The hyphomyceteTeberdinia hygrophilagen. nov., sp. nov. and related anamorphs ofPseudeurotiumspecies

Application of Magnetized Ionized Water and Bacillus subtilis Improved Saline Soil Quality and Cotton Productivity

Soil salinization, a significant global challenge, threatens sustainable development. This study explores the potential of magnetized ionized water irrigation and Bacillus subtilis application to mitigate this issue. The former method is hypothesized to enhance soil salt leaching, while the latter is expected to improve soil nutrient availability, thereby increasing microbial diversity. To address the unclear impact of these interventions on soil quality and cotton productivity, this study employs four different experimental methods: magnetized ionized water irrigation (M), application of 45 kg ha-1B. subtilis (B), a combination of 45 kg ha-1B. subtilis with magnetized ionized water irrigation (MB), and a control treatment with no intervention (CK). This study aims to clarify the effects of these treatments on soil bulk density (BD), field capacity (FC), salinity and alkalinity, nutrient content, microbial activity, and cotton crop yield and quality. Additionally, it aims to evaluate the efficacy of these methods in improving saline soil conditions by developing a soil quality index. The results showed that using magnetized ionized water for irrigation and applying B. subtilis, either alone or together, can effectively lower soil pH and salt levels, enhance microbial diversity and abundance, and improve the yield and quality of cotton. Notably, B. subtilis application significantly decreased BD and enhanced FC and nutrient content (p < 0.05). A correlation was found where soil nutrient content decreased as pH and salt content increased. Furthermore, a strong correlation was observed between the major soil bacteria and fungi with BD, FC, and salt content. Comparatively, M, B, and MB significantly boosted (p < 0.01) the soil quality index by 0.21, 0.52, and 0.69 units, respectively, and increased (p < 0.05) cotton yield by 5.7%, 14.8%, and 20.1% compared to CK. Therefore, this research offers eco-friendly and efficient methods to enhance cotton production capacity in saline soil.

The First Comprehensive Biodiversity Study of Culturable Fungal Communities Inhabiting Cryoconite Holes in the Werenskiold Glacier on Spitsbergen (Svalbard Archipelago, Arctic)

Cryoconite holes on glacier surfaces are a source of cold-adapted microorganisms, but little is known about their fungal inhabitants. Here, we provide the first report of distinctive fungal communities in cryoconite holes in the Werenskiold Glacier on Spitsbergen (Svalbard Archipelago, Arctic). Due to a combination of two incubation temperatures (7 °C and 24 ± 0.5 °C) and two media during isolation (PDA, YPG), as well as classical and molecular identification approaches, we were able to identify 23 different fungi (21 species and 2 unassigned species). Most of the fungi cultured from cryoconite sediment were ascomycetous filamentous micromycetes. However, four representatives of macromycetes were also identified (Bjerkandera adusta, Holwaya mucida, Orbiliaceae sp., and Trametes versicolor). Some of the described fungi possess biotechnological potential (Aspergillus pseudoglaucus, A. sydowii, Penicillium expansum, P. velutinum, B. adusta, and T. versicolor), thus, we propose the Arctic region as a source of new strains for industrial applications. In addition, two phytopathogenic representatives were present (P. sumatraense, Botrytis cinerea), as well as one potentially harmful to humans (Cladosporium cladosporioides). To the best of our knowledge, we are the first to report the occurrence of A. pseudoglaucus, C. allicinum, C. ramotenellum, P. sumatraense, P. velutinum, P. cumulodentata, B. adusta, and T. versicolor in polar regions. In all likelihood, two unassigned fungus species (Orbiliaceae and Dothideomycetes spp.) might also be newly described in such environments. Additionally, due to experimenting with 10 sampling sites located at different latitudes, we were able to conclude that the number of fungal spores decreases as one moves down the glacier. Considering the prevalence and endangerment of glacial environments worldwide, such findings suggest their potential as reservoirs of fungal diversity, which should not be overlooked.

Fungal diversity in a sediment core from climate change impacted Boeckella Lake, Hope Bay, north-eastern Antarctic Peninsula assessed using metabarcoding

We studied the fungal DNA present in a lake sediment core obtained from Trinity Peninsula, Hope Bay, north-eastern Antarctic Peninsula, using metabarcoding through high-throughput sequencing (HTS). Sequences obtained were assigned to 146 amplicon sequence variants (ASVs) primarily representing unknown fungi, followed by the phyla Ascomycota, Rozellomycota, Basidiomycota, Chytridiomycota and Mortierellomycota. The most abundant taxa were assigned to Fungal sp., Pseudeurotium hygrophilum, Rozellomycota sp. 1, Pseudeurotiaceae sp. 1 and Chytridiomycota sp. 1. The majority of the DNA reads, representing 40 ASVs, could only be assigned at higher taxonomic levels and may represent taxa not currently included in the sequence databases consulted and/or be previously undescribed fungi. Different sections of the core were characterized by high sequence diversity, richness and moderate ecological dominance indices. The assigned diversity was dominated by cosmopolitan cold-adapted fungi, including known saprotrophic, plant and animal pathogenic and symbiotic taxa. Despite the overall dominance of Ascomycota and Basidiomycota and psychrophilic Mortierellomycota, members of the cryptic phyla Rozellomycota and Chytridiomycota were also detected in abundance. As Boeckella Lake may cease to exist in approaching decades due the effects of local climatic changes, it also an important location for the study of the impacts of these changes on Antarctic microbial diversity.

Apothecial Ancestry, Evolution, and Re-Evolution in Thelebolales (Leotiomycetes, Fungi)

Simple Summary

Leotiomycetes is one of the most speciose classes of the phylum Ascomycota (Fungi). Its species are mainly apothecioid, paraphysate, and possess active ascospore discharge. Thelebolales are a distinctive order of the Leotiomycetes class whose members have mostly closed ascomata, evanescent asci, and thus passively dispersed ascospores. Within the order, a great diversity of peridia have evolved as adaptations to different dispersal strategies. The genus Thelebolus is an exceptional case of ascomatal evolution within the order. Its species are the most diverse in functional traits, encompassing species with closed ascomata and evanescent asci, and species with open ascomata, active ascospore discharge, and paraphyses. Open ascomata were previously suggested as the ancestral state in the genus, these ascomata depend on mammals and birds as dispersal agents. In our work, we used morphological and phylogenetic methods, as well as the reconstruction of ancestral traits for ascomatal type, asci dehiscence, the presence or absence of paraphyses, and ascospore features to explore evolution within Thelebolales. We demonstrate the apothecial ancestry in Thelebolales and propose a new hypothesis about the evolution of the open ascomata in Thelebolus involving a process of re-evolution where the active dispersal of ascospores appears independently twice within the order. A new family, Holwayaceae, is proposed within Thelebolales, comprising three genera: Holwaya, Patinella, and Ramgea.

Abstract

Closed cleistothecia-like ascomata have repeatedly evolved in non-related perithecioid and apothecioid lineages of lichenized and non-lichenized Ascomycota. The evolution of a closed, darkly pigmented ascoma that protects asci and ascospores is conceived as either an adaptation to harsh environmental conditions or a specialized dispersal strategy. Species with closed ascomata have mostly lost sterile hymenial elements (paraphyses) and the capacity to actively discharge ascospores. The class Leotiomycetes, one of the most speciose classes of Ascomycota, is mainly apothecioid, paraphysate, and possesses active ascospore discharge. Lineages with closed ascomata, and their morphological variants, have evolved independently in several families, such as Erysiphaceae, Myxotrichaceae, Rutstroemiaceae, etc. Thelebolales is a distinctive order in the Leotiomycetes class. It has two widespread families (Thelebolaceae, Pseudeurotiaceae) with mostly closed ascomata, evanescent asci, and thus passively dispersed ascospores. Within the order, closed ascomata dominate and a great diversity of peridia have evolved as adaptations to different dispersal strategies. The type genus, Thelebolus, is an exceptional case of ascomatal evolution within the order. Its species are the most diverse in functional traits, encompassing species with closed ascomata and evanescent asci, and species with open ascomata, active ascospore discharge, and paraphyses. Open ascomata were previously suggested as the ancestral state in the genus, these ascomata depend on mammals and birds as dispersal agents. In this scheme, species with closed ascomata, a lack of paraphyses, and passive ascospore discharge exhibit derived traits that evolved in adaptation to cold ecosystems. Here, we used morphological and phylogenetic methods, as well as the reconstruction of ancestral traits for ascomatal type, asci dehiscence, the presence or absence of paraphyses, and ascospore features to explore evolution within Thelebolales. We demonstrate the apothecial ancestry in Thelebolales and propose a new hypothesis about the evolution of the open ascomata in Thelebolus, involving a process of re-evolution where the active dispersal of ascospores appears independently twice within the order. We propose a new family, Holwayaceae, within Thelebolales, that retains the phenotypic features exhibited by species of Thelebolus, i.e., pigmented capitate paraphyses and active asci discharge with an opening limitation ring.

Diversity, ecology, and bioprospecting of culturable fungi in lakes impacted by anthropogenic activities in Maritime Antarctica

In this study, we accessed culturable fungal assemblages present in the sediments of three lakes potentially impacted anthropogenically in the Fildes Peninsula, King George Island, Antarctica and identified 63 taxa. Cladosporium sp. 2, Pseudeurotium hygrophilum, and Pseudogymnoascus verrucosus were recovered from the sampled sediments of all lakes. High concentrations of metals and the lowest fungal diversity indices were detected in the sediments of the Central Lake, which can be influenced by human activities due to their proximity to research stations to those of the other two lakes, which were far from the Antarctic stations. At least one type of biological activity was demonstrated by 40 fungal extracts. Among these, P. hygrophilum, P. verrucosus, Penicillium glabrum, and Penicillium solitum demonstrated strong trypanocidal, herbicidal, and antifungal activities. Our results suggest that an increase of the anthropogenic activities in the region might have affected the microbial diversity and composition. In addition, the fungal diversity in these lakes may be a useful model to study the effect of anthropogenic activities in Antarctica. We isolated a diverse group of fungal taxa from Antarctic lake sediments, which have the potential to produce novel compounds for the both the medical and agriculture sectors.

Microbial diversity along a gradient in peatlands treating mining-affected waters

Peatlands are used for the purification of mining-affected waters in Northern Finland. In Northern climate, microorganisms in treatment peatlands (TPs) are affected by long and cold winters, but studies about those microorganisms are scarce. Thus, the bacterial, archaeal and fungal communities along gradients of mine water influence in two TPs were investigated. The TPs receive waters rich in contaminants, including arsenic (As), sulfate (SO42-) and nitrate (NO3-). Microbial diversity was high in both TPs, and microbial community composition differed between the studied TPs. Bacterial communities were dominated by Proteobacteria, Actinobacteria, Chloroflexi and Acidobacteria, archaeal communities were dominated by Methanomicrobia and the Candidate phylum Bathyarchaeota, and fungal communities were dominated by Ascomycota (Leotiomycetes, Dothideomycetes, Sordariomycetes). The functional potential of the bacterial and archaeal communities in TPs was predicted using PICRUSt. Sampling points affected by high concentrations of As showed higher relative abundance of predicted functions related to As resistance. Functions potentially involved in nitrogen and SO42- turnover in TPs were predicted for both TPs. The results obtained in this study indicate that (i) diverse microbial communities exist in Northern TPs, (ii) the functional potential of the peatland microorganisms is beneficial for contaminant removal in TPs and (iii) microorganisms in TPs are likely well-adapted to high contaminant concentrations as well as to the Northern climate.

Fungi in perennial ice from Scărișoara Ice Cave (Romania)

Screening of 1,000-years old ice layers from the perennial ice block of Scărișoara Ice Cave (NW Romania) revealed the presence of fungal communities. Using culture-dependent methods and molecular techniques based on DGGE fingerprinting of 18S rRNA gene fragments and sequencing, we identified 50 cultured and 14 uncultured fungi in presently-forming, 400 and 900 years old ice layers, corresponding to 28 distinct operational taxonomic units (OTUs). The dominant ice-contained fungal OTUs were related to Ascomycota, Basidiomycota and Cryptomycota phyla. Representatives of Mucoromycota and Chytridiomycota were also isolated from recent and 400 years old ice samples. The cryophilic Mrakia stokesii was the most abundant fungal species found in the cave ice samples of all prospected ages, alongside other cryophilic fungi also identified in various glacial environments. Ice deposits formed during the Little Ice Age (dated between AD 1,250 and 1,850) appeared to have a higher fungal diversity than the ice layer formed during the Medieval Warm Period (prior to AD 1,250). A more complex fungal community adapted to low temperatures was obtained from all analyzed ice layers when cultivated at 4 °C as compared to 15 °C, suggesting the dominance of cold-adapted fungi in this glacial habitat. The fungal distribution in the analyzed cave ice layers revealed the presence of unique OTUs in different aged-formed ice deposits, as a first hint for putative further identification of fungal biomarkers for climate variations in this icy habitat. This is the first report on fungi from a rock-hosted cave ice block.

Overlooked competing asexual and sexually typified generic names of Ascomycota with recommendations for their use or protection

With the change to one scientific name for fungal species, numerous papers have been published with recommendations for use or protection of competing generic names in major groups of ascomycetes. Although genera in each group of fungi were carefully considered, some competing generic names were overlooked. This paper makes recommendations for additional competing genera not considered in previous papers. Chairs of relevant Working Groups of the ICTF were consulted in the development of these recommendations. A number of generic names need protection, specifically Amarenographium over Amarenomyces, Amniculicola over Anguillospora, Balansia over Ephelis, Claviceps over Sphacelia, Drepanopeziza over Gloeosporidiella and Gloeosporium, Golovinomyces over Euoidium, Holwaya over Crinium, Hypocrella over Aschersonia, Labridella over Griphosphaerioma, Metacapnodium over Antennularia, and Neonectria over Cylindrocarpon and Heliscus. The following new combinations are made: Amniculicola longissima, Atichia maunauluana, Diaporthe columnaris, D. liquidambaris, D. longiparaphysata, D. palmicola, D. tersa, Elsinoë bucidae, E.caricae, E. choisyae, E. paeoniae, E. psidii, E. zorniae, Eupelte shoemakeri, Godronia myrtilli, G. raduloides, Sarcinella mirabilis, S. pulchra, Schizothyrium jamaicense, and Trichothallus niger. Finally, one new species name, Diaporthe azadirachte, is introduced to validate an earlier name, and the conservation of Discula with a new type, D. destructiva, is recommended.

Psychrophilic and psychrotolerant fungi on bats and the presence of Geomyces spp. on bat wings prior to the arrival of white nose syndrome

Since 2006, Geomyces destructans, the causative agent of white nose syndrome (WNS), has killed over 5.7 million bats in North America. The current hypothesis suggests that this novel fungus is an invasive species from Europe, but little is known about the diversity within the genus Geomyces and its distribution on bats in the United States. We documented the psychrophilic and psychrotolerant fungal flora of hibernating bats prior to the arrival of WNS using culture-based techniques. A total of 149 cultures, which were obtained from 30 bats in five bat hibernacula located in four caves and one mine, were sequenced for the entire internal transcribed spacer (ITS) nuclear ribosomal DNA (nrDNA) region. Approximately 53 operational taxonomic units (OTUs) at 97% similarity were recovered from bat wings, with the community dominated by fungi within the genera Cladosporium, Fusarium, Geomyces, Mortierella, Penicillium, and Trichosporon. Eleven Geomyces isolates were obtained and placed in at least seven distinct Geomyces clades based on maximum-likelihood phylogenetic analyses. Temperature experiments revealed that all Geomyces strains isolated are psychrotolerant, unlike G. destructans, which is a true psychrophile. Our results confirm that a large diversity of fungi, including several Geomyces isolates, occurs on bats prior to the arrival of WNS. Most of these isolates were obtained from damaged wings. Additional studies need to be conducted to determine potential ecological roles of these abundant Geomyces strains isolated from bats.

Responses of aerobic microbial communities and soil respiration to water-level drawdown in a northern boreal fen

On a global basis, peatlands are a major reserve of carbon (C). Hydrological changes can affect the decomposition processes in peatlands and in turn can alter their C balance. Since 1959, a groundwater extraction plant has generated a water-level gradient at our study site that has gradually changed part of the wet fen into a dry peatland forest. The average water-level drawdown of the gradient (from a pristine 9 cm to 26 cm in the dry end) is close to an estimate predicted by an increase in mean global temperature of 3 degrees C. We studied the total microbial community of the aerobic surface peat in four locations along the gradient through phospholipid fatty acid and PCR-DGGE methods. Additionally, field measurements of soil respiration showed a threefold increase in the C-emission rate at the driest location compared with the wettest one, indicating enhanced decomposition. Also, both fungal and bacterial biomass increased in the drier locations. At the species level, the fungal community changed due to water-level drawdown whereas actinobacteria were less sensitive to drying. The majority of fungal sequences were similar to ectomycorrhizal (ECM) fungi, which dominated throughout the gradient. Our results indicate that ECM fungi might act as important facultative decomposers in organic-rich environments such as peatlands.