Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Mycologia ; 110(5): 890-918, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30215579

RESUMO

In this study, 49 species of Hydnum are recognized worldwide. Twenty-two of them are described here as new species. Epitypes are proposed for H. repandum and H. rufescens. The majority of the species are currently known only from a single continent. The barcodes produced in this study are deposited in the RefSeq database and used as a basis to name species hypotheses in UNITE. Eleven infrageneric clades recovered in a phylogenetic analysis are supported by morphological characteristics and formally recognized: subgenera Alba, Hydnum, Pallida, and Rufescentia; sections Hydnum, Olympica, Magnorufescentia, and Rufescentia; and subsections Mulsicoloria, Rufescentia, and Tenuiformia.


Assuntos
Basidiomycota/classificação , Basidiomycota/isolamento & purificação , Carpóforos/crescimento & desenvolvimento , Basidiomycota/citologia , Basidiomycota/crescimento & desenvolvimento , Biometria , Código de Barras de DNA Taxonômico , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Europa (Continente) , Microscopia , América do Norte , Análise de Sequência de DNA , Esporos Fúngicos/citologia , Terminologia como Assunto
2.
Mycologia ; 109(3): 443-458, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28762885

RESUMO

Seven species of Cortinarius, subgenus Telamonia, section Colymbadini and /Flavobasilis, are reported from conifer forests in the mountains of western North America. They typically produce basidiomes in the spring and summer. Only one species, C. colymbadinus, is widespread, occurring in Europe and western North America, but to date not reported from California. Cortinarius bridgei, C. flavobasilis, C. rumoribrunsi, C. vernalishastensis, and C. vernalisierraensis are new species. The first two are found throughout the western mountains, whereas the latter three thus far are known only from California. Cortinarius ahsii, a common species in the Rocky Mountains and Pacific Northwest, also has not been recorded from California.


Assuntos
Cortinarius/classificação , Cortinarius/isolamento & purificação , Análise por Conglomerados , Cortinarius/citologia , Cortinarius/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Florestas , Microscopia , Noroeste dos Estados Unidos , Filogenia , Análise de Sequência de DNA , Traqueófitas/microbiologia
3.
Mycologia ; 108(5): 1018-1027, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27549620

RESUMO

Five species of Cortinarius subgenus Callistei, are recognized in Europe and North America. Cortinarius callisteus, C. infucatus, and C. neocallisteus sp. nov. have a broad distribution, extending from western North America to Europe. Cortinarius tofaceus is known from eastern North America and Europe, while C. callistei sp. is known only from one locality in Sweden. All five species are primarily associated with coniferous trees. Previously the species were included either in subgenus Leprocybe or subgenus Cortinarius, but recently they have been separated into subgenus Callistei based on molecular data. Type specimens of the names associated with this subgenus were studied and a neotype proposed for C. tofaceus and an epitype for C. infucatus Barcodes for the species are deposited in RefSeq and UNITE.


Assuntos
Biodiversidade , Cortinarius/citologia , Cortinarius/isolamento & purificação , América , Cortinarius/genética , Código de Barras de DNA Taxonômico , Europa (Continente) , América do Norte
4.
FEMS Microbiol Ecol ; 92(4): fiw045, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26929438

RESUMO

Different distance-based threshold selection approaches were used to assess and compare use of the internal transcribed spacer (ITS) region to distinguish among 901 Cortinarius species represented by >3000 collections. Sources of error associated with genetic markers and selection approaches were explored and evaluated using MOTUs from genus and lineage based-alignments. Our study indicates that 1%-2% more species can be distinguished by using the full-length ITS barcode as compared to either the ITS1 or ITS2 regions alone. Optimal threshold values for different picking approaches and genetic marker lengths inferred from a subset of species containing major lineages ranged from 97.0% to 99.5% sequence similarity using clustering optimization and UNITE SH, and from 1% to 2% sequence dissimilarity with CROP. Errors for the optimal cutoff ranged from 0% to 70%, and these can be reduced to a maximum of 22% when excluding species lacking a barcode gap. A threshold value of 99% is suitable for distinguishing species in the majority of lineages in the genus using the entire ITS region but only 90% of the species could be identified using just the ITS1 or ITS2 region. Prior identification of species, lacking barcode gaps and their subsequent separate analyses, maximized the accuracy of threshold approaches.


Assuntos
Cortinarius/classificação , Cortinarius/genética , Código de Barras de DNA Taxonômico/métodos , DNA Intergênico/genética , Micorrizas/genética , Marcadores Genéticos/genética , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA
5.
Mycologia ; 105(2): 344-56, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22962360

RESUMO

The North American species of Cortinarius section Sanguinei were studied using morphological characters and ITS and RPB2 sequence data. Several type collections also were examined. Four species were identified: C. harrisonii sp. nov, C. neosanguineus sp. nov., C. sanguineus and C. sierraensis comb. nov. Of these, C. sanguineus also occurs in Europe together with C. puniceus, a fifth member of the section. Typical features of these species include ± red, fairly small basidiomata, stipe basal mycelium often with yellow to reddish yellow tints, amygdaloid to ellipsoid spores, and aniline-red lamellar trama and pileipellis hyphae when mounted in KOH. Two other species with red lamellae C. marylandensis comb. nov. and C. smithii stat. nov. & nom. nov. also are discussed.


Assuntos
Cortinarius/classificação , Cortinarius/citologia , Cortinarius/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Carpóforos , Proteínas Fúngicas/genética , Micélio , América do Norte , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
6.
Mol Phylogenet Evol ; 57(3): 1276-92, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20970511

RESUMO

Porcini (Boletus section Boletus: Boletaceae: Boletineae: Boletales) are a conspicuous group of wild, edible mushrooms characterized by fleshy fruiting bodies with a poroid hymenophore that is "stuffed" with white hyphae when young. Their reported distribution is with ectomycorrhizal plants throughout the Northern Hemisphere. Little progress has been made on the systematics of this group using modern molecular phylogenetic tools because sampling has been limited primarily to European species and the genes employed were insufficient to resolve the phylogeny. We examined the evolutionary history of porcini by using a global geographic sampling of most known species, new discoveries from little explored areas, and multiple genes. We used 78 sequences from the fast-evolving nuclear internal transcribed spacers and are able to recognize 18 reciprocally monophyletic species. To address whether or not porcini form a monophyletic group, we compiled a broadly sampled dataset of 41 taxa, including other members of the Boletineae, and used separate and combined phylogenetic analysis of sequences from the nuclear large subunit ribosomal DNA, the largest subunit of RNA polymerase II, and the mitochondrial ATPase subunit six gene. Contrary to previous studies, our separate and combined phylogenetic analyses support the monophyly of porcini. We also report the discovery of two taxa that expand the known distribution of porcini to Australia and Thailand and have ancient phylogenetic connections to the rest of the group. A relaxed molecular clock analysis with these new taxa dates the origin of porcini to between 42 and 54 million years ago, coinciding with the initial diversification of angiosperms, during the Eocene epoch when the climate was warm and humid. These results reveal an unexpected diversity, distribution, and ancient origin of a group of commercially valuable mushrooms that may provide an economic incentive for conservation and support the hypothesis of a tropical origin of the ectomycorrhizal symbiosis.


Assuntos
Agaricales/classificação , Agaricales/genética , Evolução Molecular , Filogenia , Teorema de Bayes , DNA Fúngico/genética , DNA Mitocondrial/genética , DNA Espaçador Ribossômico/genética , Funções Verossimilhança , Alinhamento de Sequência , Análise de Sequência de DNA
7.
Clin Toxicol (Phila) ; 48(6): 545-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20615153

RESUMO

BACKGROUND: Some mushrooms in the genus Cortinarius are well known to cause acute and chronic renal failure. Until now, there have been no confirmed cases of renal failure due to the ingestion of a Cortinarius mushroom in North America. We describe a case of a woman who ingested mushrooms found under an oak tree in western Michigan and developed chronic renal failure. METHODS: Phylogenetic analysis of the internal transcribed spacer (ITS) regions of nuclear-encoded ribosomal RNA was performed between an unconsumed sample of the Michigan specimens, a control sample of Cortinarius orellanus (JFA9859) from Europe, and other closely related ITS sequences of Cortinarius retrieved from GenBank. An additional gene region, rpb2, was also sequenced for comparison. RESULTS: Phylogenetic analysis revealed the Michigan material to be closely related to, but distinct from, other ITS sequences of the Orellani clade in Cortinarius. Divergence is less at the rpb2 locus. No historical taxa from North America are known to match the identification of the Michigan material. CONCLUSION: The mushrooms ingested by the patient were confirmed to be a new species of Cortinarius closely related to C. orellanus. We introduce a newly described North American species, Cortinarius orellanosus, capable of causing renal failure after ingestion.


Assuntos
Cortinarius/patogenicidade , Falência Renal Crônica/etiologia , Intoxicação Alimentar por Cogumelos/complicações , Cortinarius/classificação , Cortinarius/genética , Feminino , Humanos , Michigan , Pessoa de Meia-Idade , Filogenia
8.
Mycologia ; 99(4): 569-85, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18065008

RESUMO

A taxonomic treatment of vinaceous and reddish species of Tubaria (Agaricales) is presented based on morphology and nucleotide sequences. Accessions from western North America, Europe, Central America, the Caribbean and Australia are compared. Phylogenetic analysis of the 25S rRNA gene and internal transcribed spacer (ITS) regions demonstrates that Tubaria is not monophyletic. However the autonomy of six brown-spored, saprotrophic species-Naucoria vinicolor, Pholiota serrulata, Phaeomarasmius confragosus, Pholiota punicea, Tubaria rufofulva and T. bispora sp. nov.-is affirmed. All six species form a strongly supported monophyletic group that we label section Confragosae in the genus Tubaria. This section is related to T. dispersa, T. albostipitata and numerous representatives of the T. furfuracea complex. Tubaria minima is related to other lineages of dark-spored Agaricales. Taxonomic descriptions, illustrations and a key to confirmed species of section Confragosae are provided. Four new combinations are proposed, and one new species, T. bispora, is described as new from Costa Rica and Martinique. A lectotype is designated for Pholiota serrulata.


Assuntos
Agaricales/classificação , Técnicas de Tipagem Micológica , Agaricales/genética , Agaricales/ultraestrutura , Teorema de Bayes , DNA Fúngico/análise , DNA Fúngico/isolamento & purificação , DNA Ribossômico/análise , DNA Espaçador Ribossômico , Dados de Sequência Molecular , Técnicas de Tipagem Micológica/métodos , Filogenia , RNA Ribossômico , Análise de Sequência de DNA , Especificidade da Espécie
9.
Mol Phylogenet Evol ; 43(2): 430-51, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17081773

RESUMO

A phylogeny of the fungal phylum Basidiomycota is presented based on a survey of 160 taxa and five nuclear genes. Two genes, rpb2, and tef1, are presented in detail. The rpb2 gene is more variable than tef1 and recovers well-supported clades at shallow and deep taxonomic levels. The tef1 gene recovers some deep and ordinal-level relationships but with greater branch support from nucleotides compared to amino acids. Intron placement is dynamic in tef1, often lineage-specific, and diagnostic for many clades. Introns are fewer in rpb2 and tend to be highly conserved by position. When both protein-coding loci are combined with sequences of nuclear ribosomal RNA genes, 18 inclusive clades of Basidiomycota are strongly supported by Bayesian posterior probabilities and 16 by parsimony bootstrapping. These numbers are greater than produced by single genes and combined ribosomal RNA gene regions. Combination of nrDNA with amino acid sequences, or exons with third codon positions removed, produces strong measures of support, particularly for deep internodes of Basidiomycota, which have been difficult to resolve with confidence using nrDNA data alone. This study produces strong boostrap support and significant posterior probabilities for the first time for the following monophyletic groups: (1) Ustilaginomycetes plus Hymenomycetes, (2) an inclusive cluster of hymenochaetoid, corticioid, polyporoid, Thelephorales, russuloid, athelioid, Boletales, and euagarics clades, (3) Thelephorales plus the polyporoid clade, (4) the polyporoid clade, and (5) the cantharelloid clade. Strong support is also recovered for the basal position of the Dacrymycetales in the Hymenomycetidae and paraphyly of the Exobasidiomycetidae.


Assuntos
Basidiomycota/classificação , Proteínas Fúngicas/genética , Fator 1 de Elongação de Peptídeos/genética , Filogenia , RNA Polimerase II/genética , Alelos , Sequência de Aminoácidos , Basidiomycota/genética , DNA Fúngico/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , Polimorfismo Genético , Pseudogenes , Spliceossomos
10.
Mycologia ; 98(6): 982-95, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17486974

RESUMO

An overview of the phylogeny of the Agaricales is presented based on a multilocus analysis of a six-gene region supermatrix. Bayesian analyses of 5611 nucleotide characters of rpb1, rpb1-intron 2, rpb2 and 18S, 25S, and 5.8S ribosomal RNA genes recovered six major clades, which are recognized informally and labeled the Agaricoid, Tricholomatoid, Marasmioid, Pluteoid, Hygrophoroid and Plicaturopsidoid clades. Each clade is discussed in terms of key morphological and ecological traits. At least 11 origins of the ectomycorrhizal habit appear to have evolved in the Agaricales, with possibly as many as nine origins in the Agaricoid plus Tricholomatoid clade alone. A family-based phylogenetic classification is sketched for the Agaricales, in which 30 families, four unplaced tribes and two informally named clades are recognized.


Assuntos
Agaricales/classificação , Agaricales/genética , Filogenia , Agaricales/fisiologia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ecologia , Íntrons/genética , ATPases Mitocondriais Próton-Translocadoras/genética , Dados de Sequência Molecular , Micorrizas , RNA Ribossômico/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Homologia de Sequência
11.
Mycologia ; 95(5): 836-45, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-21148991

RESUMO

The genetic diversity and phylogeny of Bridgeoporus nobilissimus have been analyzed. DNA was extracted from spores collected from individual fruiting bodies representing six geographically distinct populations in Oregon and Washington. Spore samples collected contained low levels of bacteria, yeast and a filamentous fungal species. Using taxon-specific PCR primers, it was possible to discriminate among rDNA from bacteria, yeast, a filamentous associate and B. nobilissimus. Nuclear rDNA internal transcribed spacer (ITS) region sequences of B. nobilissimus were compared among individuals representing six populations and were found to have less than 2% variation. These sequences also were used to design dual and nested PCR primers for B. nobilissimus-specific amplification. Mitochondrial small-subunit rDNA sequences were used in a phylogenetic analysis that placed B. nobilissimus in the hymenochaetoid clade, where it was associated with Oxyporus and Schizopora.

12.
Am J Bot ; 89(4): 688-98, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21665669

RESUMO

An investigation of mushroom phylogeny using the largest subunit of RNA polymerase II gene sequences (RPB1) was conducted in comparison with nuclear ribosomal large subunit RNA gene sequences (nLSU) for the same set of taxa in the genus Inocybe (Agaricales, Basidiomycota). The two data sets, though not significantly incongruent, exhibit conflict among the placement of two taxa that exhibit long branches in the nLSU data set. In contrast, RPB1 terminal branch lengths are rather uniform. Bootstrap support is increased for clades in RPB1. Combined data sets increase the degree of confidence for several relationships. Overall, nLSU data do not yield a robust phylogeny when independently assessed by RPB1 sequences. This multigene study indicates that Inocybe is a monophyletic group composed of at least four distinct lineages-subgenus Mallocybe, section Cervicolores, section Rimosae, and subgenus Inocybe sensu Kühner, Kuyper, non Singer. Within subgenus Inocybe, two additional lineages, one composed of species with smooth basidiospores (clade I) and a second characterized by nodulose-spored species (clade II), are recovered by RPB1 and combined data. The nLSU data recover only clade I. The genera Astrosporina and Inocybella cannot be recognized phylogenetically. "Supersections" Cortinatae and Marginatae are not monophyletic groups.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA