RESUMO
Powdery mildews are highly destructive fungal plant pathogens that have a significant economic impact on both agricultural and ecological systems worldwide. The intricate relationship between powdery mildews and their host plants has led to cospeciation. In this study, we conducted an extensive evaluation of powdery mildew hosts to provide an updated understanding of the host ranges and distributions of these fungi. The "United States National Fungus Collections Fungus-Host Dataset" is the primary source of information for our analyses. The analysis of the dataset demonstrated the worldwide prevalence of powdery mildews; the data contained over 72,000 reports of powdery mildews, representing â¼8.7% of all host-fungal records. We have updated the taxonomy and nomenclature of powdery mildews. In total, powdery mildews infect â¼10,125 host taxa belonging to 205 families of flowering plants, which accounts for 1,970 genera in 200 countries across six continents. Furthermore, we estimate that powdery mildews infect approximately 2.9% of described angiosperm species. Our study underscores the need for regular updates on powdery mildew host information due to the continuously evolving taxonomy and the discovery of new host taxa. Since 1986, we estimate an additional 1,866 host taxa, 353 genera, and 36 families have been reported. Additionally, the identification of powdery mildew hosts provides valuable insights into the coevolutionary dynamics between the fungi and their plant hosts. Overall, this updated list provides valuable insights into the taxonomy and geographic distribution of powdery mildew species, which builds upon the previous work of Amano in 1986. Discerning the geographic spread and host range of economically significant plant pathogens is vital for biosecurity measures and identifying the origins and expansion of potentially harmful pathogens.
Assuntos
Ascomicetos , Plantas , Erysiphe , Especificidade de HospedeiroRESUMO
Arthropod-fungus interactions involving the Laboulbeniomycetes have been pondered for several hundred years. Early studies of Laboulbeniomycetes faced several uncertainties. Were they parasitic worms, red algal relatives, or fungi? If they were fungi, to which group did they belong? What was the nature of their interactions with their arthropod hosts? The historical misperceptions resulted from the extraordinary morphological features of these oddly constructed ectoparasitic fungi. More recently, molecular phylogenetic studies, in combination with a better understanding of life histories, have clearly placed these fungi among filamentous Ascomycota (subphylum Pezizomycotina). Species discovery and research on the classification of the group continue today as arthropods, and especially insects, are routinely collected and examined for the presence of Laboulbeniomycetes. Newly armed with molecular methods, mycologists are poisedto use Laboulbeniomycetes-insect associations as models for the study of a variety of basic evolutionary and ecological questions involving host-parasite relationships, modes of nutrient intake, population biology, host specificity, biological control, and invasion biology. Collaboration between mycologists and entomologists is essential to successfully advance knowledge of Laboulbeniomycetes and their intimate association with their hosts.
Assuntos
Artrópodes/microbiologia , Ascomicetos/fisiologia , Interações Hospedeiro-Parasita , Animais , Ascomicetos/classificação , Micologia , FilogeniaRESUMO
The class Laboulbeniomycetes comprises biotrophic parasites associated with arthropods and fungi. Two orders are currently recognized, Pyxidiophorales and Laboulbeniales. Herpomyces is an isolated genus of Laboulbeniales, with species that exclusively parasitize cockroaches (Blattodea). Here, we evaluate 39 taxa of Laboulbeniomycetes with a three-locus phylogeny (nrSSU, ITS, nrLSU) and propose a new order in this class. Herpomycetales accommodates a single genus, Herpomyces, with currently 26 species, one of which is described here based on morphological and molecular data. Herpomyces shelfordellae is found on Shelfordella lateralis cockroaches from Hungary, Poland, and the USA. We also build on the six-locus dataset from the Ascomycota Tree of Life paper (Schoch and colleagues, 2009) to confirm that Laboulbeniomycetes and Sordariomycetes are sister classes, and we apply laboulbeniomyceta as a rankless taxon for the now well-resolved node that describes the most recent common ancestor of both classes.
Assuntos
Ascomicetos/classificação , Filogenia , Animais , Baratas/microbiologia , Hungria , Nucleotídeos/genética , Especificidade da EspécieRESUMO
"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.
RESUMO
A new species of Zodiomyces (Ascomycota, Laboulbeniales) is described, Z. rhizophorus, parasitic on a hydrophilid beetle (Coleoptera, Hydrophilidae) from Trinidad. This species was discovered during the examination of the slides of Laboulbeniales made by Roland Thaxter. It is characterized by numerous long, slender, multicellular and multiseriate outgrowths at the base of the receptacle. Thaxter's outstanding illustrations have set a standard in the field of mycology; we provide a review of the methods he employed in the preparation of these illustrations.
Assuntos
Ascomicetos/classificação , Ascomicetos/citologia , Animais , Ascomicetos/isolamento & purificação , Besouros/microbiologia , MicroscopiaRESUMO
During a study comparing the ectomycorrhizal root communities in a native forest with those at the Arnold Arboretum in Massachusetts (USA), the European species Tuber borchii was detected on the roots of a native red oak in the arboretum over two successive years. Since T. borchii is an economically important edible truffle native to Europe, we conducted a search of other roots in the arboretum to determine the extent of colonization. We also wanted to determine whether other non-native Tuber species had been inadvertently introduced into this 140-year-old Arboretum because many trees were imported into the site with intact soil and roots prior to the 1921 USDA ban on these horticultural practices in the USA. While T. borchii was not found on other trees, seven other native and exotic Tuber species were detected. Among the North American Tuber species detected from ectomycorrhizae, we also collected ascomata of a previously unknown species described here as Tuber arnoldianum. This new species was found colonizing both native and non-native tree roots. Other ectomycorrhizal taxa that were detected included basidiomycetes in the genera Amanita, Russula, Tomentella, and ascomycetes belonging to Pachyphlodes, Helvella, Genea, and Trichophaea. We clarify the phylogenetic relationships of each of the Tuber species detected in this study, and we discuss their distribution on both native and non-native host trees.
Assuntos
Ascomicetos/classificação , Ascomicetos/genética , Micorrizas/classificação , Raízes de Plantas/microbiologia , Quercus/microbiologia , Agricultura , Ascomicetos/fisiologia , DNA Fúngico/classificação , DNA Fúngico/genética , Massachusetts , Micorrizas/fisiologia , Filogenia , Microbiologia do Solo , Fatores de TempoRESUMO
Angelina rufescens is placed within the core clade of Rhytismatales (Leotiomycetes, Pezizomycotina, Ascomycota) based on analysis of LSU and mtSSU rDNA. The only species in the genus, it produces distinctive ascomata that reoccur annually on wood and on the remains of its own previous fructifications, forming dense conglomerations of interlocking longitudinally elongated apothecia with gray hymenia. Known collections and references of A. rufescens indicate that it is endemic to eastern and central United States. Morphological and cultural characters are described with notes on ascomata development. No mitospores were observed in field collections or in culture. Lectotypes are designated for Hysterium rufescens and its synonym Ascobolus conglomeratus. Angelina rufescens is illustrated here for the first time in the taxonomic literature.
Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Madeira/microbiologia , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Dados de Sequência Molecular , Filogenia , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificaçãoRESUMO
In this contribution, we offer the fifth installment of a series focusing on the phylogeny and taxonomy of powdery mildews. This paper is the second segment evaluating the genus Erysiphe. The first treatment of Erysiphe focused on phylogenetically basal species in the "Uncinula lineage." This research presents a phylogenetic-taxonomic assessment of species that form the group previously referred to as the "Microsphaera lineage." Given the size of the group, we split the treatment of this lineage of Erysiphe species into two parts based on their phylogenetic placement. Phylogenetic trees based on ITS+28S data are supplemented by sequences of additional markers (CAM, GADPH, GS, RPB2, and TUB). Included in the analysis of the Microsphaera lineage is the "Erysiphe aquilegiae complex" (group, clade, cluster), which encompasses sequences obtained from an assemblage of Erysiphe species with insufficient resolution in rDNA analyses. Attempts have been made to resolve this group at the species level by applying a multilocus approach. A detailed discussion of the "Erysiphe aquilegiae complex" is provided. Sequences are provided for the first time for several species, particularly North American species, such as Erysiphe aggregata, E. erineophila, E. parnassiae, and E. semitosta. Ex-type sequences for Microsphaera benzoin and M. magnusii have been retrieved. Alphitomorpha penicillata, Microsphaera vanbruntiana, and M. symphoricarpi are epitypified with ex-epitype sequences. The new species Erysiphe alnicola, E. deutziana, E. cornigena, E. lentaginis, and E. sambucina are described, the new combinations E. lauracearum, E. passiflorae, and E. sambucicola are introduced, and the new name E. santali is proposed.
Assuntos
Ascomicetos , Erysiphe , Filogenia , Erysiphe/genética , Doenças das Plantas , DNA Fúngico/genéticaRESUMO
Several members of the genus Peziza sensu stricto occur at the edge of melting snow. These nivicolous species have been widely reported in the Northern Hemisphere and are also known from Australia and New Zealand. We have used 16 specimens from North America and Australia to study morphology and to perform DNA sequencing. In sequence analyses, we have used ITS1 and ITS2 (internal transcribed spacers), 28S, RPB2 (RNA polymerase II gene), and two genes new to these studies, GAPDH (glyceraldehyde-3-phosphate dehydrogenase) and HSP90 (heat shock protein 90). Although not all regions are available for all samples, we have recognized the following species: Peziza heimii, P. nivalis, and P. nivis. Phylogenetic analyses were done using ITS alone; combined ITS1-5.8S-ITS2, 28S, and RPB2; ITS, and 28S, RPB2, GAPDH, and HSP90. Even with this augmented set of genes and despite their widespread occurrence in North America, Europe, Australia, and New Zealand, we have not definitively distinguished species within this group. To assess these results, pairwise homoplasy index (PHI) analysis was employed. This showed evidence of recombination among the samples of P. nivalis and further supports the view of P. nivalis as a monophyletic cosmopolitan species. As part of this study, we also examined the variation in ITS copies in P. echinospora, for which a genome is available.
RESUMO
Pyronemataceae is the largest and most heterogeneous family of Pezizomycetes. It is morphologically and ecologically highly diverse, comprising saprobic, ectomycorrhizal, bryosymbiotic and parasitic species, occurring in a broad range of habitats (on soil, burnt ground, debris, wood, dung and inside living bryophytes, plants and lichens). To assess the monophyly of Pyronemataceae and provide a phylogenetic hypothesis of the group, we compiled a four-gene dataset including one nuclear ribosomal and three protein-coding genes for 132 distinct Pezizomycetes species (4437 nucleotides with all markers available for 80% of the total 142 included taxa). This is the most comprehensive molecular phylogeny of Pyronemataceae, and Pezizomycetes, to date. Three hundred ninety-four new sequences were generated during this project, with the following numbers for each gene: RPB1 (124), RPB2 (99), EF-1α (120) and LSU rDNA (51). The dataset includes 93 unique species from 40 genera of Pyronemataceae, and 34 species from 25 genera representing an additional 12 families of the class. Parsimony, maximum likelihood and Bayesian analyses suggest that Pyronemataceae is paraphyletic due to the nesting of both Ascodesmidaceae and Glaziellaceae within the family. Four lineages with taxa currently classified in the family, the Boubovia, Geopyxis, Pseudombrophila and Pulvinula lineages, form a monophyletic group with Ascodesmidaceae and Glaziellaceae. We advocate the exclusion of these four lineages in order to recognize a monophyletic Pyronemataceae. The genus Coprotus (Thelebolales, Leotiomycetes) is shown to belong to Pezizomycetes, forming a strongly supported monophyletic group with Boubovia. Ten strongly supported lineages are identified within Pyronemataceae s. str. Of these, the Pyropyxis and Otidea lineages are identified as successive sister lineages to the rest of Pyronemataceae s. str. The highly reduced (gymnohymenial) Monascella is shown to belong to Pezizomycetes and is for the first time suggested to be closely related to the cleistothecial Warcupia, as a sister group to the primarily apothecial Otidea. None of the lineages of pyronemataceous taxa identified here correspond to previous families or subfamily classifications. Ancestral character state reconstructions (ASR) using a Bayesian approach support that the ancestors of Pezizomycetes and Pyronemataceae were soil inhabiting and saprobic. Ectomycorrhizae have arisen within both lineages A, B and C of Pezizomycetes and are suggested to have evolved independently seven to eight times within Pyronemataceae s. l., whereas an obligate bryosymbiotic lifestyle has arisen only twice. No reversals to a free-living, saprobic lifestyle have happened from symbiotic or parasitic Pyronemataceae. Specializations to various substrates (e.g. burnt ground and dung) are suggested to have occurred several times in mainly saprobic lineages. Although carotenoids in the apothecia are shown to have arisen at least four times in Pezizomycetes, the ancestor of Pyronemataceae s. str., excluding the Pyropyxis and Otidea lineages, most likely produced carotenoids, which were then subsequently lost in some clades (- and possibly gained again). Excipular hairs were found with a high probability to be absent from apothecia in the deepest nodes of Pezizomycetes and in the ancestor of Pyronemataceae s. str. True hairs are restricted to the core group of Pyronemataceae s. str., but are also found in Lasiobolus (Ascodesmidaceae), the Pseudombrophila lineage and the clade of Chorioactidaceae, Sarcoscyphaceae and Sarcosomataceae. The number of gains and losses of true hairs within Pyronemataceae s. str., however, remains uncertain. The ASR of ascospore guttulation under binary coding (present or absent) indicates that this character is fast evolving and prone to shifts.
Assuntos
Ascomicetos/genética , Evolução Molecular , Proteínas Fúngicas/genética , Filogenia , Teorema de Bayes , Carotenoides/genética , Núcleo Celular/genética , DNA Ribossômico/genética , Micorrizas/genética , Análise de Sequência de DNA , SimbioseRESUMO
This is the fourth contribution within an ongoing series dedicated to the phylogeny and taxonomy of powdery mildews. This particular installment undertakes a comprehensive evaluation of a group previously referred to as the "Uncinula lineage" within Erysiphe. The genus Erysiphe is too large to be assessed in a single paper; thus, the treatment of Erysiphe is split into three parts, according to phylogenetic lineages. The first paper, presented here, discusses the most basal lineage of Erysiphe and its relationship to allied basal genera within tribe Erysipheae (i.e., Brasiliomyces and Salmonomyces). ITS+28S analyses are insufficient to resolve the basal assemblage of taxa within the Erysipheae. Therefore, phylogenetic multilocus examinations have been carried out to better understand the evolution of these taxa. The results of our analyses favor maintaining Brasiliomyces, Bulbomicroidium, and Salmonomyces as separate genera, at least for the interim, until further phylogenetic multilocus data are available for additional basal taxa within the Erysipheae. The current analyses also confirmed previous results that showed that the "Uncinula lineage" is not exclusively composed of Erysiphe species of sect. Uncinula but also includes some species that morphologically align with sect. Erysiphe, as well as species that had previously been assigned to Californiomyces and Typhulochaeta. Numerous sequences of Erysiphe species from the "Uncinula lineage" have been included in the present phylogenetic analyses and were confirmed by their position in well-supported species clades. Several species have been sequenced for the first time, including Erysiphe clintonii, E. couchii, E. geniculata, E. macrospora, and E. parvula. Ex-type sequences are provided for 16 taxa including E. nothofagi, E. trinae, and E. variabilis. Epitypes are designated and ex-epitype sequences are added for 18 taxa including Erysiphe carpophila, E. densa, and U. geniculata var. carpinicola. The new species Erysiphe canariensis is described, and the new names E. hosagoudarii and E. pseudoprunastri and the new combination E. ampelopsidis are introduced.
Assuntos
Ascomicetos , Erysiphe , Filogenia , Doenças das Plantas , Ascomicetos/genéticaRESUMO
Tympanis species (Leotiales) are plant pathogens distributed mostly in northern temperate ecosystems. The diversity and identity of some species remains unclear. Tympanis vagabunda, found in Sicilia (Italy) on dry twigs of Rosa, Rubus, and Pistacia, is one example of an obscure and poorly known species. During the study of its type specimen in S, which contained one twig with a wood anatomy fitting neither of the three mentioned hosts, the microanatomic structures indicated that it belongs to the genus Rutstroemia (Helotiales). To investigate its identity, the types of R. fruticeti, R. juniperi, R. urceolus, and R. longiasca were studied for comparison. The species for which molecular data were available were included in a dataset that contained identified species of Rutstroemia, along with other select species from the families Rutstroemiaceae and Sclerotiniaceae. R. fruticeti, a saprobe frequently reported from Rubus fruticosus in Europe, is found to be a later synonym of T. vagabunda, and the combination Rutstroemia vagabunda is proposed. R. juniperi is an infrequently reported European species on twigs of Juniperus and is morphologically hard to distinguish from R. vagabunda; available molecular data support its recognition as a distinct species. R. longiasca differs from R. vagabunda in its black apothecia, smaller asci, and narrower ascospores. R. urceolus differs from R. vagabunda in having black apothecia and smaller inamyloid asci, and excipulum at the flanks and margin is composed of dark-walled hyphae.
RESUMO
This contribution is part of a series devoted to the phylogeny and taxonomy of powdery mildews, with an emphasis on North American taxa. An overview of Cystotheca species is given, including references to ex-type sequences or, if unavailable, proposals for representative reference sequences for phylogenetic-taxonomic purposes. The new species C. mexicana is described, based on Mexican collections on Quercus glaucoides × Quercus microphylla and Quercus liebmannii × Q. microphylla. Cystotheca lanestris is reported for the first time worldwide on Quercus laceyi (Collected in Mexico) and on Q. toumeyi (collected in Arizona, USA). Cystotheca lanestris on Q. agrifolia and on Q. cerris is reported for the first time in Mexico. Epitypes with ex-epitype sequences are designated for Cystotheca wrightii, Lanomyces tjibodensis (= C. tjibodensis), Sphaerotheca kusanoi, and S. lanestris (C. lanestris).
Assuntos
Quercus , Filogenia , México , ArizonaRESUMO
Spores are important as dispersal and survival propagules in fungi. In this study we investigated the variation in number, shape, size and germination mode of ascospores in Morchella galilaea, the only species of the genus Morchella known to fruit in the autumn. Based on the observation of five samples, we first discovered significant variation in the shape and size of ascospores in Morchella. One to sixteen ascospores were found in the asci. Ascospore size correlated negatively with ascospore number, but positively with ascus size, and ascus size was positively correlated with ascospore number. We noted that ascospores, both from fresh collections and dried specimens, germinated terminally or laterally either by extended germ tubes, or via the production of conidia that were formed directly from ascospores at one, two or multiple sites. The direct formation of conidia from ascospores takes place within asci or after ascospores are discharged. Using laser confocal microscopy, we recorded the number of nuclei in ascospores and in conidia produced from ascospores. In most ascospores of M. galilaea, several nuclei were observed, as is typical of species of Morchella. However, nuclear number varied from zero to around 20 in this species, and larger ascospores harbored more nuclei. One to six nuclei were present in the conidia. Nuclear migration from ascospores to conidia was observed. Conidia forming directly from ascospores has been observed in few species of Pezizomycetes; this is the first report of the phenomenon in Morchella species. Morphological and molecular data show that conidial formation from ascospores is not found in all the specimens of this species and, hence, is not an informative taxonomic character in M. galilaea. Our data suggest that conidia produced from ascospores and successive mitosis within the ascus may contribute to asci with more than eight spores. The absence of mitosis and/or nuclear degeneration, as well as cytokinesis defect, likely results in asci with fewer than eight ascospores. This study provides new insights into the poorly understood life cycle of Morchella species and more broadly improves knowledge of conidia formation and reproductive strategies in Pezizomycetes.
RESUMO
Fungi are among the most biodiverse organisms in the world. Accurate species identification is imperative for studies on fungal ecology and evolution. The internal transcribed spacer (ITS) rDNA region has been widely accepted as the universal barcode for fungi. However, several recent studies have uncovered intragenomic sequence variation within the ITS in multiple fungal species. Here, we mined the genome of 2414 fungal species to determine the prevalence of intragenomic variation and found that the genomes of 641 species, about one-quarter of the 2414 species examined, contained multiple ITS copies. Of those 641 species, 419 (â¼65%) contained variation among copies revealing that intragenomic variation is common in fungi. We proceeded to show how these copies could result in the erroneous description of hundreds of fungal species and skew studies evaluating environmental DNA (eDNA) especially when making diversity estimates. Additionally, many genomes were found to be contaminated, especially those of unculturable fungi.
RESUMO
Powdery mildews are a monophyletic group of obligate plant pathogenic fungi in the family Erysiphaceae. Powdery mildews are economically important in that they cause damage to many agriculturally significant crops and plants in ecologically important habitats. In this contribution, we introduce a new series of publications focusing on the phylogeny and taxonomy of this group, with an emphasis on specimens collected from North America. The first part of the series focuses on the genus Golovinomyces and includes a section detailing the powdery mildew species concept. We conducted analyses of Golovinomyces spp. with available rDNA sequence data from GenBank and supplemented the data set with rDNA (ITS, 28S, IGS) as well as protein-coding (GAPDH) data from 94 North American collections. Many of the species evaluated are included in phylogenetic and morphological analyses for the first time, including the American species G. americanus, G. brunneopunctatus, G. californicus, G. greeneanus, G. hydrophyllacearum, and G. sparsus. A special emphasis was placed on acquiring ex-type or ex-epitype sequences or presenting reference sequences for phylogenetic-taxonomic purposes. Three new species, G. eurybiarum, G. galiorum, and G. malvacearum, are described, and the new combinations G. fuegianus, G. mutisiae, and G. reginae are introduced. Ex-holotype sequences of Erysiphe sparsa (≡ G. sparsus) reveal that it should be reduced to synonymy with G. ambrosiae, and ex-epitype sequences of G. valerianae reveal that it should be reduced to synonymy with G. orontii. Multiple epitypes are designated with ex-epitype sequences.
Assuntos
Ascomicetos , Doenças das Plantas , Filogenia , Doenças das Plantas/microbiologia , DNA Fúngico/genética , Ascomicetos/genética , DNA Ribossômico/genética , Plantas/microbiologiaRESUMO
The second contribution to a new series devoted to the phylogeny and taxonomy of powdery mildews is presented. An overview of Neoerysiphe species is given, including references to ex-type sequences or, if unavailable, representative reference sequences for phylogenetic-taxonomic purposes are provided. The new species N. stachydis is described, and Striatoidium jaborosae is reduced to synonymy with Neoerysiphe macquii. Epitypes with ex-epitype sequences are designated for Alphitomorpha ballotae, A. labiatarum, Erysiphe galii, E. chelones, and E. galeopsidis. Based on phylogenetic analyses, it has been demonstrated that Neoerysiphe cumminsiana is confined to its type host, Roldana hartwegii (= Senecio seemannii), and other North and South American parasites on Asteraceae hosts, previously assigned to this species, pertain to N. macquii. The first record of N. macquii from Europe (Germany) on cultivated Bidens aurea was confirmed by sequencing. Sequence analysis of type material of N. rubiae reveals that this species should be excluded from Neoerysiphe; however, the true affinity of this taxon is not yet clear.
RESUMO
Bisporella as typically conceived is a genus of noticeable, bright yellow inoperculate discomycetes. This interpretation of the genus, however, is at odds with Bisporella pallescens, the current name of the type species of the genus; furthermore, the genus has been interpreted as including the unusual species Bisporella resinicola. By comparing morphological and molecular traits of species traditionally included in Bisporella, we show that the genus is polyphyletic, with many "typical" members of the genus belonging instead in Calycina in Pezizellaceae. Bisporella pallescens is conclusively linked with its asexual morph, Bispora antennata, and the genus Bisporella is abandoned as a later synonym of the monotypic genus Bispora (previously applied only to asexual fungi) and placed as sister to Hymenoscyphus in Helotiaceae. Bisporella resinicola is shown to represent an independent monotypic genus, Eustilbum, which so far is placed incertae sedis in Helotiales. Finally, "Bisporella" subpallida, like Bispora, belongs to Helotiaceae but is instead related to "Phaeohelotium" epiphyllum.