Mycologia最新文献

During the 1970s and 1980s, L. R. Hesler and A. H. Smith, alone, together, or Smith with other authors such as V. S. Evenson and D. H. Mitchel, described numerous North American taxa in Hebeloma. With the inclusion of an early work by Smith and a later work by E. Grilli, who described a species based on material from Smith, 130 taxa were described and form the subject of this paper. Apart from two taxa that were (deliberately) invalidly published and two that were illegitimately published, all others are valid and legitimate names. After study of morphology, habitat, and location of collection (based on available material and information) as well as molecular analysis (insofar as this was successful), of these 128 validly published taxa we regard 14 as being current names; the remaining 114 are synonymized with other current names. These 14 species are Hebeloma albomarginatum, H. alpinicola, H. angelesiense, H. caulocystidiosum, H. immutabile, H. incarnatulum, H. kelloggense, H. mackinawense, H. nitidum, H. olympianum, H. parcivelum, H. praeolidum, H. pungens, and H. sporadicum. This brings up the number of currently recognized, validly published, Hebeloma species in America to 72.

Cortinarius sect. Camphorati consists of telamonioid species with violet basidioma, strong odor, and distinct cheilocystidia. In this study, phylogenetic analysis based on nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and partial nuc rDNA 28S sequences has revealed three new species of the section from southwestern China, namely, C. longicystidiatus, C. megacystidiatus, and C. paraputorius, and a newly recorded species from southwestern China, viz., C. camphoratus, supplemented by the support from calculations of genetic distances of ITS sequences. Detailed descriptions of the four species are given with photographs, and their micromorphological characteristics are statistically compared. For species delimitation within the section, the size of basidiospores, the morphology of cheilocystidia, and the associated vegetation types and tree species are informative. A key to species in section Camphorati from the Northern Hemisphere is provided, and their geographic distributions and ecology are discussed.

Diverse fungi colonize plant roots worldwide and include species from many orders of the phylum Ascomycota. These fungi include taxa with dark septate hyphae that colonize grass roots and may modulate plant responses to stress. We describe a novel group of fungal isolates and evaluate their effects on the grass Bouteloua gracilis in vitro. We isolated fungi from roots of six native grasses from 24 sites spanning replicated latitudinal gradients in the south-central US grasslands and characterized isolates phylogenetically using a genome analysis. We analyzed 14 isolates representing a novel clade within the family Montagnulaceae (order Pleosporales), here typified as Pleoardoris graminearum, closely related to the genera Didymocrea and Bimuria. This novel species produces asexual, light brown pycnidium-like conidioma, hyaline hyphae, and chlamydospores when cultured on quinoa and kiwicha agar. To evaluate its effects on B. gracilis, seeds were inoculated with one of three isolates (DS304, DS334, and DS1613) and incubated at 25 C for 20 d. We also tested the effect of volatile organic compounds (VOCs) produced by the same isolates on B. gracilis root and stem lengths. Isolates had variable effects on plant growth. One isolate increased B. gracilis root length up to 34% compared with uninoculated controls. VOCs produced by two isolates increased root and stem lengths (P < 0.05) compared with controls. Internal transcribed spacer ITS2 metabarcode data revealed that P. graminearum is distributed across a wide range of sites in North America (22 of 24 sites sampled), and its relative abundance is influenced by host species identity and latitude. Host species identity and site were the most important factors determining P. graminearum relative abundance in drought experiments at the Extreme Drought in the Grasslands Experiment (EDGE) sites. Variable responses of B. gracilis to inoculation highlight the potential importance of nonmycorrhizal root-associated fungi on plant survival in arid ecosystems.

The Globisporangium ultimum (formerly Pythium ultimum) species complex was previously composed of two morphological varieties: var. ultimum and var. sporangiiferum. Prior attempts to resolve this morphology-based species complex using molecular techniques have been inconclusive or conflicting. The increased availability of sequenced genomes and isolates identified as G. ultimum var. ultimum and var. sporangiiferum has allowed us to examine these relationships at a higher resolution and with a broader scope than previously possible. Using comparative genomics, we identified highly variable gene regions and designed primers for four new protein-coding genes for phylogenetics. These were then used alongside three known markers to generate a nuclear multigene genealogy of the species complex. From a collection of 163 isolates belonging to the target taxa, a subset of 29 was chosen to be included in this study (verified with nuclear rDNA internal transcribed spacer 1 [ITS1] and mitochondrial cytochrome c oxidase subunit 1 [cox1] sequences). Seventeen isolates of var. ultimum were selected to be representative of variations in genotype, morphology, and geographic collection location. The 12 isolates of var. sporangiiferum included all available specimens identified either morphologically (in previous studies) or through sequence similarity with ITS1 and cox1. Based on the fulfillment of reciprocal monophyly and observed genealogical concordance under the genealogical concordance phylogenetic species recognition, we determined that the Globisporangium ultimum species complex is composed of four genetically distinct species: Globisporangium ultimum, Globisporangium sporangiiferum, Globisporangium solveigiae, and Globisporangium bothae.

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.

Two Cerrado rust fungi, Phakopsora rossmaniae and Aplopsora hennenii, described in 1993 and 1995 and originally assigned to families Phakopsoraceae and Ochropsoraceae, respectively, were subjected to molecular phylogenetic analyses using fragments of the nuc 28S and 18S rDNA and mitochondrial cytochrome c oxidase subunit 3 (CO3) gene. Although both taxa were morphologically well placed in their original genera, they were shown to belong in a strongly supported new lineage within the Raveneliineae distant from the Phakopsoraceae and Ochropsoraceae. Therefore, we properly treated this lineage as the new genus Cerradopsora now harboring C. rossmaniae (type species) and C. hennenii. However, this novel phakopsoroid genus remains in uncertain familial position without support to be included in any of the families that share space within the Raveneliineae.

Habitat heterogeneity is a key driver of biodiversity of macroorganisms, yet how heterogeneity structures belowground microbial communities is not well understood. Importantly, belowground microbial communities may respond to any number of abiotic, biotic, and spatial drivers found in heterogeneous environments. Here, we examine potential drivers of prokaryotic and fungal communities in soils across the heterogenous landscape of the imperiled Florida scrub, a pyrogenic ecosystem where slight differences in elevation lead to large changes in water and nutrient availability and vegetation composition. We employ a comprehensive, large-scale sampling design to characterize the communities of prokaryotes and fungi associated with three habitat types and two soil depths (crust and subterranean) to evaluate (i) differences in microbial communities across these heterogeneous habitats, (ii) the relative roles of abiotic, biotic, and spatial drivers in shaping community structure, and (iii) the distribution of fungal guilds across these habitats. We sequenced soils from 40 complete replicates of habitat × soil depth combinations and sequenced the prokaryotic 16S and fungal internal transcribed spacer (ITS) regions using Illumina MiSeq. Habitat heterogeneity generated distinct communities of soil prokaryotes and fungi. Spatial distance played a role in structuring crust communities, whereas subterranean microbial communities were primarily structured by the shrub community, whose roots they presumably interacted with. This result helps to explain the unexpected transition we observed between arbuscular mycorrhiza-dominated soils at low-elevation habitats to ectomycorrhiza-dominated soils at high-elevation habitats. Our results challenge previous notions of environmental determinism of microbial communities and generate new hypotheses regarding symbiotic relationships across heterogeneous environments.

A Fusarium species associated with sunflower based on multilocus genealogy, morphological, physiological, ecological, mating type, and mycotoxin production data is formally described as the newly discovered species Fusarium bilaiae. The F. bilaiae strains formed a genealogically exclusive lineage within the African clade of the F. fujikuroi species complex. Comparison of morphological characteristics of F. bilaiae strains with those of the closely related F. phyllophilum strain NRRL 13617 revealed similarities in the main micromorphology of both species: production of numerous one-celled microconidia in false heads and short chains on monophialides and polyphialides and the absence of macroconidia and sporodochia. There was a slight but significant distinction between the two species when the strains were grown on different agar media, as well as in the shape and width of microconidia. Fusarium bilaiae strains isolated from symptomatic sunflower were not pathogenic to members of the Asteraceae tested; apparently, they live as saprophytes or endophytes in sunflower tissues. A difference between the strains of the two species in the production of mycotoxins was demonstrated with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis. On autoclaved rice, F. bilaiae did not produce fumonisins and beauvericin but produced moniliformin, whereas F. phyllophilum produced all these mycotoxins. A polymerase chain reaction (PCR) assay specific for mating type alleles identified F. bilaiae as a putative heterothallic species with MAT1-1 and MAT1-2 idiomorphs, but laboratory crosses were unsuccessful. Determining the area and host range of the new endophytic species F. bilaiae is a priority for future research.

Species of the phylum Blastocladiomycota, early-diverging zoosporic (flagellated) lineages of fungi, are vastly understudied. This phylum includes the genus Coelomomyces, which consists of more than 80 fungal species that are obligate parasites of arthropods. Known Coelomomyces species lack a complete asexual life cycle, instead surviving through an obligate heterecious alternation of generations life cycle. Despite their global distribution and interesting life cycle, little is known about the genomics of any Coelomomyces species. To address this, we generated three draft-level genomes and annotations for C. lativittatus representing its haploid meiospore, orange gamete, and amber gamete life stages. These draft genome assemblies ranged in size from 5002 to 5799 contigs, with a total length of 19.8-22.8 Mb and a mean of 7416 protein-coding genes. We then demonstrated the utility of these genomes by combining the draft annotations as a reference for analysis of C. lativittatus transcriptomes. We analyzed transcriptomes from across host-associated life stages, including infected larvae and excised mature sporangia from the mosquito Anopheles quadrimaculatus. We identified differentially expressed genes and enriched GO terms both across and within life stages and used these to make hypotheses about C. lativittatus biology. Generally, we found the C. lativittatus transcriptome to be a complex and dynamic expression landscape; GO terms related to metabolism and transport processes were enriched during infection and terms related to dispersal were enriched during sporulation. We further identified five high mobility group (HMG)-box genes in C. lativittatus, three belonging to clades with mating type (MAT) loci from other fungi, as well as four ortholog expansions in C. lativittatus compared with other fungi. The C. lativittatus genomes and transcriptomes reported here are a valuable resource and may be leveraged toward furthering understanding of the biology of these and other early-diverging fungal lineages.