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1.
Life (Basel) ; 11(6)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34204923

RESUMO

Wildfires play a critical role in maintaining biodiversity and shaping ecosystem structure in fire-prone regions, and successional patterns involving numerous plant and fungal species in post-fire events have been elucidated. Evidence is growing to support the idea that some post-fire fungi can form endophytic/endolichenic relationships with plants and lichens. However, no direct observations of fire-associated fungal-moss interactions have been visualized to date. Therefore, physical interactions between a post-fire fungus, Pholiota carbonaria, and a moss, Polytrichum commune, were visually examined under laboratory conditions. Fungal appressoria were visualized on germinating spores and living protonemata within two weeks of inoculation in most growth chambers. Appressoria were pigmented, reddish gold to braun, and with a penetration peg. Pigmented, reddish gold to braun fungal hyphae were associated with living tissue, and numerous mature rhizoids contained fungal hyphae at six months. Inter-rhizoidal hyphae were pigmented and reddish gold to braun, but no structures were visualized on mature gametophyte leaf or stem tissues. Based on our visual evidence and previous work, we provide additional support for P. carbonaria having multiple strategies in how it obtains nutrients from the environment, and provide the first visual documentation of these structures in vitro.

2.
Mycologia ; 112(4): 677-698, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497465

RESUMO

Following a late fall wildfire in 2016 in the Great Smoky Mountains National Park, pyrophilous fungi in burn zones were documented over a 2-y period with respect to burn severity and phenology. Nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) barcodes were obtained to confirm morphological evaluations. Forty-one taxa of Ascomycota and Basidiomycota were identified from burn sites and categorized as fruiting only in response to fire or fruiting enhanced by fire. Twenty-two species of Pezizales (Ascomycota) were among the earliest to form ascomata in severe burn zones, only one of which had previously been documented in the Great Smoky Mountains National Park. Nineteen species of Basidiomycota, primarily Agaricales, were also documented. Among these, only five species (Coprinellus angulatus, Gymnopilus decipiens, Lyophyllum anthracophilum, Pholiota carbonicola, and Psathyrella pennata) were considered to be obligate pyrophilous taxa, but fruiting of two additional taxa (Hygrocybe conica and Mycena galericulata) was clearly enhanced by fire. Laccaria trichodermophora was an early colonizer of severe burn sites and persisted through the winter of 2017 and into spring and summer of 2018, often appearing in close association with Pinus pungens seedlings. Fruiting of pyrophilous fungi peaked 4-6 mo post fire then diminished, but some continued to fruit up to 2.5 y after the fire. In all, a total of 27 previously unrecorded taxa were added to the All Taxa Biodiversity Inventory (ATBI) database (~0.9%). Most pyrophilous fungi identified in this study are either cosmopolitan or have a Northern Hemisphere distribution, but cryptic endemic lineages were detected in Anthracobia and Sphaerosporella. One new combination, Hygrocybe spadicea var. spadicea f. odora, is proposed.


Assuntos
Biodiversidade , Fungos/crescimento & desenvolvimento , Parques Recreativos , Incêndios Florestais , DNA Fúngico/genética , DNA Ribossômico/genética , Carpóforos/classificação , Carpóforos/genética , Carpóforos/crescimento & desenvolvimento , Fungos/classificação , Fungos/genética , Filogenia , Pinus/microbiologia , Estados Unidos
3.
Am J Bot ; 107(6): 876-885, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32496601

RESUMO

PREMISE: Pyrophilous fungi form aboveground fruiting structures (ascocarps) following wildfires, but their ecology, natural history, and life cycles in the absence of wildfires are largely unknown. Sphaerosporella is considered to be pyrophilous. This study explores Sphaerosporella ascocarp appearance following a rare 2016 wildfire in the Great Smoky Mountains National Park (GSMNP), compares the timing of ascocarp formation with recovery of Sphaerosporella DNA sequences in soils, and explores the association of Sphaerosporella with post-fire Table Mountain pine (Pinus pungens) seedlings. METHODS: Burned sites in the GSMNP were surveyed for pyrophilous fungal ascocarps over 2 years. Ascocarps, mycorrhizae, and endophyte cultures were evaluated morphologically and by Sanger sequencing of the nuclear ribosomal ITS gene region (fungal barcode; Schoch et al., 2012). DNA from soil cores was subjected to Illumina sequencing. RESULTS: The timing and location of post-fire Sphaerosporella ascocarp formation was correlated with recovery of Sphaerosporella DNA sequences in soils. Genetic markers (fungal barcode) of Sphaerosporella were also recovered from mycorrhizal root tips and endophyte cultures from seedlings of Pinus pungens. CONCLUSIONS: This study demonstrates that Sphaerosporella species, in the absence of fire, are biotrophic, forming both mycorrhizal and endophytic associations with developing Pinus pungens seedlings and may persist in nature in the absence of wildfire as a conifer symbiont. We speculate that Sphaerosporella may fruit only after the host plant is damaged or destroyed and that after wildfires, deep roots, needle endophytes, or heat-resistant spores could serve as a source of soil mycelium.


Assuntos
Micorrizas , Pinus , Fungos , Estilo de Vida , Raízes de Plantas , Plântula
4.
Mycologia ; 110(6): 1205-1221, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30513277

RESUMO

Morphological and molecular phylogenetic studies of true morels (Morchella) in North America, the Dominican Republic, Venezuela, Ecuador, and Peru led to the discovery of four undescribed species of Morchella. Two new species in the Elata clade, one from the Dominican Republic, initially distinguished by the informal designation Mel-18, and a newly discovered sister species from northern Arizona, are now recognized. Mel-18 is described as a novel phylogenetically distinct species, M. hispaniolensis. Its sister species from Arizona is described as M. kaibabensis, also recovered as an endophyte of Rocky Mountain juniper. Two additional species in the Esculenta clade, M. peruviana discovered in Peru and M. gracilis (previously reported as Mes-14) from the Dominican Republic, Venezuela, and Ecuador, are described as new. We also demonstrate that scanning electron microscopy (SEM) imaging of ascospores using rehydration/dehydration/critical point drying preparation techniques provides for enhanced resolution of spore wall surfaces, thereby increasing the number of morphological traits available to assess differences among otherwise closely related species.


Assuntos
Ascomicetos/classificação , Filogenia , América , Arizona , Ascomicetos/isolamento & purificação , DNA Fúngico/genética , DNA Ribossômico/genética , Equador , Microscopia Eletrônica de Varredura , Técnicas de Tipagem Micológica , Peru , Fenótipo , Análise de Sequência de DNA , Esporos Fúngicos/ultraestrutura , Venezuela
5.
Mycologia ; 109(3): 529-534, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28841369

RESUMO

"With poetry, the tune is in the words themselves-and once you begin to hear it, it will stay with you." Richard P. Korf, notes to his narration of John Brown's Body.

6.
Mycologia ; 109(6): 900-911, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29537942

RESUMO

Bulgariella pulla (Leotiomycetes) is redescribed with the addition of characters of the ascus, spores, and habitat that were previously unconsidered. The ascus dehiscence mechanism in Bulgariella is unusual among Leotiomycetes. In this genus, asci lack a pore and open by splitting to form valves. Phylogenetic analyses of partial sequences of translation elongation factor 1-α (TEF1-α), the second largest subunit of RNA polymerase II (RPB2), and the 18S and 28S nuc rRNA genes determined that Bulgariella belongs within Leotiomycetes but without conclusive assignment to an order or family. A comparison of the nuc rDNA internal transcribed spacers 1 and 2 plus the 5.8S gene (ITS) determined that Bulgariella isolates from the USA, Norway, and Sweden had 100% sequence similarity, and an isolate from Chile had 99.3% similarity with these isolates. These results support the proposition that these collections represent a single species, B. pulla. Bulgariella sphaerospora, a more recently described species, is confirmed as conspecific with B. pulla.


Assuntos
Ascomicetos/classificação , Ascomicetos/citologia , América , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Europa (Continente) , Microscopia , Fator 1 de Elongação de Peptídeos/genética , Filogenia , RNA Polimerase II/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Esporos Fúngicos/citologia
7.
Mycologia ; 109(5): 710-714, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29370582

RESUMO

Reports of true morels (Morchella) fruiting on conifer burn sites are common in western North America where five different fire-adapted species of black morels (Elata Clade) have been documented based on multilocus phylogenetic analyses. Fruiting of post-fire morels in eastern North America, by comparison, are rare and limited to a report from Minnesota in 1977 and eastern Ontario in 1991. Here, nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) sequences were used to identify the post-fire morel that fruited in great abundance the year following the 2012 Duck Lake Fire in the Upper Peninsula of Michigan and after the 2016 large-scale fire in the Great Smoky Mountains National Park in Tennessee as M. exuberans. A preliminary phylogenetic analysis suggests that the collections from eastern North America may be more closely related to those from Europe than from western North America, Europe, and China.


Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Incêndios , Ascomicetos/genética , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Michigan , Filogenia , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Tennessee
8.
Mycologia ; 100(3): 392-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18751547

RESUMO

'Sporidesmium' lichenicola sp. nov. is described from the decaying thallus of an unidentified Leptogium species growing on unidentified tree bark from the Guaramacal National Park in Boconó, Táchira, in western Venezuela. This is only the second lichenicolous species to be described under this generic name, and differences from that species and similar species in Sporidesmium s. lat. are discussed. A more precise generic placement will have to await a molecularly based taxonomy of the genus. The original material comes from a mycologically little explored region of the country, and brief information on previous mycological (including lichenological) studies in the area is provided for the first time in English. The new combination S. sinense (syn. Repetophragma sinense) also is made.


Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Ascomicetos/citologia , Plantas/microbiologia , Venezuela
10.
Rev Iberoam Micol ; 22(2): 71-82, 2005 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-16107164

RESUMO

Lichens have value as bioindicators of environmental pollution, climate change, and ecological continuity. Extensive work has been undertaken in temperate areas, but in only few cases have the techniques been applied in the tropics. Most tropical studies to date are in relation to air pollution and forest disturbance, but these are scattered geographically and remain to be undertaken in most tropical regions. The potential of lichens as rapid bioindicators in the tropics can start to be realized even where the species described are not fully identified as they are perennial and separable by eye or hand lens, and a lack of training is identified as the main constraint. An extensive bibliography is included.


Assuntos
Meio Ambiente , Monitoramento Ambiental/métodos , Poluição Ambiental , Líquens , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/farmacologia , Biodiversidade , Conservação dos Recursos Naturais , Hong Kong , Líquens/efeitos dos fármacos , Líquens/crescimento & desenvolvimento , Líquens/efeitos da radiação , Líquens/ultraestrutura , Metais Pesados/análise , Metais Pesados/farmacologia , Poluentes Radioativos/análise , Poluentes Radioativos/farmacologia , Poluentes do Solo/análise , Poluentes do Solo/farmacologia , América do Sul , Dióxido de Enxofre/análise , Dióxido de Enxofre/farmacologia , Tailândia , Clima Tropical , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/farmacologia
11.
Mycologia ; 96(4): 925-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-21148912

RESUMO

Skyttea richardsonii sp. nov. is described from a sterile corticolous lichen in Maine. It is closest to S. tavaresae, the only other member of the genus to be reported as having annelations on the excipular hairs, but that species occurs on Loxospora spp. and differs in the K+ reaction of the exciple and ascospore size. Minute Phoma-like conidiomata found in some apothecia may represent an independent fungicolous fungus growing on the new species. This is the 10th species of the genus to have been discovered in North America; a key to these species is provided.

12.
Mycologia ; 96(5): 1155-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-21148935

RESUMO

Korfiomyces gelatinosum gen. et sp. nov. is described from resinous wood of an unidentified tree in the Venezuelan Amazon, part of the Guayana region; it is saprobic and not lichenized. The ascomata are apothecioid, arise on a brownish subiculum, are gelatinous and initially have a raised exciple. The asci are lecanoralean with a thin outer amyloid layer and occasionally a minute internal apical amyloid ring. The paraphyses are simple and capitate, and the as-cospores brownish and 1-septate. The possible affinities of the new genus are discussed; no family to accommodate it satisfactorily was found, and for the time being it is recommended that it be treated as Lecanoromycetes incertae sedis.

13.
Mycologia ; 95(6): 1066-77, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-21149014

RESUMO

Antrodiella dentipora, Ceriporia albobrunnea, C. cystidiata, Diplomitoporus allantosporus, D. stramineus, D. venezuelicus, Flabellophora fasciculata, Navisporus perennis, Nigroporus macroporus, Polyporus albostipes, Rigidoporus aurantiacus, Skeletocutis microcarpa, Tinctoporellus isabellinus, Trametes olivaceopora, T. supermodesta, Trichaptum variabilis, Tyromyces neostrigosus, T. polyporoides and Wrightoporia roseocontexta are described as new. Keys to all, except Trametes, the new neotropical species in their respective genera are included. The combinations Trichaptum griseofuscens (Mont.) Ryvarden & Iturriaga, and Tyromyces americanus (D. Reid) Ryvarden & Iturriaga are proposed.

14.
Med Mycol ; 40(3): 225-42, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12146752

RESUMO

Paracoccidioides brasiliensis is an amenable model to study the molecular and biochemical events that lead to morphological transition in fungi, because temperature seems to be the only factor regulating this process. It is the causative agent of paracoccidioidomycosis, a systemic mycosis that affects humans and that is geographically confined to Latin America, where it constitutes one of the most prevalent deep mycoses. With the help of molecular tools, events leading to the morphological transition have been traced to genes that control cell wall glucan and chitin syntheses, and other metabolic processes such as production of heat shock proteins and ornithine decarboxylase activity. Molecular diagnosis and epidemiology of paracoccidioidomycosis are also the focus of intensive research, with several primers being proposed as specific probes for clinical and field uses. Although P. brasiliensis is refractory to cytogenetic analysis, electrophoretic methods have allowed an approximation of its genomic organization and ploidy. Finally, the recognition of P. brasiliensis as an anamorph in the phylum Ascomycota, order Onygenales, family Onygenaceae, has been accomplished by means of molecular tools. This phylogenetic placement has revised the taxonomic position of this fungus, which was traditionally included within now-abandoned higher anamorph taxa, the phylum Deuteromycota and the class Hyphomycetes.


Assuntos
Paracoccidioides/crescimento & desenvolvimento , Paracoccidioidomicose/diagnóstico , Parede Celular/química , Parede Celular/genética , Quitina/biossíntese , Quitina/genética , DNA Fúngico/genética , Microbiologia Ambiental , Genes Fúngicos , Glucanos/biossíntese , Glucanos/genética , Proteínas de Choque Térmico/biossíntese , Proteínas de Choque Térmico/genética , Humanos , América Latina/epidemiologia , Morfogênese , Ornitina Descarboxilase/genética , Ornitina Descarboxilase/metabolismo , Paracoccidioides/classificação , Paracoccidioides/genética , Paracoccidioidomicose/epidemiologia , Filogenia , Ploidias , Polimorfismo Genético , Especificidade da Espécie
15.
Mycologia ; 94(4): 673-82, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-21156540

RESUMO

Cookeina, with seven recognized species, is one of the commonly encountered genera of the Sarcoscyphaceae (Pezizales) in tropical and subtropical areas around the world. Morphologically the species are distinguished by combinations of several features including ascospore shape and surface relief, presence and origin of apothecial hairs and presence or absence of gelatinous material within the cortical layer of the excipular tissue. Color of the hymenium, attributed to carotenoid pigments, is particularly variable in some collections especially those referred to as C. speciosa. In this study phylogenetic analyses were carried out using rDNA ITS and rDNA LSU sequences. Forty-four collections were studied which included a broad sampling of color variants of C. speciosa from a field site in Venezuela. The genus was shown to be monophyletic with several well-supported lineages. These analyses generally support the established, morphologically distinguished taxa within a monophyletic genus Cookeina. Collections referred to as C. speciosa segregate within a clade in which hymenial color differences are associated with groups within the clade. Cookeina sinensis is sister to C. tricholoma but is distinct from it; C. indica fails to resolve with any of the major clades. The placement of C. insititia is ambiguous but it falls within Cookeina and thus is considered in the genus Cookeina rather than in a separate genus, Boedijnopeziza.

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