Mycologia最新文献

Despite their global presence and ubiquity, members of the class Geoglossomycetes (Pezizomycotina, Ascomycota) are understudied systematically and ecologically. These fungi have long been presumed saprobic due to their occurrence in or near leaf litter and soils. Additionally, they lack an apparent association with other organisms, reinforcing this perception. However, observations of sporocarps near ericaceous shrubs have given rise to an alternative hypothesis that members of Geoglossomycetes may form ericoid mycorrhizae or ectomycorrhizae. This claim, however, has yet to be confirmed via microscopy or amplicon-based studies examining root communities. As a result, our current understanding of their ecology is based on cursory observations. This study presents a comparative analysis of genomic signatures related to ecological niche to investigate the hypothesis of an ericoid mycorrhizal or ectomycorrhizal ecology in the class. We compared the carbohydrate-active enzyme (CAZyme) and secondary metabolite contents of six newly sequenced Geoglossomycetes genomes with those of fungi representing specific ecologies across Pezizomycotina. Our analysis reveals CAZyme and secondary metabolite content patterns consistent with ectomycorrhizal (EcM) members of Pezizomycotina. Specifically, we found a reduction in CAZyme-encoding genes and secondary metabolite clusters that suggests a mutualistic ecology. Our work includes the broadest taxon sampling for a phylogenomic study of Pezizomycotina to date. It represents the first functional genomic and genome-scale phylogenetic study of the class Geoglossomycetes and improves the foundational knowledge of the ecology and evolution of these understudied fungi.

Bats can be affected by fungal pathogens such as Pseudogymnoascus destructans, the causative agent of the white-nose syndrome. Their body surface can also be colonized by fungal commensals or carry transient fungal species and participate in their dispersal. In this study, 114 bat specimens belonging to seven species were sampled from various locations in northern Belgium. Culture-based methods revealed an important mycological diversity, with a total of 209 different taxa out of the 418 isolates. Overall, a mean of 3.7 taxa per bat was recorded, but significant differences were observed between sampling sites and seasons. The mycobiomes were dominated by cosmopolitan and plant-associated species, in particular from the genera Cladosporium, Penicillium, and Aspergillus. Other species known to be related to bats or their environment, such as Apiotrichum otae, were also retrieved. Sampling of hibernacula indicated that diverse fungal species can inhabit these sites, including a yet undescribed Pseudogymnoascus species, distinct from Ps. destructans, namely, Ps. cavicola.

Three species of the rust fungus genus Blastospora, Bl. betulae, Bl. itoana, and Bl. smilacis, have been reported in East Asia. Although their morphological characteristics and life cycles have been investigated, their phylogenetic positions have not been clarified sufficiently. Phylogenetic analysis showed that these three species were included into Zaghouaniaceae of Pucciniales. However, Bl. betulae was phylogenetically distinct from Bl. itoana and Bl. smilacis and different from other genera. Based on this result, and applying recent International Code of Nomenclature decisions/recommendations/requirements, Botryosorus, gen. nov., and Bo. deformans,, comb. nov., were applied for Bl. betulae. Two new combinations, Bl. radiata for Bl. itoana and Bl. makinoi for Bl. smilacis, were also applied. Their host plants and distribution were described based on literature records. Zaghouania yunnanensis, comb. nov., was proposed for Cystopsora yunnanensis as a result of this analysis.

Metabarcoding studies of fungal communities rely on curated databases for assigning taxonomy. Any host or other nonfungal environmental sequences that are amplified during polymerase chain reaction (PCR) are inherently assigned taxonomy by these same databases, possibly leading to ambiguous nonfungal amplicons being assigned to fungal taxa. Here, we investigated the effects of including nonfungal outgroups in a fungal taxonomic database to aid in detecting and removing these nontarget amplicons. We processed 15 publicly available fungal metabarcode data sets and discovered that roughly 40% of the reads from these studies were not fungal, although they were assigned as Fungus sp. when using a database without nonfungal outgroups. We discuss implications for metabarcoding studies and recommend assigning taxonomy using a database with outgroups to better detect these nonfungal amplicons.

Canopy soils occur on tree branches throughout the temperate rainforests of the Pacific Northwest Coast and are recognized as a defining characteristic of these ecosystems. Certain tree species extend adventitious roots into these canopy soil environments. Yet, research on adventitious root-associated fungi remains limited. Our study used microscopy to compare fungal colonization intensity between canopy and forest floor roots of old-growth bigleaf maple (Acer macrophyllum) trees. Subsequently, two high-throughput sequencing platforms were used to explore the spatial and seasonal variation of root-associated fungi between the two soil environments over one year. We found that canopy and forest floor roots had similar colonization intensity and were associating with a diversity of arbuscular mycorrhizal fungi and other potential symbionts, many of which were resolved to species level. Soil environment and seasonality affected root-associated fungal community composition, and several fungal species were indicative of the canopy soil environment. In Washington State's (USA) temperate old-growth rainforests, these canopy soil environments host a unique suite of root-associated fungi. The presence of arbuscular mycorrhizae provides further evidence that adventitious roots form fungal associations to exploit canopy soils for resources, and there may be novel relationships forming with other fungi. These soils may be providing a redundancy compartment (i.e., "nutrient reserve"), imparting a resiliency to disturbances for certain old-growth trees.

Optimization of xylanase and cellulase production by a newly isolated Aspergillus fumigatus strain grown on Stipa tenacissima (alfa grass) biomass without pretreatment was carried out using a Box-Behnken design. First, the polysaccharides of dried and ground alfa grass were characterized using chemical methods (strong and diluted acid). The effect of substrate particle size on xylanase and carboxymethylcellulase (CMCase) production by the selected and identified strain was then investigated. Thereafter, experiments were statistically planned with a Box-Behnken design to optimize initial pH, cultivation temperature, moisture content, and incubation period using alfa as sole carbon source. The effect of these parameters on the two enzyme production was evaluated using the response surface method. Analysis of variance was also carried out, and production of the enzymes was expressed using a mathematical equation depending on the influencing factors. The effects of individual, interaction, and square terms on production of both enzymes were represented using the nonlinear regression equations with significant R² and P-values. Xylanase and CMCase production levels were enhanced by 25% and 27%, respectively. Thus, this study demonstrated for the first time the potential of alfa as a raw material to produce enzymes without any pretreatment. A set of parameter combinations was found to be effective for the production of xylanase and CMCase by A. fumigatus in an alfa-based solid-state fermentation.

Based on a study of 255 collections from four continents and four floristic kingdoms, we describe 15 new species of the genus Lycogala. The new species, all morphologically close to L. epidendrum, L. exiguum, and L. confusum, differ from each other by the structure of the peridium and, in some cases, also by the color of the fresh spore mass and the ornamentation of the capillitium and spores. Species delimitation is confirmed by two independently inherited molecular markers, as well as previously performed tests of reproductive isolation and genetic distances. We studied authentic material of L. exiguum and L. confusum and found fresh specimens of these species, which allowed us to obtain molecular barcodes and substantiate the separation of new species from these taxa. We propose to retain the name L. epidendrum for the globally most abundant species, for which we provide a more precise description and a neotypification. Two formerly described species, L. leiosporum and L. fuscoviolaceum, we consider to be dubious. We do not recognize the species L. terrestre.

Graphium species form a well-supported monophyletic lineage within the Microascales (Ascomycota). Members of this genus can be found in association with bark beetles, as well as on tree wounds and in soils. During surveys of bark and ambrosia beetle-associated fungi and cavities made by woodpeckers on hardwood trees in Poland, many isolates with an affinity to Graphium were recovered. They were identified based on their morphological characters and sequence data for the internal transcribed spacer (ITS), 28S rDNA, β-tubulin (TUB2), and translation elongation factor 1-α (TEF1) gene regions. The results revealed five new species, described here as G. brachiatum, G. longistipitatum, G. polonicum, G. radicatum, and G. trypophloei.

Due to their high number and variety, simple sequence repeats in DNA are a valuable source of genetic markers widely used in population genetics, genetic diversity, and fingerprinting. Schizophyllum commune is a cosmopolitan basidiomycete and a valuable object for biotechnology and mycology. It is often used as a model organism in genetic and population studies. Numerous genome sequences of S. commune are available in the National Center for Biotechnology Information (NCBI) database, allowing for a meticulous study of the distribution of simple tandem nucleotide repeats in the genomes of different strains, based on their origin. Analysis of the average density of simple tandem repeats in the genomes of S. commune fungi reveals the division of cultures into groups based on the USA, Ru (Russian Federation), and EA (South Korea, Japan, China) populations. Intensive point mutations lead to the accumulation and dominance of mononucleotide (C)n and dinucleotide (CG)n motifs in fungal genomes. Results show that the GCT motif contributes more to the divergence of the Ru population, whereas CTC, GAG, and GGA motifs contribute to the divergence of the USA population. Strains MG53 (China) and IUM1114-SS01 (South Korea: Incheon) from the EA population occupy a separate position, mainly because of the CGA motif. The divergence in quantitative traits of motifs between populations provides evidence of the evolutionary transformation of fungal genomes under environmental factors.

Wild mushroom (macrofungi) picking has become a popular activity in Israel in recent years. Besides the estimated 135 edible species, the mycobiota of Israel includes also around 65 poisonous and potentially dangerous species. We conducted a long-term retrospective study to monitor the frequency, severity, seasonal character, species composition, and geographic distribution of mushroom exposure and poisoning in Israel. Using data collected by the Israel Poison Information Center in Rambam Health Care Campus, Haifa, during the years 2010-2021, we report that only 4% of cases of exposures due to biological agents were caused by mushrooms. Males were significantly (P < 0.004) more affected than females. Most cases involved either above 18 years of age (41%) or below the age of 6 years (39%). Most of the children under 6 years of age did not develop signs or symptoms of toxicity. During 2017-2021, 128 cases (82.5%) involved the consumption of raw mushrooms, mostly by children under 6 years of age. The most common season of mushroom exposure was rainy winters (P < 0.05). Mushrooms collected from irrigated lawns in the summer also posed a risk. Ingestion of Chlorophyllum molybdites was the leading mushroom ingestion in summer and that of Inocybe species in winter. Our study contributes to improved awareness of mushroom exposure and poisoning patterns among the Israeli population.