** P < 0.001). When tested against the null hypothesis of no relationship between individuals, parentage analysis detected seven likely parent/offspring pairs in R. vinicolor and four in R. vesiculosus (α α α = 0.001). Of these 11 possible parent/offspring pairs, only two R. vinicolor pairs were still supported as parent/offspring when tested against the alternative hypothesis of being full siblings (α = 0.05). In the latter two cases, parent and offspring were located at approximately 45 m and 28 m from each other. Challenges to parentage analysis in ectomycorrhizal fungi are discussed.
Daniel M Durall - One of the best experts on this subject based on the ideXlab platform.
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dominance of a Rhizopogon sister species corresponds to forest age structure
Mycorrhiza, 2016Co-Authors: Carrie H. Van Dorp, Kevin J Beiler, Daniel M DurallAbstract:Rhizopogon vesiculosus and Rhizopogon vinicolor are sister species of ectomycorrhizal fungi that associate exclusively with Douglas-fir (DF). They form tuberculate mycorrhizas and they can be easily distinguished using molecular tools. We are not aware of studies relating their relative abundance in forests with different age classes. Our objective was to determine whether a change in the number or relative abundance of R. vesiculosus and R. vinicolor tubercules and genotypes was related to a change in the percent of DF in a regenerating phase (<50 years old). R. vesiculosus and R. vinicolor were located by excavating tuberculate mycorrhizas from the forest floor. A DNA Alu1 digest was used to distinguish between the two species. Microsatellite markers were used to identify genotypes. The number of R. vesiculosus tubercules correlated positively with an increasing proportion of DF in a regenerating phase, while the number of R. vinicolor tubercules was similar across all forest age structures. The number of R. vesiculosus genotypes did not correlate with forest age structure, whereas the number of R. vinicolor genotypes showed a negative relationship with an increasing proportion of DF in a regenerating phase. When the numbers of R. vesiculosus tubercules and genotypes were expressed as a relative abundance of the two species, there was a positive correlation with an increasing proportion of DF in a regenerating phase for both genotypes and tubercules. Our results suggest that the degree of DF regeneration or ecosystem factors related to DF regeneration affect the population dynamics of R. vesiculosus and R. vinicolor differently.
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Dominance of a Rhizopogon sister species corresponds to forest age structure
Mycorrhiza, 2015Co-Authors: Carrie H. Van Dorp, Kevin J Beiler, Daniel M DurallAbstract:Rhizopogon vesiculosus and Rhizopogon vinicolor are sister species of ectomycorrhizal fungi that associate exclusively with Douglas-fir (DF). They form tuberculate mycorrhizas and they can be easily distinguished using molecular tools. We are not aware of studies relating their relative abundance in forests with different age classes. Our objective was to determine whether a change in the number or relative abundance of R. vesiculosus and R. vinicolor tubercules and genotypes was related to a change in the percent of DF in a regenerating phase (
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vertical partitioning between sister species of Rhizopogon fungi on mesic and xeric sites in an interior douglas fir forest
Molecular Ecology, 2012Co-Authors: Kevin J Beiler, Suzanne W Simard, Valerie Lemay, Daniel M DurallAbstract:Understanding ectomycorrhizal fungal (EMF) community structure is limited by a lack of taxonomic resolution and autecological information. Rhizopogon vesiculosus and Rhizopogon vinicolor (Basidiomycota) are morphologically and genetically related species. They are dominant members of interior Douglas-fir (Pseudotsuga menziesii var. glauca) EMF communities, but mechanisms leading to their coexistence are unknown. We investigated the microsite associations and foraging strategy of individual R. vesiculosus and R. vinicolor genets. Mycelia spatial patterns, pervasiveness and root colonization patterns of fungal genets were compared between Rhizopogon species and between xeric and mesic soil moisture regimes. Rhizopogon spp. mycelia were systematically excavated from the soil and identified using microsatellite DNA markers. Rhizopogon vesiculosus mycelia occurred at greater depth, were more spatially pervasive, and colonized more tree roots than R. vinicolor mycelia. Both species were frequently encountered in organic layers and between the interface of organic and mineral horizons. They were particularly abundant within microsites associated with soil moisture retention. The occurrence of R. vesiculosus shifted in the presence of R. vinicolor towards mineral soil horizons, where R. vinicolor was mostly absent. This suggests that competition and foraging strategy may contribute towards the vertical partitioning observed between these species. Rhizopogon vesiculosus and R. vinicolor mycelia systems occurred at greater mean depths and were more pervasive in mesic plots compared with xeric plots. The spatial continuity and number of trees colonized by genets of each species did not significantly differ between soil moisture regimes.
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Vertical partitioning between sister species of Rhizopogon fungi on mesic and xeric sites in an interior Douglas‐fir forest
Molecular Ecology, 2012Co-Authors: Kevin J Beiler, Suzanne W Simard, Valerie Lemay, Daniel M DurallAbstract:Understanding ectomycorrhizal fungal (EMF) community structure is limited by a lack of taxonomic resolution and autecological information. Rhizopogon vesiculosus and Rhizopogon vinicolor (Basidiomycota) are morphologically and genetically related species. They are dominant members of interior Douglas-fir (Pseudotsuga menziesii var. glauca) EMF communities, but mechanisms leading to their coexistence are unknown. We investigated the microsite associations and foraging strategy of individual R. vesiculosus and R. vinicolor genets. Mycelia spatial patterns, pervasiveness and root colonization patterns of fungal genets were compared between Rhizopogon species and between xeric and mesic soil moisture regimes. Rhizopogon spp. mycelia were systematically excavated from the soil and identified using microsatellite DNA markers. Rhizopogon vesiculosus mycelia occurred at greater depth, were more spatially pervasive, and colonized more tree roots than R. vinicolor mycelia. Both species were frequently encountered in organic layers and between the interface of organic and mineral horizons. They were particularly abundant within microsites associated with soil moisture retention. The occurrence of R. vesiculosus shifted in the presence of R. vinicolor towards mineral soil horizons, where R. vinicolor was mostly absent. This suggests that competition and foraging strategy may contribute towards the vertical partitioning observed between these species. Rhizopogon vesiculosus and R. vinicolor mycelia systems occurred at greater mean depths and were more pervasive in mesic plots compared with xeric plots. The spatial continuity and number of trees colonized by genets of each species did not significantly differ between soil moisture regimes.
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rediscovery of the vesicles that characterized Rhizopogon vesiculosus
Mycologia, 2011Co-Authors: Daniel L Luoma, Daniel M Durall, Joyce L Eberhart, Kate SidlarAbstract:Molecular distinction between Rhizopogon vinicolor and R. vesiculosus has been made recently, but the diagnostic ''yellow-brown (fresh) inflated cells'' of R. vesiculosus, originally described by AH Smith, were not observed. These distinctive hyphal cells (vesicles) have not been reported since the type description. In that description they were said to collapse upon drying and described as being difficult to find. Here we report the rediscovery of these vesicles and describe their specific location on sporocarps of R. vesiculosus .W e also report an original discovery that coiled, dark-walled hyphae on the sporocarps and in the mycorrhizae of R. vinicolor are of taxonomic value. The coiled hyphae, combined with the presence or absence of the elusive vesicles, allow R. vesiculosus and R. vinicolor to be morpho- logically distinguished with increased accuracy.
