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Gary J. Samuels - One of the best experts on this subject based on the ideXlab platform.
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Trichoderma: Systematics, the Sexual State, and Ecology
Phytopathology, 2006Co-Authors: Gary J. SamuelsAbstract:Samuels, G. J. 2006. Trichoderma: Systematics, the sexual state, and ecology. Phytopathology 96:195-206. A chronology is presented that charts the development of a genus and species concept in Trichoderma. Eighty-nine species of Trichoderma have been named, and several species of Hypocrea have been linked to unnamed Trichoderma anamorphs. Eighty-three taxa of Trichoderma and their Teleomorphs, Hypocrea spp., have been included in phylogenetic analyses, including 11 species of Hypocrea with unnamed Trichoderma anamorphs. Phylogenetic analyses show that Trichoderma and Hypocrea are congeneric. Trichoderma species not linked to Hypocrea Teleomorphs are derived from among species that are linked to Teleomorphs, indicating sexual and asexual lineages are not independent of each other. Many more species remain to be discovered and described. Molecular phylogenetic analyses have revealed the existence of more species than have been recognized on the basis of morphology alone. A suggestion is made to modify the International Code of Botanical Nomenclature to enable adoption of a single generic name for Trichoderma/Hypocrea, with Trichoderma being the older and more utilitarian name. As increasing numbers of species are studied, the few morphological characters of anamorph and teleomorph have reached their limit for defining species. DNA-based characters have assumed an indispensable role. Exploration of new niches, such as within tree trunks and new geographic locations, have resulted in a substantial increase in the number of species of Trichoderma. Trichoderma is usually considered a genus of free-living soil fungi but evidence suggests that Trichoderma species may be opportunistic, avirulent plant symbionts as well as parasites of other fungi. Members of the genus Trichoderma are universally present in soils, although individual species may be either cosmopolitan (e.g., T. harzianum) or limited (e.g., T. viride) in their geographic distribution. To facilitate identification of species, a list of correctly identified strains of Trichoderma and their GenBank numbers for sequences of translation-elongation factor EF-1α and internal transcribed spacer rDNA is provided.
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Hypocrea atroviridis sp. nov., the teleomorph of Trichoderma atroviride
Mycologia, 2003Co-Authors: Sarah L. Dodd, Elke Lieckfeldt, Gary J. SamuelsAbstract:A new species, Hypocrea atroviridis, is described for the teleomorph of Trichoderma atroviride. Based on sequences of ITS-1, 5.8S, and ITS-2 regions of the rDNA complex and translation-elongation factor (EF-1α), T. atroviride and H. atroviridis form a well-supported clade within Trichoderma sect. Trichoderma. The conserved anamorphic phenotype of T. atroviride, observed for both conidial and ascospore derived cultures, was only found within that clade. In contrast, the teleomorph phenotype of H. atroviridis was morphologically indistinguishable from H. rufa, the teleomorph of T. viride. This Hypocrea phenotype may, therefore, be considered to be plesiomorphic within Trichoderma sect. Trichoderma, suggesting that genes controlling the expression of the teleomorph and anamorph evolve at different rates and that the genes controlling expression of the teleomorph are more conserved than are those controlling the expression of the anamorph.
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Hypocrea lixii, the teleomorph of Trichoderma harzianum
Mycological Progress, 2002Co-Authors: Priscila Chaverri, Gary J. SamuelsAbstract:Cultures derived from ascospores of Hypocrea lixii (= H. nigricans, H. lentiformis) produced the morphological species Trichoderma harzianum in pure culture. Trichoderma harzianum, the most commonly found species of the genus, is also one of the most species frequently used in biocontrol of plant pathogens. It has not been connected previously to a teleomorph. The connection was confirmed by DNA sequence analysis. Similar to the anamorph, the teleomorph collections have a wide geographic distribution. Described in the 19th century, Hypocrea lixii is epitypified by a collection from Thailand.
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classification of the mycoparasite gliocladium roseum in clonostachys as c rosea its relationship to bionectria ochroleuca and notes on other gliocladium like fungi
Mycologia, 1999Co-Authors: Hans-josef Schroers, Keith A Seifert, Gary J. Samuels, Walter GamsAbstract:AbstractBecause the common soil fungus and mycoparasite Gliocladium roseum differs from the type species of Gliocladium, G. penicillioides, in morphology, ecology, teleomorph, and DNA sequence data...
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molecular systematics of the hypocreales a teleomorph gene phylogeny and the status of their anamorphs
Botany, 1995Co-Authors: Stephen A Rehner, Gary J. SamuelsAbstract:Phylogenetic relationships among 40 species in the Hypocreales and Clavicipitales were inferred from sequence data obtained from the nuclear large-subunit ribosomal DNA. Cladistic analysis of these data support the monophyly of the Hypocreales, with the Clavicipitales derived from within the Hypocreales. Four groupings were resolved and are informally designated as the Hypocrea, Claviceps, Bionectria, and Nectria groups. Phylogenetic placement of Teleomorphs including Melanospora and cleistothecial taxa, such as Heleococcum, Mycoarachis, and Roumegueriella, demonstrate the facility of molecular phylogenies to accommodate taxa with highly modified morphologies. Similarly, the hypocrealean origins of the anamorph species Verticillium lecanii and Acremonium chrysogenum illustrate the potential of the molecular phylogenetic approach to accommodate anamorph isolates within the context of a teleomorph phylogeny. Together these results suggest that a comprehensive classification of the Hypocreales, inclusive of ...
Pedro W. Crous - One of the best experts on this subject based on the ideXlab platform.
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Discovery of a functional Mycosphaerella teleomorph in the presumed asexual barley pathogen Septoria passerinii
Fungal genetics and biology : FG & B, 2006Co-Authors: S.b. Ware, Pedro W. Crous, E.c.p. Verstappen, Jill Breeden, Jessica R. Cavaletto, Stephen B. Goodwin, Cees Waalwijk, Gert H. J. KemaAbstract:We studied the possibility of a teleomorph associated with the genotypically diverse septoria speckled leaf blotch (SSLB) pathogen of barley, Septoria passerinii. A teleomorph in the genus Mycosphaerella had been predicted previously based on phylogenetic analyses. This prediction was tested with experiments in the Netherlands and the United States by co-inoculating isolates with opposite mating types onto susceptible barley cultivars and monitoring leaves for sexual structures and for the discharge of ascospores. Characterization of putative hybrid progeny by both molecular (AFLP, RAPD, mating type, and ITS sequencing) and phenotypic analyses confirmed that a Mycosphaerella teleomorph of S. passerinii has been discovered approximately 125 years after the description of the anamorph. Progeny had recombinant genotypes of the molecular alleles present in the parents, and the identities of representative progeny isolates as S. passerinii were confirmed by ITS sequencing. A previously unknown sexual cycle explains the high degree of genetic variation among isolates found in nature. The experimental identification of a predicted teleomorph for S. passerinii indicates that cryptic sexual cycles may be common for many other ‘‘asexual’’ fungi with high levels of genotypic diversity.
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Togninia (Calosphaeriales) is confirmed as teleomorph of Phaeoacremonium by means of morphology, sexual compatibility, and DNA phylogeny
Mycologia, 2003Co-Authors: Lizel Mostert, Walter Gams, Pedro W. Crous, Johannes Z. Groenewald, Richard C. SummerbellAbstract:Petri disease, or black goo, is a serious dis- ease of vines in most areas where grapevines are cul- tivated. The predominant associated fungus is Phaeo- moniella chlamydospora (Chaetothyriales). Several species of Phaeoacremonium (Pm.) also are associated, of which Pm. aleophilum is the most common. Al- though no teleomorph is known for Phaeoacremon- ium, the genus Togninia previously has been linked to phaeoacremonium-like anamorphs. To investigate the possible anamorph-teleomorph connection of Phaeoacremonium to Togninia, anamorphs of Togni- nia minima, T. fraxinopennsylvanica and T. novae-zeal- andiae morphologically were compared with Pm. aleophilum and some representative cultures were mated in all combinations. Although no interspecies mating proved fertile, matings between isolates of Pm. aleophilum produced a Togninia teleomorph within 3-4 weeks. Certain field isolates of Pm. aleo- philum commonly produced the teleomorph, dem- onstrating that both mating types can occur in the same vine and thus also explaining the genetic diver- sity observed for this fungus in some vineyards. To elucidate the phylogenetic relationships among these taxa, isolates were subjected to sequence analysis of the nuclear ribosomal internal transcribed spacers (ITS1, ITS2) and the 5.8S rRNA gene, as well as por- tions of the translation elongation factor 1 alpha (EF-
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Eyespot of cereals revisited: ITS phylogeny reveals new species relationships
European Journal of Plant Pathology, 2003Co-Authors: Pedro W. Crous, Johannes Z. Groenewald, Walter GamsAbstract:Four species so far classified in Pseudocercosporella or Ramulispora (hyphomycetes) are associated with eyespot disease symptoms of cereals. Two of these have been linked to Teleomorphs that were described in Tapesia. Sequence data derived from the Internal Transcribed Spacer region (ITS1, 5.8S and ITS2) of the rDNA operon showed, however, that the eyespot fungi associated with Tapesia are not congeneric with Ramulispora sorghi, the type of Ramulispora. The genus name Tapesia is now rejected in favour of the conserved name Mollisia, which appears to comprise heterogeneous fungi. Tapesia yallundae is not closely related to the type of Mollisia, M. cinerea ,b ut clusters separately, being more closely allied to species with Cadophora anamorphs. A new holomorph genus, Oculimacula, is therefore proposed for Teleomorphs of the eyespot fungi, while the anamorphs are accommodated in Helgardia gen. nov.
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species concepts in the cylindrocladium floridanum and cy spathiphylli complexes hypocreaceae based on multi allelic sequence data sexual compatibility and morphology
Systematic and Applied Microbiology, 2001Co-Authors: Jichuan Kang, Pedro W. Crous, Conrad L. SchochAbstract:Summary Much attention has recently been devoted to the delimitation of species units in Cylindrocladium ( Cy .). In this regard the present study focuses on the taxa within the unresolved Cy. floridanum and Cy. spathiphylli species complexes. Maximum parsimony analyses of DNA sequences of ITS, β-tubulin and histone regions of rRNA genes, and mating experiments revealed a geographically isolated species of Cylindrocladium in the Cy. spathiphylli (teleomorph: Calonectria spathiphylli ) species complex. Cy. pseudospathiphylli sp. nov. (teleomorph: Ca. pseudospathiphylli sp. nov.) is described as a new phylogenetic, biological and morphological species. It is distinguished from Cy. spathiphylli by being homothallic, having smaller macroconidia, and distinct DNA sequences of β-tubulin and histone genes. Similarly, parsimony analysis of a combined data set also indicated several phylogenetic species to exist within Cy. floridanum (teleomorph: Ca. kyotensis ). Based on differences in vesicle morphology and conidium dimensions, the Canadian population of Cy. floridanum , formerly known as Cy. floridanum Group 2, is described as Cy. canadense sp. nov., while a further collection from Hawaii is described as Cy. pacificum sp. nov.
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cylindrocladium parasiticum sp nov a new name for c crotalariae
Fungal Biology, 1993Co-Authors: Pedro W. Crous, Michael J. Wingfield, Acelino C AlfenasAbstract:In an examination of the type specimens of Cylindrocladium ilicicola and its teleomorph Calonectria ilicicola, two distinct Cylindrocladium spp. were found. Furthermore, the Cylindrocladium anamorph produced by the type culture from which Calonectria ilicicola was originally described, was identical to the Cylindrocladium anamorph present on the type of Calonectria crotalariae. This suggests that Calonectria crotalariae is conspecific with the earlier described Calonectria ilicicola. Cylindrocladium crotalariae can be distinguished from Cylindrocladium ilicicola by its larger conidia and sphaeropedunculate vesicles. However, the name Cylindrocladium crotalariae was never validly published due to the omission of a Latin description. Cylindrocladium parasiticum is therefore proposed as a new name for Cylindrocladium crotalariae, and Calonectria ilicicola shown as its teleomorph with Calonectria crotalariae as a synonym. The teleomorph of Cylindrocladium ilicicola is shown to be Calonectria pyrochroa, with synonyms Calonectria daldiniana, Ophionectria puiggarii and Nectria abnormis.
Walter M. Jaklitsch - One of the best experts on this subject based on the ideXlab platform.
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European species of Hypocrea part II: species with hyaline ascospores
Fungal Diversity, 2011Co-Authors: Walter M. JaklitschAbstract:To date 75 species of Hypocrea / Trichoderma forming Teleomorphs are recognised in Europe. The 56 hyaline-spored species are here described in detail and illustrated in colour plates, including cultures and anamorphs. This number includes 16 new holomorphs, two new Teleomorphs and nine anamorphs of species previously described as Teleomorphs. Phylogenetic placement and relationships of the species are shown on the strict consensus tree, based on sequences of RNA polymerase II subunit b ( rpb2 ) and translation elongation factor 1 alpha ( tef1 ) exon, comprising 135 species of the genus Hypocrea / Trichoderma . All available holotypes of species described from Europe including some from North America have been examined. A dichotomous key to the species is provided primarily utilising ecological and morphological traits of the Teleomorphs and, where necessary, morphology of the anamorphs and cultures, and growth rates. Species descriptions are subdivided among five chapters, arranged primarily according to the larger phylogenetic clades, viz. section Trichoderma with 13 species, the pachybasium core group with 13 species including four species with stipitate stromata (‘ Podostroma ’), species forming large effused stromata with 10 species including the section Hypocreanum , 9 species of the Brevicompactum , Lutea and Psychrophila clades, and 11 residual species of various smaller clades or of unknown phylogenetic placement. Finally, a list comprising dubious names and species excluded from Hypocrea that are relevant for Europe, or species claimed to occur in Europe by other authors is provided. Hypocrea minutispora is by far the most common species in Europe. For H. moravica , H. subalpina and H. tremelloides the anamorphs are newly described. The anamorphs of the latter two species and H. sambuci produce hyaline conidia on unusual structures new to Trichoderma . These three species form a new subclade of the morphologically strikingly different section Longibrachiatum , which is currently only represented by H. schweinitzii in Europe as a holomorph. The subclade is not named yet formally due to low statistical support. H. fungicola f. raduli is described as the new species H. austriaca , while H. hypomycella was found not to belong to Hypocrea . The typification of H. pilulifera , H. tremelloides and H. lutea has been clarified. Gliocladium deliquescens , the anamorph of H. lutea , is combined in Trichoderma . Species are epitypified where appropriate. Anamorph names are established prospectively to avoid numerous new combinations in future when they may be possibly used as holomorphic names if the ICBN is altered accordingly.
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Nectria eustromatica sp. nov., an exceptional species with a hypocreaceous stroma.
Mycologia, 2010Co-Authors: Walter M. Jaklitsch, Hermann VoglmayrAbstract:A new species with remarkable morphology, Nectria eustromatica, is described, based on morphology of the teleomorph and anamorph, ecology and molecular phylogenetic analyses. Nectria eustromatica is characterized by sphaeroid perithecia immersed in pseudoparenchymatous stromata formed singly or collectively on a subiculum. Despite its deviating teleomorph morphology, it is placed within Nectria sensu stricto in phylogenetic analyses of a combined dataset of LSU, ITS, rpb2 and tef1 sequences with high internal support. Nectria eustromatica has been collected specifically on Hippocrepis (Coronilla) emerus in southern Europe. The anamorph of N. eustromatica shares morphological traits with the genera Stilbella and Tubercularia but produces non-phialidic macroconidia in addition to phialoconidia.
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European species of Hypocrea part II: species with hyaline ascospores
2010Co-Authors: Walter M. JaklitschAbstract:forming Teleomorphs are recognised in Europe. The 56 hyaline-spored species are here described in detail and illustrated in colour plates, including cultures and ana-morphs. This number includes 16 new holomorphs, two new Teleomorphs and nine anamorphs of species previously described as Teleomorphs. Phylogenetic placement and relationships of the species are shown on the strict consensus tree, based on sequences of RNA polymerase II subunit b (rpb2) and translation elongation factor 1 alpha (tef1) exon, comprising 135 species of the genus Hypocrea/Trichoderma. All available holotypes of species described from Europe including some from North America have been examined. A dichotomous key to the species is provided primarily utilising ecological and morphological traits of the teleo-morphs and, where necessary, morphology of the anamorph
P. Gillevet - One of the best experts on this subject based on the ideXlab platform.
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A new lichenicolous teleomorph is related to plant pathogens in Laetisaria and Limonomyces (Basidiomycota, Corticiales)
Mycologia, 2010Co-Authors: Paul Diederich, James D. Lawrey, Masoumeh Sikaroodi, P. GillevetAbstract:Molecular and morphological data were used to assess the taxonomic placement of an undescribed lichenicolous basidiomycete teleomorph collected in Luxembourg, Belgium and Germany. The new species is ecologically and morphologically similar to Marchandiobasidium aurantiacum, teleo- morph of the common bulbilliferous lichen pathogen Marchandiomyces aurantiacus. However phylogenetic analysis of nuclear and mitochondrial rDNA sequenc- es indicated a close relationship of the new species— not to M. aurantiacum but to turf grass pathogens in genera Laetisaria and Limonomyces, including the generic type of Laetisaria. We are including the new species in Laetisaria based on strong statistical support for the clade containing these Teleomorphs and several Marchandiomyces anamorphs. The mor- phological and ecological diversity of this clade indicates a potentially significant evolutionary role played by lichen-associated species in the Corticiales.
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Short title: New lichenicolous teleomorph A new lichenicolous teleomorph is related to plant pathogens in Laetisaria and Limonomyces (Basidiomycota, Corticiales)
2010Co-Authors: Paul Diederich, James D. Lawrey, Masoumeh Sikaroodi, P. GillevetAbstract:Molecular and morphological data were used to assess the taxonomic placement of an undescribed lichenicolous basidiomycete teleomorph collected in Luxembourg, Belgium and Germany. The new species is ecologically and morphologically similar to Marchandiobasidium aurantiacum, teleomorph of the common bulbilliferous lichen pathogen Marchandiomyces aurantiacus. However phylogenetic analysis of nuclear and mitochondrial rDNA sequences indicated a close relationship of the new species—not to M. aurantiacum but to turf grass pathogens in genera Laetisaria and Limonomyces, including the generic type of Laetisaria. We are including the new species in Laetisaria based on strong statistical support for the clade containing these Teleomorphs and several Marchandiomyces anamorphs. The morphological and ecological diversity of this clade indicates a potentially significant evolutionary role played by lichen-associated species in the Corticiales.
Rytas Vilgalys - One of the best experts on this subject based on the ideXlab platform.
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Rhacophyllus and Zerovaemyces —Teleomorphs or anamorphs?
TAXON, 2000Co-Authors: Scott A. Redhead, Keith A Seifert, Rytas Vilgalys, Jean-marc MoncalvoAbstract:The originally monotypic genus Rhacophyllus was conceived for an agaric-like fungus that bore sheets of miniature sclerotium-like bodies (lysomeres) in place of lamellae. Subsequently it was demonstrated that a "normal" Coprinus-like teleomorph exists as an alternative state (morph). Following this discovery, most authors have treated Rhacophyllus as an anamorph. Ontogenetic studies indicate that the Rhacophyllus state is a variation on basidiome production. Rhacophyllus apparently was rediscovered and redescribed as a new genus Zerovaemyces, for which a new family, Zerovaemycetaceae, and a new order, Loculomycetes, were also described, all as Teleomorphs. Nomenclatural application of these names are analysed, and it is concluded that Rhacophyllus (and Zerovaemyces, Zerovaemnycetaceae) are best considered to be nomina anarmorphosium. These decisions affect the naming of other taxa newly resolved molecularly. An analogous second case of modified basidiomes involves the anamorph Decapitatus gen. nov., described here for the well-known gemmiferous state of Mycena citricolor, Decapitatus flavidus comb. nov. (= Stilbum flavidum).
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Molecular systematics and population biology of Rhizoctonia
Annual Review of Phytopathology, 1994Co-Authors: Rytas Vilgalys, Marc A CubetaAbstract:Fungi classified as Rhizoctonia species represent an amalgam of taxonomically diverse groups that differ in many significant features, including their sexual stages (teleomorph), asexual stages (anamoI]'lh), and other characters (101, 106, 107). Because of the importance of many Rhizoctonia species as plant pathogens, a variety of useful approaches have been developed for identifying many groups of Rhizoctonia spp. based on ultrastructural features, information from Teleomorphs, anastomosis behavior, and molecular biology. This review summarizes recent progress in understanding patterns of genetic diversity revealed through application of molecular data, and the relation of genetic diversity to the taxonomy and population biology of Rhizoctonia. Several reviews have summarized the most current framework for under standing diversity within Rhizoctonia , including the R. solani complex (79), binucleate Rhizoctonia (48), and other Rhizoctonia (101). Most Rhizoctonia can now usually be classified into major groups based on teleomorph associ ation, as well as into more narrowly defined intraspecific groups (1, 5,79). Progress in understanding the biology and pathology of Rhizoctonia can be traced to the realization that genetically diverse groups exist at several levels of organization:
