ISSN:0008-4026    

DOI:10.1139/b98-093

出版商:NRC Research Press    

年代:1998

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b98-092

出版商:NRC Research Press    

年代:1998

数据来源: NRC

摘要:

Based on nuclear encoded small subunit (18S) rDNA sequences, a taxonomic reappraisal ofGraphium(anamorphic fungi) was undertaken using neighbour-joining (NJ) and fast DNA maximum likelihood (fastDNAml) methods and compared with traditional classifications. In common withGraphium putredinis,Graphium penicillioides(the lectotype species) was found to be related to the Microascales, not the Ophiostomatales as previously believed. Both species might be heterogenous and should be treated as species aggregates. The representative mode of conidiogenesis for these two species was nodular-annellidic, rather than the dense-annellidic mode characteristic of the synnematous ophiostomatalean anamorphs.Graphiumis emended to be restricted toG. penicillioides,G. putredinis, and related synnematous anamorphs ofPetriellaandPseudallescheria, and a nomenclator for the nine species presently accepted inGraphiumis presented.Pesotum, originally characterized mainly by sympodial conidiogenesis, is emended to include synnematous anamorphs ofOphiostomaspecies formerly included in a variety of genera with sympodial to dense-annellidic conidiogenesis. Eight new combinations inPesotumare included in a nomenclator for the 26 species currently known. Three new combinations fromCeratocystistoOphiostomaare proposed for species withPesotumanamorphs. The holomorph ofGraphium calicioideshas affinities to the black yeasts and should be classified in the Chaetothyriales. However, the critical morphological, loculoascomycetous characters of the teleomorph are not completely documented. Interpreted from the molecular context, the morphological similarities between these three groups of anamorphs are homoplasies and examples of convergent evolution.Key words: Chaetothyriales,Graphium, Microascales, Ophiostomatales,Pesotum, 18S (SSU) rDNA sequences.

ISSN:0008-4026    

DOI:10.1139/b98-089

出版商:NRC Research Press    

年代:1998

数据来源: NRC

摘要:

A neotype is selected forTrichoderma koningii. The species is characterized by morphological and molecular characters, the latter including polymerase chain reaction (PCR) fingerprinting and restriction fragment length polymorphism (RFLP) analysis and direct sequencing of the variable regions of the rDNA (internal transcribed spacer 1 (ITS-1) and internal transcribed spacer (ITS-2)). The neotype was selected from among four cultures obtained from soil at the type locality. These cultures were compared with a broader collection ofTrichodermastrains and anamorphs ofHypocreathat morphologically conform toT. koningii. Comparison was also made with members ofTrichodermasect.Trichodermaand of theHypocrea schweinitziicomplex (Trichodermasect.Longibrachiatum). According to its ITS sequences,T. koningiiis a member of sect.Trichoderma, showing very low variability in comparison withTrichoderma virideandTrichoderma atroviride. We found five additional strains from various geographical regions that are identical to the neotype in morphology and in their sequences. One of them isHypocrea koningiisp.nov., which we consider to be the teleomorph ofT. koningii. PCR fingerprint patterns demonstrate the high genetic similarity of these nine strains. There was only low similarity in molecular characters betweenT. koningiiand theH. schweinitziicomplex despite morphological similarities.Key words: Hypocreales,Hypocrea muroiana, Hypocrea rufa, internal transcribed spacer, systematics.

ISSN:0008-4026    

DOI:10.1139/b98-090

出版商:NRC Research Press    

年代:1998

数据来源: NRC

摘要:

Several species ofMycosphaerella, some of which have been linked to cercosporoid anamorphs, have been described fromPlatanus. A reassessment of these species revealed several synonymies and incorrect anamorph-teleomorph connections.Mycosphaerella albocrustata(Schwein.) Crous & Corlett is recognized as an earlier name forMycosphaerella platanifolia(Cooke) F.A. Wolf, a species with no known anamorph.Mycosphaerella stigmina-plataniF.A. Wolf is shown to be the teleomorph of a new anamorph species,Xenostigmina wolfii, which has aCercostigminasynanamorph. The latter synanamorph was previously confused withCercospora platanicolaEllis & Everh., which has recently been placed inPseudocercospora.Xenostigmina wolfiiis known only from the United States and is distinguished fromStigmina platani(Fuckel) Sacc. andStigmina platani-racemosaeDearn. & Barthol. by its mode of conidiogenesis, longer conidia, andCercostigminasynanamorph.Key words:Mycosphaerella, Platanus, Stigmina, systematics.

ISSN:0008-4026    

DOI:10.1139/b98-096

出版商:NRC Research Press    

年代:1998

数据来源: NRC

摘要:

Cultures of many isolates ofUlocladiumPreuss mature with conidium populations dominated by dark, obovoid to spherical, densely ornamented spores similar to those of typicalUlocladium atrumPreuss. Early-growth conidia of such isolates frequently are quite different morphologically from those ofU. atrumand are considered to be useful in defining species within aU. atrumspecies group. Four species are compared from this viewpoint in both early-growth and late-growth stages:U. atrum, Ulocladium cucurbitae(Letendre & Roumeguère) Simmons,Ulocladium multiformeSimmons sp.nov. (from soil), andUlocladium dauciSimmons sp.nov. (from seed ofDaucus carotaL.).Key words:Ulocladium, classification, conidium variability

ISSN:0008-4026    

DOI:10.1139/b98-091

出版商:NRC Research Press    

年代:1998

数据来源: NRC

摘要:

A new fungal taxon,Fibulobasidium sirobasidioidesBandoni sp.nov., is described and illustrated. Basidiomata develop beneath the bark of recently dead branches and trunks ofAcer macrophyllumPursh in British Columbia; they are characterized by superficiallySirobasidium-like chains of basidia.Key words:Fibulobasidium, Sirobasidium, Sirobasidiaceae, taxonomy.

ISSN:0008-4026    

DOI:10.1139/b98-172

出版商:NRC Research Press    

年代:1998

数据来源: NRC

摘要:

Some aspects of development and biology ofTremella mesentericaand two closely allied species are discussed; some associated fungi are noted.Tremella brasiliensis, previously known only from neotropical areas, is reported from Japan; an extended description is provided. One North American species,Tremella mesenterellaBandoni & Ginns, is described as new, and other taxa with superficially similar basidiocarps are discussed.Key words: Tremellaceae,Tremella, T. mesenterica, T. mesenterella, T. philippinensis, T. rufobrunnea, conidium ontogeny, basidiome development.

ISSN:0008-4026    

DOI:10.1139/b98-094

出版商:NRC Research Press    

年代:1998

数据来源: NRC

摘要:

Marielliottia, a new genus of hyphomycetes, is described. Three species formerly treated inDrechsleraare included:D. biseptata, the type,D. dematioidea, andD. triseptata. The species differ fromDrechslerain having mostly three-septate, obovoid to ovoid conidia that germinate primarily from the basal cell, occasionally from the apical cell, and not from the central cells. These fungi are occasional parasites of cereals and grasses, are sometimes seed borne, and may infect nongrass plants. The type species is implicated in mycotoxicosis of sheep and produces zaragozoic acid A.Key words: mycotoxins,Helminthosporium, M. biseptata, M. dematioidea, M. triseptata.

ISSN:0008-4026    

DOI:10.1139/b98-108

出版商:NRC Research Press    

年代:1998

数据来源: NRC

摘要:

Unlike most phialide-producing fungi that liberate a multiplicity of conidia from each conidiogenous cell, only single conidia are formed on phialide-like conidiogenous cells inAphanocladium, Verticimonosporium, and some species ofSibirina. A group of isolates obtained from soil of nativeArtemisia tridentata(sagebrush) grassland in Wyoming and from desert soil in Iraq is compared with these genera and classified as a fourth genus,Stanjemonium, honouring Stanley J. Hughes. Phylogenetic analyses of partial nuclear small- (18S) and large-subunit (28S) rDNA sequences indicate thatStanjemoniumspp. form a monophyletic group withEmericellopsis. Sequences from the nuclear 18S and 28S rDNA were too conserved to resolve morphological species ofStanjemonium; however, phylogenetic analysis of b-tubulin and translation elongation factor 1a gene exons and introns resolved all species distinguished morphologically. Numerous conidiogenous cells or denticles are scattered along the cells of aerial hyphae inAphanocladiumandStanjemoniumspp., very rapidly collapsing into denticles in the former, somewhat more persistent and leaving broad scars in the latter. InCladobotryum-SibirinaandVerticimonosporiumspp., conidiogenous cells are discrete in terminal and intercalary whorls; phialides of the latter taxon are particularly swollen. The taxonomy ofAphanocladiumis not yet resolved. Two species are recognized inVerticimonosporium. Three new species ofStanjemoniumare described, and one new combination fromAphanocladiumis proposed, along with one new species ofCladobotryum.Key words:Aphanocladium, Cladobotryum, conidiogenesis, hyphomycetes, molecular phylogeny, phialide, Stanjemonium, systematics,Verticimonosporium.

ISSN:0008-4026    

DOI:10.1139/b98-104

出版商:NRC Research Press    

年代:1998

数据来源: NRC