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Mycena s.s. is a ubiquitous mushroom genus whose members degrade multiple dead plant substrates and opportunistically invade living plant roots. Having sequenced the nuclear genomes of 24 Mycena species, we find them to defy the expected patterns for fungi based on both their traditionally perceived saprotrophic ecology and substrate specializations. Mycena displayed massive genome expansions overall affecting all gene families, driven by novel gene family emergence, gene duplications, enlarged secretomes encoding polysaccharide degradation enzymes, transposable element (TE) proliferation, and horizontal gene transfers. Mainly due to TE proliferation, Arctic Mycena species display genomes of up to 502 Mbp (2-8× the temperate Mycena), the largest among mushroom-forming Agaricomycetes, indicating a possible evolutionary convergence to genomic expansions sometimes seen in Arctic plants. Overall, Mycena show highly unusual, varied mosaic-like genomic structures adaptable to multiple lifestyles, providing genomic illustration for the growing realization that fungal niche adaptations can be far more fluid than traditionally believed.

Summary: The genomes of ectomycorrhizal (ECM) fungi have a reduced number of genes encoding Carbohydrate‐Active EnZymes (CAZymes), expansions in transposable elements (TEs) and small secreted proteins (SSPs) compared with saprotrophs. Fewer genes for specific peptidases and lipases in ECM fungi are also reported. It is unclear whether these changes occur at the shift to the ECM habit or are more gradual throughout the evolution of ECM lineages.We generated a genomic dataset of 20 species in the ECM lineage Inocybaceae and compared them with six saprotrophic species.Inocybaceae genomes have fewer CAZymes, peptidases, lipases, secondary metabolite clusters and SSPs and higher TE content than their saprotrophic relatives. There was an increase in the rate of gene family evolution along the branch with the transition to the ECM lifestyle. This branch had very high rate of evolution in CAZymes and had the largest number of contractions. Other significant changes along this branch included expansions in transporters, transposons‐related genes and communication genes such as fungal kinases.There is a high concentration of changes in proximity to the transition to the ECM lifestyle, which correspond to the identified key changes for the gain of this lifestyle. [ABSTRACT FROM AUTHOR]

Crepidotus is a genus of common saprotrophic fungi well known especially in the Northern Hemisphere, but distribution patterns of individual species are not sufficiently understood. We redefined a taxonomic circumscription of Crepidotus cinnamomeus based on morphological and molecular congruencies between the type material and recent collections. The species is well delimited from other similar and currently accepted species of the genus. Crepidotus cinnamomeus was found to have a broad holarctic distribution with occurrences in North America, Europe and Asia where it grows on twigs and branches of deciduous trees and shrubs in preferably cold humid habitats. Here we present the first multilocus phylogeny of the genus, including portions of the RPB2 gene. Our study highlights the importance of sufficient sampling from broader areas supported by sequence data, which is essential for estimation of species delimitation, distribution and correct name assignment for Crepidotus species. [ABSTRACT FROM AUTHOR]

Differences between arbuscular (AM) and ectomycorrhizal (EcM) trees strongly influence forest ecosystem processes, in part through their impact on saprotrophic fungal communities. Ericoid mycorrhizal (ErM) shrubs likely also impact saprotrophic communities given that they can shape nutrient cycling by slowing decomposition rates and intensifying nitrogen limitation. We investigated the depth distributions of saprotrophic and EcM fungal communities in paired subplots with and without a common understory ErM shrub, mountain laurel (Kalmia latifolia L.), across an AM to EcM tree dominance gradient in a temperate forest by analyzing soils from the organic, upper mineral (0–10 cm), and lower mineral (cumulative depth of 30 cm) horizons. The presence of K. latifolia was strongly associated with the taxonomic and functional composition of saprotrophic and EcM communities. Saprotrophic richness was consistently lower in the Oa horizon when this ErM shrub species was present. However, in AM tree-dominated plots, the presence of the ErM shrub was associated with a higher relative abundance of saprotrophs. Given that EcM trees suppress both the diversity and relative abundance of saprotrophic communities, our results suggest that separate consideration of ErM shrubs and EcM trees may be necessary when assessing the impacts of plant mycorrhizal associations on belowground communities. [ABSTRACT FROM AUTHOR]

By incubating the soil without living roots in situ at two spruce forest sites, we simulated the effects of tree dieback and interrupted mycorrhizal associations following forest disturbance on the soil microbiome and phosphorus leaching. We observed the retreat of ectomycorrhizal fungi and increased proportion of saprotrophs without changes in community richness and the Shannon diversity index. This was accompanied by a pronounced decomposition of organic matter, associated with an increased activity of carbon-mining hydrolases and acid phosphatase. The nonexistent phosphorus uptake and immobilization by ectomycorrhizal associations led to its substantial increase in the soil, in the labile fractions, such as microbial biomass and water-soluble reactive phosphorus, but also in the fraction bound to organometallics (extractable by oxalate), and caused considerable phosphate leaching, as estimated using ion-exchange resin traps. The results show that the retreat of the root-specific environment, characterized by the input of available carbon and effective nutrient uptake and by the specific microbiome, has profound effects on phosphorus dynamics and loss. Furthermore, we suggest that ectomycorrhiza plays an equally important role in controlling phosphorus-mining from organic matter and subsequent immobilization and/or leaching from soils concurrently to its known role in nitrogen cycling and immobilization in spruce forests. [ABSTRACT FROM AUTHOR]

Stictidaceae is characterised by a wide geographic distribution and diverse ecological roles. It has recently been the focus of taxonomic research in China. In this study, we describe two new asexual Stictidaceae species that we presume to be saprobes: Glomerobolus poacearum and Ostropomyces yunnanensis. The specimens were collected from decaying stems of unidentified herbaceous and Poaceae hosts in the Yunnan Dashanbao Black-necked Crane National Nature Reserve, China. Our approach combines morphological and multi-locus phylogenetic analysis, utilising LSU, ITS, mtSSU and rpb2 markers. Glomerobolus poacearum sp. nov., was collected on decayed aquatic grass stems. In our phylogeny, it forms a well-supported clade with G. gelineus, the type of the genus. The species differs from G. gelineus in having comparatively smaller hyphoma, lobes and ballistic propagules that are spherical or fan-shaped when swollen. The discovery of Glomerobolus poacearum on Poaceae species within China are new observations of plant associates and geographical distribution in the genus. Ostropomyces yunnanensis sp. nov., was collected on a stem of a herbaceous plant. In our phylogenetic analysis, it forms a well-supported clade with G. gelineus, the type species of the genus and is characterised by the production of conidiomata with forcible discharge. Ostropomyces yunnanensis is distinguishable from the asexual morph of O. pruinosellus by possessing larger pycnidial conidiomata, which feature multiple locules of conical or irregular shapes and by having larger conidia that are 0–4-septate. These taxonomic contributions enrich our understanding of the diversity, evolutionary relationships and ecological interactions within Stictidaceae. [ABSTRACT FROM AUTHOR]

The first genome sequenced of a eukaryotic organism was for Saccharomyces cerevisiae, as reported in 1996, but it was more than 10 years before any of the zygomycete fungi, which are the early-diverging terrestrial fungi currently placed in the phyla Mucoromycota and Zoopagomycota, were sequenced. The genome for Rhizopus delemar was completed in 2008; currently, more than 1000 zygomycete genomes have been sequenced. Genomic data from these early-diverging terrestrial fungi revealed deep phylogenetic separation of the two major clades-primarily plant-associated saprotrophic and mycorrhizal Mucoromycota versus the primarily mycoparasitic or animal-associated parasites and commensals in the Zoopagomycota. Genomic studies provide many valuable insights into how these fungi evolved in response to the challenges of living on land, including adaptations to sensing light and gravity, development of hyphal growth, and co-existence with the first terrestrial plants. Genome sequence data have facilitated studies of genome architecture, including a history of genome duplications and horizontal gene transfer events, distribution and organization of mating type loci, rDNA genes and transposable elements, methylation processes, and genes useful for various industrial applications. Pathogenicity genes and specialized secondary metabolites have also been detected in soil saprobes and pathogenic fungi. Novel endosymbiotic bacteria and viruses have been discovered during several zygomycete genome projects. Overall, genomic information has helped to resolve a plethora of research questions, from the placement of zygomycetes on the evolutionary tree of life and in natural ecosystems, to the applied biotechnological and medical questions.

Rapid increase in desertification is an environmental concern, especially for the health and sustainability of ecosystems in changing climates. How ecosystems respond to such changes may be partially understood by studying interactions and performance of critically important groups such as soil fungi functional groups. This study investigated variations in diversities of three soil fungi functional guilds (saprotrophic, symbiotic, pathogenic) and influencing abiotic factors in a Pinus densata forest on the southeast Tibetan Plateau where desertification is intense. The results indicate desertification significantly decreased the proportion of dominant fungal guild-symbiotic fungi (mean relative abundance decreasing from 97.0% to 68.3%), in contrast to saprotrophic fungi (increasing from 2.7% to 25.7%) and pathogenic (from 0.3% to 5.9%). Soil pH had the most significant impact on fungal community structure and negatively correlated with symbiotic fungal richness, which was significantly lower in arid soils, and positively correlated with saprotrophic and pathogenic fungal alpha-diversity, which were abundant. Different community structures and regulators of the three fungi communities were observed, with pH, total phosphorus and ammonium (NH4+) as the main determinants. This study links the biotic and abiotic components during desertification and the interactions between them, and may be used as indicators of ecosystem health and for amendments to mitigate the effects of a changing climate. [ABSTRACT FROM AUTHOR]

By incubating the soil without living roots in situ at two spruce forest sites, we simulated the effects of tree dieback and interrupted mycorrhizal associations following forest disturbance on the soil microbiome and phosphorus leaching. We observed the retreat of ectomycorrhizal fungi and increased proportion of saprotrophs without changes in community richness and the Shannon diversity index. This was accompanied by a pronounced decomposition of organic matter, associated with an increased activity of carbon-mining hydrolases and acid phosphatase. The nonexistent phosphorus uptake and immobilization by ectomycorrhizal associations led to its substantial increase in the soil, in the labile fractions, such as microbial biomass and water-soluble reactive phosphorus, but also in the fraction bound to organometallics (extractable by oxalate), and caused considerable phosphate leaching, as estimated using ion-exchange resin traps. The results show that the retreat of the root-specific environment, characterized by the input of available carbon and effective nutrient uptake and by the specific microbiome, has profound effects on phosphorus dynamics and loss. Furthermore, we suggest that ectomycorrhiza plays an equally important role in controlling phosphorus-mining from organic matter and subsequent immobilization and/or leaching from soils concurrently to its known role in nitrogen cycling and immobilization in spruce forests.

Simple Summary: The fungi community has received comparatively little attention compared to bacteria in previous studies on the avian gut microbiome. Even though fungi constitute a smaller proportion of the gastrointestinal (GIT) microbiota, changes in the diversity and composition of the gut microbial population have been associated with a number of diseases. This study, concentrating on captive migratory ducks, provides light on the gut fungal population, identifies potential animal pathogens and plant saprotrophs, and reveals that seasonal variations shape the dynamics of the gut fungal community more significantly than the host species. Understanding the dynamics of avian gut fungal communities and potentially pathogenic species across different seasons is crucial for assessing their health and ecological interactions. In this study, high-throughput sequencing was employed to examine the changes in gut fungal communities and the presence of potential pathogens between different seasons in captive Baikal teal and common teal. Between the summer and autumn seasons, both duck species showed significant differences in fungal diversity and community composition. A higher fungal diversity in both species was exhibited in the summer than in the autumn. Ascomycota and Basidiomycota were the two most common phyla, with a greater proportion of Ascomycota than Basidiomycota in both duck species in the summer. Interestingly, our study also identified animal pathogens and plant saprotrophs in the gut fungal communities. Seasonal variation had an effect on the diversity and abundance of both animal pathogens and saprotrophs. Specifically, during the summer season, the diversity and relative abundance were higher compared to the autumn season. In addition, there were differences between duck species in terms of animal pathogens, while no significant differences were observed in saprotrophs. Overall, the communities of the gut fungi, animal pathogens, and saprotrophs were found to be influenced by seasonal changes rather than host species. Therefore, seasonal variations might dominate over host genetics in shaping the gut microbiota of captive Baikal teal and common teal. This study underscores the importance of incorporating an understanding of seasonal dynamics and potential pathogens within the gut microbiota of captive ducks. Such considerations have the potential to drive progress in the development of sustainable and economically viable farming practices. [ABSTRACT FROM AUTHOR]

Labyrinthulomycetes are a small but very important group of marine fungi-like organisms. Labyrinthulomycetes are ubiquitous, can be associated with living plants, algae, and animals, and can decompose a variety of organic remains. These organisms are able to synthesize and abundantly accumulate lipids, in particular, polyunsaturated fatty acids, some of which are of great interest for biotechnology. The scientific information about labyrinthulomycetes is currently accumulating very quickly. Our study is devoted to reviewing the presently available data on the structure, biology, and taxonomy of these organisms. This review examines the problems of methodological approaches to the study of these organisms, as well as the diversity, distribution, and significance of Labyrinthulomycetes in marine ecosystems. [ABSTRACT FROM AUTHOR]

Prunus serotina is an important invasive plant species in Poland. It was introduced to European forests, even in places currently protected by law, such as national parks. One major factor contributing to the spread of this species is the lack of infecting pathogens and incomplete knowledge about the relationship between the plant and microorganisms. This study aimed to identify fungal communities collected from freshly cut stumps of live and dead black cherry tree specimens growing in a protected forest. The main working hypotheses were as follows: (i) fungal communities inhabiting the wood of dead and living trees will differ in diversity and the number of taxa; and (ii) saprotrophic fungi will dominate in the wood of dead tree stumps. This study applied Illumina sequencing based on the amplification of the fungal ribosomal ITSI region. The average number of sequences (OTU) obtained from the analysis of dead tree wood was 101,758, while that of living trees was 94,150. These sequences belonged to 312 taxa, among which 254 were isolated from the wood of dead trees and 171 from that of living trees. Among the saprotrophs on dead trees, the following species were identified: Stereum rugosum, Ganoderma adspersum, G. applanatum, Peniophora cinerea, and Ascocoryne cylichnium. On the other hand, in the wood of living trees, Cytospora leucostoma and Botrytis cinerea were the most abundant saprotrophic species. The fungal communities inhabiting the wood of dead and living trees differed in the diversity and abundance of taxa, thus confirming our hypothesis. The results of our research conducted in a protected area indicate that black cherry wood can be naturally colonized by many pathogen species that can further limit its expansion. [ABSTRACT FROM AUTHOR]

The secretory proteome plays an important role in the pathogenesis of phytopathogenic fungi. However, the relationship between the large-scale secretome of phytopathogenic fungi and their lifestyle is not fully understood. In the present study, the secretomes of 150 plant pathogenic fungi were predicted and the characteristics associated with different lifestyles were investigated. In total, 94,974 secreted proteins (SPs) were predicted from these fungi. The number of the SPs ranged from 64 to 1,662. Among these fungi, hemibiotrophic fungi had the highest number (average of 970) and proportion (7.1%) of SPs. Functional annotation showed that hemibiotrophic and necrotroph fungi, differ from biotrophic and symbiotic fungi, contained much more carbohydrate enzymes, especially polysaccharide lyases and carbohydrate esterases. Furthermore, the core and lifestyle-specific SPs orthogroups were identified. Twenty-seven core orthogroups contained 16% of the total SPs and their motif function annotation was represented by serine carboxypeptidase, carboxylesterase and asparaginase. In contrast, 97 lifestyle-specific orthogroups contained only 1% of the total SPs, with diverse functions such as PAN_AP in hemibiotroph-specific and flavin monooxygenases in necrotroph-specific. Moreover, obligate biotrophic fungi had the largest number of effectors (average of 150), followed by hemibiotrophic fungi (average of 120). Among these effectors, 4,155 had known functional annotation and pectin lyase had the highest proportion in the functionally annotated effectors. In addition, 32 sets of RNA-Seq data on pathogen-host interactions were collected and the expression levels of SPs were higher than that of non-SPs, and the expression level of effector genes was higher in biotrophic and hemibiotrophic fungi than in necrotrophic fungi, while secretase genes were highly expressed in necrotrophic fungi. Finally, the secretory activity of five predicted SPs from Setosphearia turcica was experimentally verified. In conclusion, our results provide a foundation for the study of pathogen-host interaction and help us to understand the fungal lifestyle adaptation. [ABSTRACT FROM AUTHOR]

Background: Mycetoma also synonymous referred to as Madura's foot is a chronic granulomatous cutaneous infection caused by some genera of fungi and bacteria, leading to progressive and proliferative destruction of soft tissue and the nearby anatomical structures if no intervention is offered on time. Case presentation: We report a case of actinomycetoma in an African adult man residing in a rural-urban setup. After histological confirmation, the client was conservatively managed with oral medication: 1) dapsone 100mg once a day and t r ime thopr im/sul f ame thoxa zol e (s ept r in) 160mg/800mg three times daily for one year with an excellent outcome. Conclusions: The gist of this rare case is to exemplify the role of integrated management of patients without underplaying the role of good clinical practice. Also, a call and advocate for improved health care services in the sub-Saharan countries. This will prevent or reduce avoidable medical complications caused by neglected and treatable diseases like actinomycocetoma. [ABSTRACT FROM AUTHOR]

The western red cedar (Thuja plicata Donn ex D. Don), an important forest-forming species in the Western part of the North American continent, is an alien species naturalised in Europe. It is popular and highly valued in horticulture. While considering the progressing climate change, it may also be a potential alternative to native species in European forests. The community of soil fungi associated with the western red cedar in forested areas of Europe has not been fully determined. Thus, this study is aimed to identify the community of soil fungi associated with the western red cedar. The experimental plots are located in the Kościan Forest District (51°98'87″ N; 16°23'54″ E). All soil samples were taken from the topsoil layer at a depth of 25 cm with a trowel, three from the centre of natural regeneration (1G, 2G, 5G) and three from the centre stand under the canopy of old-growth western red cedar (3G, 4G, 6G). Fungi were identified directly from the soil based on the ITS1 rDNA region. The derived product was sequenced using Illumina's sequencing by synthesis (SBS) technology. Sequences were referred to the National Center for Biotechnology Information (NCBI) database applying the BLAST algorithm. The fungal counts were defined based on the number of operational taxonomic units (OTU) in the sample. The OTU number was 835 206, with fungal isolates accounting for 683 095 (81.79%). A total of 8 591 taxa belonging to the Kingdom Fungi were identified. The species with the greatest shares in the community included Mortierella spp. (10.5%), Russula spp. (5.6%), Hydnum spp. (3.44%), Solicoccozyma spp. (3.1%) and Penicillium spp. (2.2%). Results showed that saprotrophs and mycorrhizal fungi predominated in the community. The dominance of ectomycorrhizal fungi over arbuscular ones, quite impressive natural regeneration was shown in T. plicata stands in Kościan. Subsequent research should take into account tree stands in Poland in which natural regeneration does not occur or occurs sporadically. [ABSTRACT FROM AUTHOR]

Recently, a new annotation tool "FungalTraits" was created based on the previous FUNGuild and FunFun databases, which has attracted high attention in the scientific community. These databases were widely used to gain more information from fungal sequencing datasets by assigning fungal functional traits. More than 1500 publications so far employed FUNGuild and the aim of this study is to compare this successful database with the recent FungalTraits database. Quality and quantity of the assignment by FUNGuild and FungalTraits to a fungal internal transcribed spacer (ITS)–based amplicon sequencing dataset on amplicon sequence variants (ASVs) were addressed. Sequencing dataset was derived from leaves and needles of 12 temperate broadleaved and coniferous tree species. We found that FungalTraits assigned more functional traits than FUNGuild, and especially the coverage of saprotrophs, plant pathogens, and endophytes was higher while lichenized fungi revealed similar findings. Moreover, ASVs derived from leaves and needles of each tree species were better assigned to all available fungal traits as well as to saprotrophs by FungalTraits compared to FUNGuild in particular for broadleaved tree species. Assigned ASV richness as well as fungal functional community composition was higher and more diverse after analyses with FungalTraits compared to FUNGuild. Moreover, datasets of both databases showed similar effect of environmental factors for saprotrophs but for endophytes, unidentical patterns of significant corresponding factors were obtained. As a conclusion, FungalTraits is superior to FUNGuild in assigning a higher quantity and quality of ASVs as well as a higher frequency of significant correlations with environmental factors. [ABSTRACT FROM AUTHOR]

Understanding the dynamics of avian gut fungal communities and potentially pathogenic species across different seasons is crucial for assessing their health and ecological interactions. In this study, high-throughput sequencing was employed to examine the changes in gut fungal communities and the presence of potential pathogens between different seasons in captive Baikal teal and common teal. Between the summer and autumn seasons, both duck species showed significant differences in fungal diversity and community composition. A higher fungal diversity in both species was exhibited in the summer than in the autumn. Ascomycota and Basidiomycota were the two most common phyla, with a greater proportion of Ascomycota than Basidiomycota in both duck species in the summer. Interestingly, our study also identified animal pathogens and plant saprotrophs in the gut fungal communities. Seasonal variation had an effect on the diversity and abundance of both animal pathogens and saprotrophs. Specifically, during the summer season, the diversity and relative abundance were higher compared to the autumn season. In addition, there were differences between duck species in terms of animal pathogens, while no significant differences were observed in saprotrophs. Overall, the communities of the gut fungi, animal pathogens, and saprotrophs were found to be influenced by seasonal changes rather than host species. Therefore, seasonal variations might dominate over host genetics in shaping the gut microbiota of captive Baikal teal and common teal. This study underscores the importance of incorporating an understanding of seasonal dynamics and potential pathogens within the gut microbiota of captive ducks. Such considerations have the potential to drive progress in the development of sustainable and economically viable farming practices.

Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high‐resolution, long‐read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West‐Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land‐cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early‐diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms. [ABSTRACT FROM AUTHOR]

Summary: Mycorrhizal fungi associated with boreal trees and ericaceous shrubs are central actors in organic matter (OM) accumulation through their belowground carbon allocation, their potential capacity to mine organic matter for nitrogen (N) and their ability to suppress saprotrophs. Yet, interactions between co‐occurring ectomycorrhizal fungi (EMF), ericoid mycorrhizal fungi (ERI), and saprotrophs are poorly understood.We used a long‐term (19 yr) plant functional group manipulation experiment with removals of tree roots, ericaceous shrubs and mosses and analysed the responses of different fungal guilds (assessed by metabarcoding) and their interactions in relation to OM quality (assessed by mid‐infrared spectroscopy and nuclear magnetic resonance) and decomposition (litter mesh‐bags) across a 5000‐yr post‐fire boreal forest chronosequence.We found that the removal of ericaceous shrubs and associated ERI changed the composition of EMF communities, with larger effects occurring at earlier stages of the chronosequence. Removal of shrubs was associated with enhanced N availability, litter decomposition and enrichment of the recalcitrant OM fraction.We conclude that increasing abundance of slow‐growing ericaceous shrubs and the associated fungi contributes to increasing nutrient limitation, impaired decomposition and progressive OM accumulation in boreal forests, particularly towards later successional stages. These results are indicative of the contrasting roles of EMF and ERI in regulating belowground OM storage. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) play an important role on litter decomposition, which is the keyways for nutrients returning to natural ecosystems. Although having no known saprotrophic abilities like ectomycorizal and ericoid fungi, AMF can affect litter decomposition by releasing low molecular compounds such as sugar, amino acids and organic acids through extraradical mycorrhizal hyphae, or deposit dead hypha fragments as nutrient (e.g., carbon) input and to stimulate microbial decomposers, i.e., priming effect. Besides, interactions of AMF with saprotrophic microorganisms through ways such as niche competition, synergistic cooperation, specific microorganisms recruitment and by soil nutrient removal that can influence litter decomposition. Under different microenvironments, AMF display various nutrient acquisition strategies, which also affects this process. The magnitude and direction of AMF effects on litter decomposition depend on plant communities, litter quality, soil and litter nutrient dynamics, soil physical and chemical properties (mainly, physical structure, temperature, humidity, pH and nutrient content). The exacerbation of global changes (drought, chemical fertilization and soil acidification) is exerting pervasive impacts on ecosystem processes and functions mediated by AMF. In this review, we explore the current state of knowledge about the impacts of AMF on litter decomposition from microenvironment perspective. The summary of the potential influence of various microsite abiotic and biotic factors on this process in order to provide theoretical reference for comprehensive analysis of ecosystem functions of AMF is made. [ABSTRACT FROM AUTHOR]

Aim: To uncover the biogeography of non‐native macrofungal diversity worldwide, by analysing patterns and drivers of (1) regional variation in species richness, (2) compositional similarity between regional species assemblages and (3) the spatiotemporal trends of first records. Location: Global. Methods: We used a database providing 1608 distribution records of 554 non‐native macrofungal species in 167 national and sub‐national regions worldwide. Regression models accounting for regional levels of recording capacity were used to relate spatial variation of non‐native macrofungal richness and of regional compositional similarities to variables representing geographical, socio‐economic and biophysical characteristics of regions. Temporal trends of first records were assessed at the global and continental scales and for distinct ecofunctional groups. Results: Regions reporting higher diversity of non‐native species occur mainly in Europe, the Americas and Oceania. Regression models showed that regions with greater gross domestic product per capita, areal extent and in the Southern Hemisphere have higher non‐native species richness, while regions with similar mean temperatures and latitudinal position share higher compositional similarities. Numbers of first records of non‐native macrofungi have grown quasi‐exponentially between 1753 and 2018, reflecting not only improved recording capacities but also likely an increasing number of introductions. Main Conclusions: We find that many regions of the world already harbour a high diversity of non‐native macrofungi, with economic, climatic and introduction pathway‐related factors explaining a relevant portion of the geographical patterns formed by these taxa. Given that socio‐economic activity has increased strongly in recent decades, the global anthropogenic redistribution of macrofungi is likely to intensify further in the near future. [ABSTRACT FROM AUTHOR]

Summary: Ericoid mycorrhizal (ErM) shrubs commonly occur in forest understories and could therefore alter arbuscular (AM) and/or ectomycorrhizal (EcM) tree effects on soil carbon and nitrogen dynamics. Specifically, ErM fungi have extensive organic matter decay capabilities, and ErM plant and fungal tissues have high concentrations of secondary compounds that can form persistent complexes in the soil. Together, these traits could contribute to organic matter accumulation and inorganic nutrient limitation. These effects could also differ in AM‐ vs EcM‐dominated stands at multiple scales within and among forest biomes by, for instance, altering fungal guild interactions. Most work on ErM effects in forests has been conducted in boreal forests dominated by EcM trees. However, ErM plants occur in c. 96, 69 and 29% of boreal, temperate and tropical forests, respectively. Within tropical montane forests, the effects of ErM plants could be particularly pronounced because their traits are more distinct from AM than EcM trees. Because ErM fungi can function as free‐living saprotrophs, they could also be more resilient to forest disturbances than obligate symbionts. Further consideration of ErM effects within and among forest biomes could improve our understanding of how cooccurring mycorrhizal types interact to collectively affect soil carbon and nitrogen dynamics under changing conditions. [ABSTRACT FROM AUTHOR]

Mycocaliciales comprise non-lichenized either saprotrophic or lichenicolous fungi which occur in temperate and tropical regions. The mazaediate, saprotrophic and monospecific genus, Pyrgidium, is currently assigned to this order, yet the phylogenetic placement of the genus has remained uncertain due to the absence of molecular data. In order to investigate the systematic position of Pyrgidium, two specimens collected in Brazil and Thailand, respectively, were used to generate mtSSU, SSU, LSU and ITS sequences. However, given that most other representatives of this order only have LSU and ITS sequences available, the phylogenetic reconstruction was limited to these two markers. The phylogenetic analyses confirmed placement of the genus within Mycocaliciales, the genus possessing a sister group relationship with the lichenicolous genus Sphinctrina. Detailed morphological descriptions and illustrations are provided, including those for type specimens of the various synonyms subsumed under the hitherto only accepted species, Pyrgidium montellicum (Beltr.) Tibell. The ascospore morphology was investigated using compound and scanning electronic microscopy (SEM). Principal component analysis (PCA) was performed for the ascospore size using PC-ORD 7. The molecular data and re-examination of the type specimens support the monospecific nature of this genus. [ABSTRACT FROM AUTHOR]

The first genome sequenced of a eukaryotic organism was for Saccharomyces cerevisiae, as reported in 1996, but it was more than 10 years before any of the zygomycete fungi, which are the early-diverging terrestrial fungi currently placed in the phyla Mucoromycota and Zoopagomycota, were sequenced. The genome for Rhizopus delemar was completed in 2008; currently, more than 1000 zygomycete genomes have been sequenced. Genomic data from these early-diverging terrestrial fungi revealed deep phylogenetic separation of the two major clades—primarily plant—associated saprotrophic and mycorrhizal Mucoromycota versus the primarily mycoparasitic or animal-associated parasites and commensals in the Zoopagomycota. Genomic studies provide many valuable insights into how these fungi evolved in response to the challenges of living on land, including adaptations to sensing light and gravity, development of hyphal growth, and co-existence with the first terrestrial plants. Genome sequence data have facilitated studies of genome architecture, including a history of genome duplications and horizontal gene transfer events, distribution and organization of mating type loci, rDNA genes and transposable elements, methylation processes, and genes useful for various industrial applications. Pathogenicity genes and specialized secondary metabolites have also been detected in soil saprobes and pathogenic fungi. Novel endosymbiotic bacteria and viruses have been discovered during several zygomycete genome projects. Overall, genomic information has helped to resolve a plethora of research questions, from the placement of zygomycetes on the evolutionary tree of life and in natural ecosystems, to the applied biotechnological and medical questions.

Prunus serotina is an important invasive plant species in Poland. It was introduced to European forests, even in places currently protected by law, such as national parks. One major factor contributing to the spread of this species is the lack of infecting pathogens and incomplete knowledge about the relationship between the plant and microorganisms. This study aimed to identify fungal communities collected from freshly cut stumps of live and dead black cherry tree specimens growing in a protected forest. The main working hypotheses were as follows: (i) fungal communities inhabiting the wood of dead and living trees will differ in diversity and the number of taxa; and (ii) saprotrophic fungi will dominate in the wood of dead tree stumps. This study applied Illumina sequencing based on the amplification of the fungal ribosomal ITSI region. The average number of sequences (OTU) obtained from the analysis of dead tree wood was 101,758, while that of living trees was 94,150. These sequences belonged to 312 taxa, among which 254 were isolated from the wood of dead trees and 171 from that of living trees. Among the saprotrophs on dead trees, the following species were identified: Stereum rugosum, Ganoderma adspersum, G. applanatum, Peniophora cinerea, and Ascocoryne cylichnium. On the other hand, in the wood of living trees, Cytospora leucostoma and Botrytis cinerea were the most abundant saprotrophic species. The fungal communities inhabiting the wood of dead and living trees differed in the diversity and abundance of taxa, thus confirming our hypothesis. The results of our research conducted in a protected area indicate that black cherry wood can be naturally colonized by many pathogen species that can further limit its expansion.

Understanding soil dynamics and nutrient cycling is crucial for the sustainable management of Japanese forests covering 70 % of the national land area. These forests are dominated by tree species with contrasting traits, influencing soil dynamics differently. We investigated how changes in soil characteristics across different forest stands shift in composition and functioning of fungal communities. Four different forest stands dominated by two different mycorrhizal types were selected: Fagus crenata and Larix kaempferi, representing ectomycorrhizal (ECM) types, and Cryptomeria japonica and Robinia pseudoacacia, representing arbuscular mycorrhizal (AM) types. In total, 62 composite topsoil samples from two depths were analyzed for their physicochemical properties and fungal communities were profiled by DNA sequencing. Ectomycorrhizal fungi dominated soils of Fagus crenata and Larix kaempferi forests, while fungal saprotrophs were more abundant in Cryptomeria japonica and Robinia pseudoacacia forests. Forest stand type rather than soil depth determined the composition and structure of soil fungal communities. Soil pH was positively correlated with abundances of saprotrophic fungi (P < 0.05) and negatively with ECM fungi. Soil C:N ratio was positively correlated, and nitrate was negatively correlated with relative abundances of root-associated fungi, primarily ECM fungi. No links between C nor N stocks with fungal guilds were found across the dataset. Observed links between soil C:N ratio and relative abundances of root-associated fungi and saprotrophs stress the importance of these guilds for influencing nutrient cycling economy across contrasting forest types. The lack of correlation between fungal communities and soil C and N stocks suggests distinct mechanisms driving stocks in these soils. [Display omitted] • Soil pH, nitrate and C:N correlate with fungal community composition and structure • Soil C:N positively correlated with relative abundances of root-associated fungi • Nitrate negatively correlated with relative abundances of root-associated fungi • No links between C nor N stocks with fungal guilds were found • Links between soil C:N and fungal community influence nutrient cycling economy [ABSTRACT FROM AUTHOR]

The AMF and saprotroph studies only considered abiotic niche axes (soil chemistry and climate), whereas the plant pathogen analysis used one biotic axis (host range) and one abiotic condition (temperature). For plant pathogens and saprotrophs, temperature and moisture niches for growth in culture were quantified experimentally and can be considered estimates of the fundamental niche. Arbuscular mycorrhizal fungi, fungi, niche breadth, niche width, plant pathogens, saprotrophs Keywords: arbuscular mycorrhizal fungi; fungi; niche breadth; niche width; plant pathogens; saprotrophs EN arbuscular mycorrhizal fungi fungi niche breadth niche width plant pathogens saprotrophs 345 349 5 03/22/22 20220415 NES 220415 Acknowledgements TMC was funded by a BBSRC SWBio Doctoral Training Award. [Extracted from the article]

We investigated fungal communities colonising black cherry stumps. We tested the hypothesis that black cherry stumps of greater diameter should be characterised by more diverse fungal communities than stumps of smaller diameter. The material for analyses came from Podanin Forest District. DNA was extracted using a Plant Genomic DNA purification kit. The results were subjected to bioinformatic analysis and statistical analysis. The OTU sequences were compared using the BLAST algorithm with reference sequences from the UNITE database. In total, 8192 raw sequences were obtained from samples of black cherry stumps applying the Illumina sequencing technique. The results of the statistical analysis indicate a trend towards increased diversity in bigger black cherry stumps. The dominant share of fungi associated with wood decomposition indicates the progressing process of decomposition in stumps. Identification of the role and functions of the individual components of fungal communities colonising stumps may provide insight into the overall ecology of these organisms and provide a basis for improved plant protection, with a view to limiting the occurrence of black cherries in the future in undesirable locations outside their natural range.

Fungi produce a variety of extracellular enzymes, making recalcitrant substrates bioavailable. Thus, fungi are central for the decomposition of dead organic matter such as leaf litter. Despite their ecological importance, our understanding of relationships between fungal species diversity and ecosystem functioning is limited, especially with regard to aquatic habitats. Moreover, fungal interactions with other groups of microorganisms such as bacteria are rarely investigated. This lack of information may be attributed to methodological limitations in tracking the biomass of individual fungal species in communities, impeding a detailed assessment of deviations from the overall performance expected from the sum of individual species' performances, so‐called net diversity effects (NDEs). We used fungal species‐specific biomolecular tools to target fungal–fungal and fungal–bacterial interactions on submerged leaves using four cosmopolitan aquatic fungal species and a stream microbial community dominated by bacteria. In microcosms, we experimentally manipulated fungal diversity and bacterial absence/presence and assessed functional performances and fungal community composition after 14 d of incubation. Fungal community data were used to evaluate NDEs on leaf colonization. The individual fungal species were functionally distinct and fungal cultures were on average more efficient than the bacterial culture. In absence of bacteria, NDEs correlated with growth rate (negatively) and genetic divergence (positively), but were predominantly negative, suggesting that higher fungal diversity led to a lower colonization success (niche overlap). In both absence and presence of bacteria, the overall functional performances of the communities were largely defined by their composition (i.e., no interactions at the functional level). In the presence of bacteria, NDEs correlated with genetic divergence (positively) and were largely positive, suggesting higher fungal diversity stimulated colonization (niche complementarity). This stimulation may be driven by a bacteria‐induced inhibition of fungal growth, alleviating competition among fungi. Resulting feedback loops eventually promote fungal coexistence and synergistic interactions. Nonetheless, overall functional performances are reduced compared to bacteria‐free cultures. These findings highlight the necessity to conduct future studies, investigating biodiversity–ecosystem functioning relationships using artificial systems, without exclusion of key organisms naturally co‐occurring in the compartment of interest. Otherwise, study outcomes might not reflect true ecological relationships and ultimately misguide conservation strategies. [ABSTRACT FROM AUTHOR]

Mycocaliciales comprise non-lichenized either saprotrophic or lichenicolous fungi which occur in temperate and tropical regions. The mazaediate, saprotrophic and monospecific genus, Pyrgidium, is currently assigned to this order, yet the phylogenetic placement of the genus has remained uncertain due to the absence of molecular data. In order to investigate the systematic position of Pyrgidium, two specimens collected in Brazil and Thailand, respectively, were used to generate mtSSU, SSU, LSU and ITS sequences. However, given that most other representatives of this order only have LSU and ITS sequences available, the phylogenetic reconstruction was limited to these two markers. The phylogenetic analyses confirmed placement of the genus within Mycocaliciales, the genus possessing a sister group relationship with the lichenicolous genus Sphinctrina. Detailed morphological descriptions and illustrations are provided, including those for type specimens of the various synonyms subsumed under the hitherto only accepted species, Pyrgidium montellicum (Beltr.) Tibell. The ascospore morphology was investigated using compound and scanning electronic microscopy (SEM). Principal component analysis (PCA) was performed for the ascospore size using PC-ORD 7. The molecular data and re-examination of the type specimens support the monospecific nature of this genus.

Lignocellulose digestion in termites is achieved through the functional synergy between gut symbionts and host enzymes. However, some species have evolved additional associations with nest microorganisms that collaborate in the decomposition of plant biomass. In a previous study, we determined that plant material packed with feces inside the nests of Cornitermes cumulans (Syntermitinae) harbors a distinct microbial assemblage. These food nodules also showed a high hemicellulolytic activity, possibly acting as an external place for complementary lignocellulose digestion. In this study, we used a combination of ITS sequence analysis, metagenomics, and metatranscriptomics to investigate the presence and differential expression of genes coding for carbohydrate-active enzymes (CAZy) in the food nodules and the gut of workers and soldiers. Our results confirm that food nodules express a distinct set of CAZy genes suggesting that stored plant material is initially decomposed by enzymes that target the lignin and complex polysaccharides from fungi and bacteria before the passage through the gut, where it is further targeted by a complementary set of cellulases, xylanases, and esterases produced by the gut microbiota and the termite host. We also showed that the expression of CAZy transcripts associated to endoglucanases and xylanases was higher in the gut of termites than in the food nodules. An additional finding in this study was the presence of fungi in the termite gut that expressed CAZy genes. This study highlights the importance of externalization of digestion by nest microbes and provides new evidence of complementary digestion in the context of higher termite evolution.

Saprotrophic microbes are typically credited with producing extracellular enzymes that recycle organic matter, though roots and mycorrhizal fungi also can contribute and may compete with the saprotrophs. We examined extracellular enzyme activity associated with the mycorrhizospheres of arbuscular mycorrhizal, ectomycorrhizal, dual-colonized (arbuscular and ectomycorrhizal), and ericoid mycorrhizal plants in a fire chronosequence in Alaska. Bulk soil and soil from beneath host plants were gathered in July 2004 and assayed for five enzymes that target organic C, P, and N substrates. Compared to bulk soil, activities of the C-targeting enzymes β-1,4-glucosidase and peroxidase were lower in arbuscular mycorrhizospheres and ericoid mycorrhizospheres, respectively. Moreover, extracellular enzyme activity varied among mycorrhizosphere types. Specifically, N-targeting leucine aminopeptidase was highest in arbuscular mycorrhizospheres, followed by ericoid and ectomycorrhizal/dual-colonized mycorrhizospheres; β-1,4-glucosidase had the reverse pattern. In addition, enzymatic stoichiometry suggested that extracellular enzyme producers invested more in C-acquisition than in N-acquisition in recent fire scars compared to mature forests. These data extend previous findings that roots and mycorrhizal fungi compete with saprotrophs by showing that the strength of this effect varies by mycorrhizal host. As a result the community composition of mycorrhizal host plants might mediate enzymatic activity in boreal soils. © 2011 Elsevier GmbH.

Forest restoration has become one of the most important challenges for restoration ecology in the recent years. In this regard, soil fungi are fundamental drivers of forest ecosystem processes, with significant implications for plant growth and survival. However, the post-disturbance recovery of belowground communities has been rarely assessed, especially in highly degraded systems such as mines. Our aim was to compare forests and mined systems for biomass and structure of fungal communities in soil during early stages of tree establishment after disturbance. We performed ergosterol analysis and PacBio and Illumina sequencing of internal transcribed spacer 2 amplicons across soil layers in P. sylvestris, Q. robur and Q. ilex (holm oak) forests and naturally revegetated mined sites. In pine forests, total fungal biomass was significantly higher in litter and humus compared to mineral layers, with dominance of the mycorrhizal genera Tomentella, Inocybe and Tricholoma. Conversely, in oak forests the most abundant mycorrhizal genera were Tomentella, Cortinarius and Sebacina, but the biomass of saprotrophic fungi was greater in the litter layer compared to mycorrhizal fungi, with the genus Preussia being the most abundant. In the revegetated mined sites, ectomycorrhizal fungi dominated in the humus and mineral layers, with the mycorrhizal genus Oidiodendron being dominant. In contrast, in holm oak forests saprotrophic fungi dominated both soil humus and mineral layers, with the genera of Alternaria, Bovista and Mycena dominating the soil humus forest layer, while the genus Cadophora dominated the mineral layer. The habitat-specific differences in soil fungal community composition and putative functions suggest that an understanding of soil–plant–microbial interactions for different tree species and use of specific soil/litter inoculum upon planting/seeding might help to increase the effectiveness of tree restoration strategies in Mediterranean degraded sites.

Microscopic fungi synthesize a wide range of phenolic compounds that play an important role in cell wall formation, as well as perform signaling and protective functions. One of the important functions of phenolic compounds, primarily polyphenols, is antioxidant activity. The most active polyphenols are flavonoids, their synthesis in microscopic fungi has not been studied enough. The aim of the study was to determine the total phenols and flavonoids content and antioxidant activity of Talaromyces funiculosus strains isolated from different econiches. Methods. 20 strains of the microscopic fungus T. funiculosus - 10 endophytes and 10 saprotrophs were used in the experiments. Cultivation of filamentous fungi was performed under submerged conditions with shaking at 210-230 rpm in Erlenmeyer flasks containing 200 ml of Czapek liquid medium at a temperature 26±2° C for 6 days. The biomass of the strains was filtered, dried at 70° C and extracted with 95% methanol (1:50 w/v). The total phenols content was determined using Folin-Ciocalteu reagent by the method of Arora, Chandra (2010) with some modifications and expressed as mg of gallic acid equivalents (GAE) per g of dry weight mycelium. Flavonoids in each extract were determined spectrophotometrically with AlCl3 and expressed as mg of quercetin equivalents (QE) per g of dry weight mycelium. Antioxidant activity of methanolic extracts was measured as radical scavenging activity by the percentage inhibition of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Results. The total phenolic content of methanolic extracts of T. funiculosus strains ranged from 0.12±0.007 to 1.97±0.150 mg GAE/g. The highest level of phenolic compounds was found for saprotroph UCM F-16790 (1.97±0.150) and endophyte UCM F-16795 (1.71±0.137 mg GAE/g). The flavonoid content in methanolic extracts of the studied strains varied in the range of 0.02±0.001 - 0.39±0.041 mg QE/g. All studied strains of T. funiculosus showed antioxidant activity against DPPH radical, which was 12.19±2.34 - 60.37±7.24% inhibition. Statistical analysis revealed a strong positive correlation between the total phenols and flavonoids content (Pearson's correlation coefficient r=0.92); between antioxidant activity, phenols (r=0.82) and flavonoids (r=0.81) content in methanol extracts of T. funiculosus strains. The total content of phenols and flavonoids and antioxidant activity did not depend on the trophic group of the studied strains. The moderate correlation between flavonoids content and antioxidant activity of methanolic extracts of endophytic T. funiculosus strains (r=0.46) may be related to their ability to synthesize a wider range of polyphenolic compounds with antioxidant activity. Conclusions. The studied T. funiculosus strains have the ability to synthesize phenolic compounds and flavonoids in different concentrations. Correlation analysis revealed strong correlations between total phenolic and flavonoid contents and antioxidant activity. The reason for phenomenon of moderate correlation (r=0.46) between flavonoid content and antioxidant activity in endophytic strains may be the synthesis of other compounds by individual strains. The determination of individual components synthesized by the most active strains is of scientific interest for further study. T. funiculosus UСM F-16795 and UСM F-16790 strains had a quite high level of phenols and flavonoids. Obtained data may be promising for the search for phenolic compounds with antioxidant properties to increase plant resistance to negative impacts of environmental stress factors. [ABSTRACT FROM AUTHOR]

Summary: Soil fungi represent a major component of below‐ground biodiversity that determines the succession and recovery of forests after disturbance. However, their successional trajectories and driving mechanisms following wildfire remain unclear.We examined fungal biomass, richness, composition and enzymes across three soil horizons (Oe, A1 and A2) along a near‐complete fire chronosequence (1, 2, 8, 14, 30, 49 and c. 260 yr) in cold‐temperate forests of the Great Khingan Mountains, China. The importance of soil properties, spatial distance and tree composition were also tested.Ectomycorrhizal fungal richness and β‐glucosidase activity were strongly reduced by burning and significantly increased with 'time since fire' in the Oe horizon but not in the mineral horizons. Time since fire and soil C : N ratio were the primary drivers of fungal composition in the Oe and A1/A2 horizons, respectively. Ectomycorrhizal fungal composition was remarkably sensitive to fire history in the Oe horizon, while saprotroph community was strongly affected by time since fire in the deeper soil horizon and this effect emerged 18 years after fire in the A2 horizon.Our study demonstrates pronounced horizon‐dependent successional trajectories following wildfire and indicates interactive effects of time since fire, soil stoichiometry and spatial distance in the reassembly of below‐ground fungal communities in a cold and fire‐prone region. [ABSTRACT FROM AUTHOR]

The paper revises data on the identification of peptidases groups involved in the growth of fungi and inhibitors of these peptidases. The available data on the diversity, significance, representation, and characteristics of proteolytic enzymes in representatives of the Aspergillus, Penicillium, Trichoderma, and Alternaria genera are considered. It was concluded that serine, metal, and glutamine peptidases are necessary for the growth of fungi. Therefore, these enzymes are considered as promising targets for peptidase inhibitors, which can serve as a rationale for the search for such inhibitors and the development of new biocidal agents on their basis for protecting art objects from biodestructors. [ABSTRACT FROM AUTHOR]

Fungi play many essential roles in ecosystems. They facilitate plant access to nutrients and water, serve as decay agents that cycle carbon and nutrients through the soil, water and atmosphere, and are major regulators of macro‐organismal populations. Although technological advances are improving the detection and identification of fungi, there still exist key gaps in our ecological knowledge of this kingdom, especially related to function. Trait‐based approaches have been instrumental in strengthening our understanding of plant functional ecology and, as such, provide excellent models for deepening our understanding of fungal functional ecology in ways that complement insights gained from traditional and ‐omics‐based techniques. In this review, we synthesize current knowledge of fungal functional ecology, taxonomy and systematics and introduce a novel database of fungal functional traits (FunFun). FunFun is built to interface with other databases to explore and predict how fungal functional diversity varies by taxonomy, guild, and other evolutionary or ecological grouping variables. To highlight how a quantitative trait‐based approach can provide new insights, we describe multiple targeted examples and end by suggesting next steps in the rapidly growing field of fungal functional ecology. [ABSTRACT FROM AUTHOR]

Data on the abundance of heterotrophic bacterioplankton and bacteriobenthos in the northern and middle parts of the Caspian during the period from 2013 to 2017 are presented. In the waters of the northern part of the Caspian, a peak in the number of saprotrophs and crude oil degraders was recorded in 2013. In the middle part of the Caspian and in the region of the Mangyshlak regression, high numbers of heterotrophic bacteria were recorded in 2013 and 2016. The biodiversity of bacterioplankton in the surveyed areas is almost the same; the species composition of saprotrophs and crude oil degraders is identical. In the bottom sediments of the northern and middle parts of the Caspian Sea, two peaks of saprotrophic bacteriobenthos development (in 2013 and 2016) were recorded; in the region of the Mangyshlak threshold, the concentration of saprotrophs remained stable. The number of crude oil degraders was inferior to those of saprotrophs, while the proportion of crude oil degraders to saprotrophs changed annually. The species composition of saprotrophs is relatively stable, the biodiversity of oil-oxidizing bacteriobenthos has changed in the direction of increasing the proportion of non-fermenting bacteria. Constant changes in the ratio of the number of saprotrophs and crude oil degraders, together with the transformations of the dominant groups of the species composition of bacteria, indicated the instability of bacteriobenthos, and, as a result, the vulnerability of the microecosystem of bottom sediments under changing environmental conditions. [ABSTRACT FROM AUTHOR]

Wildfire is the dominant disturbance in boreal forests and fire activity is increasing in these regions. Soil fungal communities are important for plant growth and nutrient cycling postfire but there is little understanding of how fires impact fungal communities across landscapes, fire severity gradients, and stand types in boreal forests. Understanding relationships between fungal community composition, particularly mycorrhizas, and understory plant composition is therefore important in predicting how future fire regimes may affect vegetation. We used an extreme wildfire event in boreal forests of Canada's Northwest Territories to test drivers of fungal communities and assess relationships with plant communities. We sampled soils from 39 plots 1 year after fire and 8 unburned plots. High‐throughput sequencing (MiSeq, ITS) revealed 2,034 fungal operational taxonomic units. We found soil pH and fire severity (proportion soil organic layer combusted), and interactions between these drivers were important for fungal community structure (composition, richness, diversity, functional groups). Where fire severity was low, samples with low pH had higher total fungal, mycorrhizal, and saprotroph richness compared to where severity was high. Increased fire severity caused declines in richness of total fungi, mycorrhizas, and saprotrophs, and declines in diversity of total fungi and mycorrhizas. The importance of stand age (a surrogate for fire return interval) for fungal composition suggests we could detect long‐term successional patterns even after fire. Mycorrhizal and plant community composition, richness, and diversity were weakly but significantly correlated. These weak relationships and the distribution of fungi across plots suggest that the underlying driver of fungal community structure is pH, which is modified by fire severity. This study shows the importance of edaphic factors in determining fungal community structure at large scales, but suggests these patterns are mediated by interactions between fire and forest stand composition. [ABSTRACT FROM AUTHOR]

Fungi play prominent roles in ecosystem services (e.g., nutrient cycling, decomposition) and thus have increasingly garnered attention in restoration ecology. However, it is unclear how most management decisions impact fungal communities, making it difficult to protect fungal diversity and utilize fungi to improve restoration success. To understand the effects of restoration decisions and environmental variation on fungal communities, we sequenced soil fungal microbiomes from 96 sites across eight experimental Everglades tree islands approximately 15 years after restoration occurred. We found that early restoration decisions can have enduring consequences for fungal communities. Factors experimentally manipulated in 2003–2007 (e.g., type of island core) had significant legacy effects on fungal community composition. Our results also emphasized the role of water regime in fungal diversity, composition, and function. As the relative water level decreased, so did fungal diversity, with an approximately 25% decline in the driest sites. Further, as the water level decreased, the abundance of the plant pathogen–saprotroph guild increased, suggesting that low water may increase plant-pathogen interactions. Our results indicate that early restoration decisions can have long-term consequences for fungal community composition and function and suggest that a drier future in the Everglades could reduce fungal diversity on imperiled tree islands.