Fungal Species Composition Research Articles

Effects of saline-alkali stress on bacterial and fungal community diversity in Leymus chinensis rhizosphere soil.

The salinization of grassland in arid and semi-arid areas is a serious environmental issue in China. Halophytes show extreme salt tolerance and are grown in saline-alkaline environments. Their rhizosphere microorganisms contribute significantly to plant stress tolerance. To study bacterial and fungal community structure changes in Chinese ryegrass (Leymus chinensis) rhizosphere soil under salt and alkali stress, pot experiments were conducted with different salt and alkali stress intensities. High-throughput sequencing was conducted, and the microbial diversity, community structure, and driving factors were analyzed in rhizosphere soil. The salinization of grassland in arid and semi-arid areas is a serious environmental issue in China. Halophytes show extreme salt tolerance and grow in saline-alkaline environments. A total of 549 species of bacteria from 28 phyla and 250 species from 11 phyla of fungi were detected in the rhizosphere soil of Leymus chinensis with different saline-alkali gradients. Alpha diversity analysis along saline-alkali gradients showed that bacterial community richness and diversity were the highest in the moderate saline-alkali group (pH = 8.28, EC = 160.4 μS·cm-1), while fungi had high richness and diversity in the control group (pH = 7.35, EC = 134.5 μS·cm-1). The bacteriophyta Proteobacteria, Acidobacteria, Plantomycetes, and the eumycota Ascomycota, Basidiomycota, and Glomeromycota were found with relative abundances of more than 10%. Saline-alkali gradients had significant effects on the abundance of the bacterial and fungal groups in the rhizosphere. The distribution of bacterial colony structure was not significant at the species level (P > 0.05). However, there were significant differences in the distribution of fungal structure and considerable differences in the composition of fungal species among the moderate saline-alkali group, severe saline-alkali group, and control group (P < 0.05). Correlation analysis showed that the bacterial phylum Gemmatimonadetes had a highly significant positive correlation with pH and EC (P < 0. 01). Saline-alkali stress significantly inhibited the abundance of the bacteria Latescibacteria, Cyanobacteria, and Bacteroides, and the fungi Zoopagomycota, Mortierllomycota, and Cryptomycota (P < 0. 05). Compared with fungi, bacterial community composition was most closely correlated with soil salinization. This report provided new insights into the responses of relationships between rhizosphere soil microorganisms and salt and alkali tolerance of plants.

Fungal communities in feces of the frugivorous bat Ectophylla alba and its highly specialized Ficus colubrinae diet

BackgroundBats are important long-distance dispersers of many tropical plants, yet, by consuming fruits, they may disperse not only the plant’s seeds, but also the mycobiota within those fruits. We characterized the culture-dependent and independent fungal communities in fruits of Ficus colubrinae and feces of Ectophylla alba to determine if passage through the digestive tract of bats affected the total mycobiota.ResultsUsing presence/absence and normalized abundance data from fruits and feces, we demonstrate that the fungal communities were significantly different, even though there was an overlap of ca. 38% of Amplicon Sequence Variants (ASVs). We show that some of the fungi from fruits were also present and grew from fecal samples. Fecal fungal communities were dominated by Agaricomycetes, followed by Dothideomycetes, Sordariomycetes, Eurotiomycetes, and Malasseziomycetes, while fruit samples were dominated by Dothideomycetes, followed by Sordariomycetes, Agaricomycetes, Eurotiomycetes, and Laboulbeniomycetes. Linear discriminant analyses (LDA) show that, for bat feces, the indicator taxa include Basidiomycota (i.e., Agaricomycetes: Polyporales and Agaricales), and the ascomycetous class Eurotiomycetes (i.e., Eurotiales, Aspergillaceae). For fruits, indicator taxa are in the Ascomycota (i.e., Dothideomycetes: Botryosphaeriales; Laboulbeniomycetes: Pyxidiophorales; and Sordariomycetes: Glomerellales). In our study, the differences in fungal species composition between the two communities (fruits vs. feces) reflected on the changes in the functional diversity. For example, the core community in bat feces is constituted by saprobes and animal commensals, while that of fruits is composed mostly of phytopathogens and arthropod-associated fungi.ConclusionsOur study provides the groundwork to continue disentangling the direct and indirect symbiotic relationships in an ecological network that has not received enough attention: fungi-plants-bats. Findings also suggest that the role of frugivores in plant-animal mutualistic networks may extend beyond seed dispersal: they may also promote the dispersal of potentially beneficial microbial symbionts while, for example, hindering those that can cause plant disease.

Effects of biodegradable films on melon quality and substrate environment in solar greenhouse

With the increase in plastic pollution of farmland substrate, biodegradable mulch film research has become a hotspot. However, the degradation rate of biodegradable plastic film over the entire crop growth period is still unclear, as well as its impact on crop growth and product quality. Here, several properties of two kinds of composite biodegradable mulch films, PBAT/PLA-[S1] and PBAT/lignin-[S2], are studied with polyethylene-[PE] and uncovered substrate (CK) as controls. We tested the differences in morphological characterization, physical properties, and weight loss rate of the plastic films, as well as the effects of the different plastic films on melon yield and quality, substrate temperature and humidity, physical and chemical properties of the substrate, and substrate fungal species composition. Compared to PE, biodegradable plastic films S1 and S2 increased substrate temperature and the net photosynthetic rate of leaves. The results of substrate 18 s rDNA assay of CK, PE, S1, and S2 after 80 days of treatment and pre-treatment showed that a total of 12 fungal phylum, with 317 fungal genera were found, in which Ascomycota as the main phyla and Penicillium as the main genera. Compared with PE, the S2 treatment significantly increased the single fruit weight, central sugar content and soluble sugar of melon by 225.35 g, 1.26%, and 0.68%, respectively (p < 0.05). When buried for 240 d, the weight loss rate of S2 was significantly increased by 86.08% compared with PE (p < 0.05). From these results, we extrapolated that covering the substrate with the most biodegradable film, PBAT/lignin composite (10 μm), improved the yield and fruit quality of the melon in winter greenhouse production.

Microbiological indoor air quality of hospital buildings with different ventilation systems, cleaning frequencies and occupancy levels

Pathogenic airborne microbes are the potential source of infectious diseases transmission. This study aimed to investigate and compare the microbial load, composition and prevalence of fungal and bacterial species at hospital sites facilitated with different ventilation systems and having different disinfection frequencies and occupancy levels. For this purpose, sixteen sampling sites were selected in two public hospital buildings including outpatient departments (OPDs), surgical wards, operation theaters (OTs), emergency departments, waiting room, burn unit, intensive care unit, nursing unit and medical laboratory. Results showed highest bacterial (829–4980 CFU/m3) and fungal levels (90–920 CFU/m3) in OPDs and wards respectively, whereas lowest concentration was observed in OTs of both hospitals. Overall, sites facilitated with central/mechanical heating ventilation and air conditioning (HVAC) system, higher cleaning frequency and lower occupant's density showed lower contamination levels. Staphylococcus spp. (53%), Micrococcus spp. (30%) and Bacillus spp. (11%) were found as abundantly occurring bacterial microbiota whereas Aspergillus spp. (67%) and Penicillium spp. (28%) were predominant fungal genera observed.

АНАЛИЗ КОНТАМИНИРОВАННОСТИ ОДЕЖДЫ И ОБОРУДОВАНИЯ МИКРОСКОПИЧЕСКИМИ ГРИБАМИ ПОСЛЕ ПОСЕЩЕНИЯ ПЕЩЕР КИНДЕРЛИНСКАЯ И ШУЛЬГАН-ТАШ

Caves are extreme ecosystems whose microbiomes are very sensitive to invasion by extraneous microbial species. The entry of such organisms from one cave into another can occur due to anthropogenic transfer, which makes it possible to bypass natural barriers. The article presents materials on the analysis of microscopic fungi contamination of clothing and equipment after working in caves. It is shown that after visiting the cave Kinderlinskaya and Shulgan-Tash, a significant number of micromycete species settle on clothes and equipment. Twenty-one species of microscopic fungi were found, as well as yeast, light and dark-colored sterile forms. The isolated species correspond to the typical species composition of fungi in a particular cave. Gloves turned out to be the most contaminated. Washing made it possible to significantly reduce the number and species richness of micromycetes on clothes. Thus, following simple rules can significantly reduce the risk of anthropogenic transfer of microorganisms between caves.

The occurrence of Fusarium species in white spears of Asparagus officinalis

The aim of the study was to determine the species composition of fungi of the Fusarium genus found on white Asparagus officinalis spears, depending on the presence or absence of disease symptoms, age of the plantation, date of harvest and the place from which samples were collected for mycological analysis. Additionally, the pathogenicity of selected Fusarium spp. isolates was determined. A. officinalis L. was cultivated for white spears. The research was conducted on the German dioecious cultivar ‘Eposs’. Samples of A. officinalis spears for tests were collected from two plantations. Six species of fungi of the Fusarium genus were identified in the asparagus spears: F. culmorum, F. equiseti, F. oxysporum, F. proliferatum, F. solani, and F. fujikuroi. Among the Fusarium species colonizing Asparagus officinalis the greatest threat is F. oxysporum. Always there are more isolates in the spears with the symptoms, in epidermis. The late harvest date favors the development of fusariosis. This means that the spears harvested at the latest date (late June) are the most heavily colonised by fungi. The isolates of fungi of the Fusarium genus collected from the spears exhibit pathogenicity against A. officinalis plants.

Species composition of Fusarium spp. on winter wheat in the Right Bank Polissya of Ukraine

Goal. To clarify the species composition of fungi of the genus Fusarium on winter wheat and to establish their share in this complex.&#x0D; Methods. Field and laboratory. Phytopathological analysis of winter wheat grain collected from industrial crops in the area of the Right-Bank Polissya of Ukraine (Zhytomyr region). During the examination of crops for fusariosis of the ear, samples (50 pieces of the affected ear) were taken with typical features. Accounting and selection were performed at the end of the phase of milk-wax ripeness. The collected material was herbariumed and labeled (indicating the variety, place of harvest, phase of plant development). In the laboratory, morphological and cultural features, forms of conidia and the presence of chlamydospores were taken into account during identification. The studies were performed on the environment of Chapek and KGA. In the absence of typical sporulation, the microculture method was used. The test material was photographed using a Nikon FX- 35 DX photoresist on a Nikon microscope.&#x0D; Results. In 2019—2020, 5 species and varieties of fungi of the genus Fusarium, which belong to 4 sections of the genus Fusarium, were identified on the grain of winter wheat. Two species were found from the Diskolor section — F. graminearum and F. culmorum. Section Roseum was represented by one species of F. avenaceum, section Sporotrichiella — species F. poae; section Elegans — species F. fujikuroi (according to the classification of V.Y. Bilay). On the infected grain, the dominant position was occupied by the species F. culmorum (42%). The share of colonized grain by F. avenaceum and F. poae was 24% and 21%, respectively. A small proportion were colonized by F. fujikuroi (8%) and F. graminearum (5%).&#x0D; Conclusion. Laboratory studies have shown that in the Right Bank Polissya of Ukraine the main causative agents of winter wheat fusariosis were species: F. sulmorum, F. avenaceum, F. poae, F. fujikuroi, F. graminearum. Among them, the dominant position was occupied by the species F. culmorum, the average frequency of isolation of which was 42%.

The influence of aboveground and belowground species composition on spatial turnover in nutrient pools in alpine grasslands

AbstractAimAn important research question in ecology is how climate and the biodiversity of aboveground plants and belowground microbiomes affect ecosystem functions such as nutrient pools. However, little is studied on the concurrent role of above‐ and belowground species composition in shaping the spatial distribution patterns of ecosystem functions across environmental gradients. Here, we investigated the relationships between the taxonomic composition of plants, soil bacteria and soil fungi and spatial turnover in nutrient pools, and assessed how species composition–nutrient pool relationships were mediated by contemporary climatic conditions.LocationQinghai‐Tibetan Plateau.Time periodCurrent.Major taxa studiedPlants, soil bacteria and soil fungi.MethodsWe surveyed plant assemblages, sampled the taxonomic composition of soil bacteria and soil fungi, and measured plant‐ and soil‐mediated nutrient pools at 60 alpine grasslands on the Qinghai‐Tibetan Plateau. Using Mantel tests, structural equation models and general linear models, we investigated the relative importance of the taxonomic composition of plant, soil bacterial, and soil fungal communities on the spatial turnover of alpine grassland nutrient pools.ResultsWe found that the taxonomic composition of plant, soil bacterial, and soil fungal communities was associated with local climate. However, the effects of local climate on the spatial turnover of plant‐ and soil‐mediated nutrient pools were mainly indirect and mediated through plant and soil bacterial species composition, but not through soil fungal species composition. We further found that the replacement component of soil bacterial β‐diversity and the richness difference of plant β‐diversity were the direct predictors of nutrient pools in the alpine grasslands.Main conclusionsThese results highlight that belowground bacterial composition together with aboveground plant species composition are related to spatial turnover in nutrient pools, perhaps even driving it. Conserving above‐ and belowground biodiversity may therefore safeguard against the impacts of local climate on the functions of climate‐sensitive alpine grasslands.

Determination of the species of fungi of the genus Fusarium by molecular method

Currently, more than 10,000 species of fungi associated with plants have been found, and it is not surprising that fungal diseases cause a lot of harm. Most species of the genus Fusarium are soil protrophs that live on dead plant remains, in the rhizosphere of plants, on the surface of roots. They cause rot of roots, seeds, fruits, tubers, root crops. All forms of fusariums progress at high temperatures and humidity. The analysis of literary sources and experimental data allowed us to formulate the purpose of our research: “To analyze the species diversity of fungi of the genus Fusarium from the soil, table carrot plants, depending on the ecological and geographical zones of growth.” As a result, using PCR analysis, 13 samples attributed to F. langsethiae were identified; 2 samples of F. ochusrohim; 8 samples of F. roae; 2 of F. sporotrichioides; 1 sample attributed to F. sulmorum, this sample was collected in the Rostov region and the Moscow region. It was also revealed that the diversity of soil and climatic conditions in different zones leads to a change in the species composition of representatives of R. Fusarium: the species composition of fungi of R. Fusarium varies significantly depending on agro-climatic conditions. In wetter and warmer conditions (southern regions), specific species of F. culmorum, F. sporotrichiella, and F. oxysporum dominate. F. heterosporum, F. nivale are less common; F. graminearum species lives on plant residues, on plant roots or in the rhizosphere zone, but practically does not occur in the soil in its pure form. Thus, this direction is promising for the study of fungi of the genus Fusarium, since this microorganism lives in the soil and on plants. It is advisable to identify the pathogen from samples from different regions to significantly increas the representativeness of samples within the regions with further identification of diverse mycelium, thereby creating a scale of diverse mycelium.

Fusarium head blight in the Russian Far East: 140 years after description of the 'drunken bread' problem.

The first appearance of Fusarium head blight (FHB)—and the beginning of scientific research of this disease—occurred the Far East region of Russia at the end of the 19th century. In the summer of 2019, in the Amur region, which comprises 60–70% of grain production in the Russian Far East, flooding caused a state of emergency. The quality of wheat and barley grains grown under natural conditions of FHB outbreaks, including grain infection, fungal species composition, DNA content of F. graminearum and chemotypes, and the presence of various mycotoxins, was studied. Fusarium infection rates reached extremely high percentages, 51–98%, the majority of which were F. graminearum infections. The amount of F. graminearum DNA in wheat grain samples was higher than in the barley grain samples and averaged 6.1 and 2.1 pg/ng, respectively. The content of deoxynivalenol (DON) in the wheat samples reached 13,343 ppb and in barley reached 7,755 ppb. A multilocus genotyping assay was conducted on the partially sequenced fragments of the translation elongation factor EF-1a, ammonium ligase gene, reductase gene, and 3-O-acetyltransferase gene in 29 Fusarium graminearum sensu lato strains from the grain harvested in the Amur region. All strains from the Far East region were characterized as F. graminearum sensu stricto; 70% were the 15-AcDON chemotype, while the other strains were the 3-AcDON chemotype. According to the results, after 140 years of study of FHB, we are still not very successful in controlling this disease if conditions are favorable for pathogen development. Even at present, some of the grain harvested must be destroyed, as high contamination of mycotoxins renders it unusable.

Microbial growth and volatile organic compound (VOC) emissions from carpet and drywall under elevated relative humidity conditions

BackgroundMicrobes can grow in indoor environments if moisture is available, and we need an improved understanding of how this growth contributes to emissions of microbial volatile organic compounds (mVOCs). The goal of this study was to measure how moisture levels, building material type, collection site, and microbial species composition impact microbial growth and emissions of mVOCs. We subjected two common building materials, drywall, and carpet, to treatments with varying moisture availability and measured microbial communities and mVOC emissions.ResultsFungal growth occurred in samples at >75% equilibrium relative humidity (ERH) for carpet with dust and >85% ERH for inoculated painted drywall. In addition to incubated relative humidity level, dust sample collection site (adonis p=0.001) and material type (drywall, carpet, adonis p=0.001) drove fungal and bacterial species composition. Increased relative humidity was associated with decreased microbial species diversity in samples of carpet with dust (adonis p= 0.005). Abundant volatile organic compounds (VOCs) that accounted for >1% emissions were likely released from building materials and the dust itself. However, certain mVOCs were associated with microbial growth from carpet with dust such as C10H16H+ (monoterpenes) and C2H6SH+ (dimethyl sulfide and ethanethiol). CO2 production from samples of carpet with dust at 95% ERH averaged 5.92 mg hr-1 kg-1, while the average for carpet without dust at 95% ERH was 2.55 mg hr-1 kg-1.ConclusionMicrobial growth and mVOC emissions occur at lower relative humidity in carpet and floor dust compared to drywall, which has important implications for human exposure. Even under elevated relative humidity conditions, the VOC emissions profile is dominated by non-microbial VOCs, although potential mVOCs may dominate odor production.5qHJBwjppp9jyb9CEJTu9oVideo

Fungal Interactions Matter: Tricholoma matsutake Domination Affect Fungal Diversity and Function in Mountain Forest Soils.

Simple SummaryTricholoma matsutake forms a symbiotic association with hosts, developing mycelial aggregations, called ‘shiro’. The fungal diversity living in shiro soil play key roles in nutrient cycles for this economically important mushroom, but have not been profiled across large spatial and environmental gradients. Here, we mainly aimed to study the fungal characteristics in the bulk soil (non-shiro) and shiro, using phospholipid fatty acids and illuninan sequencing in five habitats across landscapes in southwestern China. T. matsutake causes a lower fungal diversity and simplifies the fungal community composition in shiro soil compared with non-shiro soil across five forest types. We also found that geo-graphical proximity was accompanied by a similar fungal community structure but different contributions from specific species under five forest types. Among the co-existed fungi, Oidiodendron were found to collaborate with T. matsutake, whereas Helotiales and Mortierella showed a negative correlation with it. The selection of these taxa may be related to their ability to compete with resources and different nutrient strategists in the soil. Overall, we conclude that T. matsutake generate a dominance effect to shape the fungal community and diversity in shiro soil across distinctive forest types.Tricholoma matsutake forms a symbiotic association with coniferous trees, developing mycelial aggregations, called ‘shiro’, which are characterized by distinct chemical and physical properties from nearby forest bulk soil. The fungal diversity living in shiro soil play key roles in nutrient cycles for this economically important mushroom, but have not been profiled across large spatial and environmental gradients. Samples of shiro and non-shiro (nearby bulk soil) were taken from five field sites where sporocarps naturally formed. Phospholipid fatty acids (PLFA) and Illumina MiSeq sequencing were combined to identify fungal biomass and community structure. Matsutake dominated in the shiro, which had a significantly reduced saprotrophic fungi biomass compared to non-shiro soil. Fungal diversity was negatively correlated with the relative abundance of T. matsutake in the shiro soil. The fungal community in the shiro was characterized by similar fungal species composition in most samples regardless of forest types. Matsutake coexisted with a specific fungal community due to competition or nutrient interactions. Oidiodendron was positively correlated with the abundance of T. matsutake, commonly cohabitant in the shiro. In contrast, Helotiales and Mortierella were negatively correlated with T. matsutake, both of which commonly inhabit the non-shiro soil but do not occur in shiro soils. We conclude that T. matsutake generate a dominance effect to shape the fungal community and diversity in shiro soil across distinctive forest types.

Seasonal Dynamics of Fungi Associated with Healthy and Diseased Pinus sylvestris Needles in Northern Europe.

The relationship between the ecological success of needle pathogens of forest trees and species richness of co-inhabiting endophytic fungi is poorly understood. One of the most dangerous foliar pathogens of pine is Dothistroma septosporum, which is a widely spread threat to northern European forests. We sampled two Pinus sylvestris sites in Estonia and two in Norway in order to analyse the relations between the abundance of D. septosporum and overall fungal richness, specific fungal species composition, time of season, needle age and position in the canopy. In both countries, the overall species richness of fungi was highest in autumn, showing a trend of increase with needle age. The overall species richness in the second-year needles in Estonia and third-year needles in Norway was similar, suggesting that a critical colonization threshold for needle shed in P. sylvestris is breached earlier in Estonia than in Norway. The fungal species richness in P. sylvestris needles was largely affected by Lophodermium conigenum. Especially in older needles, the relative abundance of L. conigenum was significantly higher in spring compared to summer or autumn. The timing of recruitment and colonization mechanisms of different foliage endophytes are shortly discussed.

Site-Dependent Relationships Between Fungal Community Composition, Plant Genotypic Diversity and Environmental Drivers in a Salix Biomass System.

Soil fungi are strongly affected by plant species or genotypes since plants modify their surrounding environment, but the effects of plant genotype diversity on fungal diversity and function have not been extensively studied. The interactive responses of fungal community composition to plant genotypic diversity and environmental drivers were investigated in Salix biomass systems, posing questions about: (1) How fungal diversity varies as a function of plant genotype diversity; (2) If plant genotype identity is a strong driver of fungal community composition also in plant mixtures; (3) How the fungal communities change through time (seasonally and interannually)?; and (4) Will the proportion of ECM fungi increase over the rotation? Soil samples were collected over 4 years, starting preplanting from two Salix field trials, including four genotypes with contrasting phenology and functional traits, and genotypes were grown in all possible combinations (four genotypes in Uppsala, Sweden, two in Rostock, Germany). Fungal communities were identified, using Pacific Biosciences sequencing of fungal ITS2 amplicons. We found some site-dependent relationships between fungal community composition and genotype or diversity level, and site accounted for the largest part of the variation in fungal community composition. Rostock had a more homogenous community structure, with significant effects of genotype, diversity level, and the presence of one genotype ("Loden") on fungal community composition. Soil properties and plant and litter traits contributed to explaining the variation in fungal species composition. The within-season variation in composition was of a similar magnitude to the year-to-year variation. The proportion of ECM fungi increased over time irrespective of plant genotype diversity, and, in Uppsala, the 4-mixture showed a weaker response than other combinations. Species richness was generally higher in Uppsala compared with that in Rostock and increased over time, but did not increase with plant genotype diversity. This significant site-specificity underlines the need for consideration of diverse sites to draw general conclusions of temporal variations and functioning of fungal communities. A significant increase in ECM colonization of soil under the pioneer tree Salix on agricultural soils was evident and points to changed litter decomposition and soil carbon dynamics during Salix growth.

Different patterns in root and soil fungal diversity drive plant productivity of the desert truffle Terfezia claveryi in plantation.

The desert truffle Terfezia claveryi is one of the few mycorrhizal fungi currently in cultivation in semiarid and arid areas. Agroclimatic parameters seem to affect its annual yield, but there is no information on the influence of biotic factors. In this study, fungal diversity was analysed by high-throughput sequencing of the ITS2 rDNA region from soil and root samples to compare productive and non-productive mycorrhizal plants in a 4-years old plantation (Murcia, Spain). The fungal metaprofile was dominated by Ascomycota phylum. Desert truffle productivity was driven by different patterns of fungal species composition in soil (species replacement) and root (species richness differences). Moreover, positive associations for ectomycorrhizal and negative for arbuscular mycorrhizal guilds were found in productive roots, and positive associations for fungal parasite-plant pathogen guild in non-productive ones. Soil samples were dominated by pathotroph and saprotroph trophic modes, showing positive associations for Aureobasidium pullulans and Alternaria sp. in productive areas, and positive associations for Fusarium sp. and Mortierella sp. were found in non-productive soils. Finally, some significant OTUs were identified and associated to ascocarp producing patches, which could serve as predictive and location markers of desert truffle production.

Fungi associated with disease symptoms on Pinus mugo needles in the Polish Tatra Mountains

Dwarf mountain pine, Pinus mugo, is an important component of the subalpine and alpine zone in Europe. For several years, in one of the natural areas of the occurrence of this species in the Polish Tatras, an intensified decline of the assimilation apparatus has been observed. The studies conducted in 2016–2020 were aimed at determining the types of disease symptoms occurring on P. mugo needles and at identifying the species composition of fungi within symptomless and diseased needles. We isolated 57 taxa from 6 types of disease symptoms and from needles without disease symptoms, identified on the basis of morphological features and molecular analyses. Absolute parasites were represented by only one species of Coleosporium senecionis, which was identified by the aecium stage. The genus Lophodermium was represented by three species: L. conigenum, L. corconticum and L. pini-mugonis. So far, L. corconticum was known only from the Karkonosze Mountains in Poland, and L. pini-mugonis from the German Alps. In addition, the more frequently isolated species included: Sydowia polyspora, Hendersonia sp., Nemania serpens, Leptomelanconium allescheri, Cladosporium spp., Biscogniauxia nummularia and Alternaria spp. Some taxa were associated with only one type of disease symptom, while some species of fungi were found to be associated with different symptoms. Twelve species of fungi were isolated from living symptomless needles, some of which were subsequently found in association with nectrotic areas on needles, e.g., Lophodermium corconticum, L. conigenum and Leptomelanconium allescheri. L. pinastri has not been found in the present studies. In the discussion, an attempt was made to assess the role of some of the identified species of fungi in causing the disease process of P. mugo needles.

Вплив умов місцезростання на зміну видового складу мікобіоти насіння сосни звичайної

The species composition of micromycetes of Scots pine seeds, collected from plantations growing in different forest vegetation conditions and selected from trees of different age groups, was studied. It was found that the most common species of micromycetes - Alternaria alternata, Cladosporium cladosporioides, Fusarium oxysporum, Mycelia sterilia. Dominant species of micromycetes, in particular Penicillium cyclopium, Alternaria alternata, Cladosporium cladosporioides, Fusarium sambucinum, which are the most dangerous for the development of healthy planting material, have been identified. The largest number of micromycetes from seeds of plantations growing wet birch (A3) - 189 and fresh beer (A2) - 103 micromycetes, and the smallest - fresh (B2) and raw subir (B3), respectively: 92 and 93 isolates. The highest frequency of occurrence on experimental samples of seeds of Scots pine, selected from fresh pine stands, had micromycetes: Penicillium cyclopium, Alternaria alternata, Trithothecium roseum micromycetes had the highest frequency of occurrence of Scots pine seeds taken from fresh pine stands, and Mortierella alpine, P. canescens, P. lanosum, P. variabile, Fusarium sporotrich had the lowest frequency. It was noted that Mycelia sterilia (9.2%), Fusarium sporotrichioides (9.6%) were the most common on seeds selected from trees of different age groups, while Alternaria alternata, A. tenuissima, Fusarium verticillioides were the least common. Trichothecium roseum - 1.9%. The similarity of the species composition of mycobiota seeds selected from young and medieval plantations (similarity index - 84.2%) and medieval and mature (similarity index - 89.4%) was studied. Less similarity was observed between the species composition of fungi identified on seeds selected from young and mature plantations (similarity index is -73.6%). The most similar were the seeds of medieval and mature plantations, the least similar - the young and mature. The seeds were selected from different age groups, are different in species composition of micromycetes (similarity varied between 73.6 - 89.4%). Keywords: age groups of trees, mycobiota, type of forest vegetation conditions, micromycetes, Scots pine.

Greater Mouse-Eared Bats (Myotis myotis) Hibernating in the Nietoperek Bat Reserve (Poland) as a Vector of Airborne Culturable Fungi.

Simple SummaryFungi and bats are important parts of many ecosystems where they play critical ecological roles. Bats can contribute to an increase of airborne fungi in underground ecosystems, which may cause allergies and infections in mammals. Our study contributes to gaining new knowledge about aeromycota present in the close vicinity of the hibernating greater mouse-eared bat (Myotis myotis) in an underground site. M. myotis is the most common bat species in Europe with direct human contact. Hibernating M. myotis contribute to an increase in the concentration of aeromycota in the underground site and is a vector/reservoir of microscopic fungi, including those that are potential threats to mammal populations; however, the concentration of aeromycota at this site does not pose a threat to human health.Bats can contribute to an increase of aeromycota in underground ecosystems and might be a vector/reservoir of microorganisms; however, there is no information about the number and species composition of fungi around hibernating bats. One of the most common species in Europe with direct human contact is the greater mouse-eared bat (Myotis myotis). The goal of our research was the first report of the airborne fungi present in the close vicinity of hibernating M. myotis in the Nietoperek bat reserve (Western Poland) by the use of culture-based techniques and genetic and phenotypic identifications. Aerobiological investigations of mycobiota under hibernating bats were performed on two culture media (PDA and YPG) and at two incubation temperatures (7 and 24 ± 0.5 °C). Overall, we detected 32 fungal species from three phyla (Ascomycota, Basidiomycota, and Zygomycota) and 12 genera. The application of YPG medium and the higher incubation temperature showed higher numbers of isolated fungal species and CFU. Penicillium spp. were dominant in the study, with spores found outside the underground hibernation site from 51.9% to 86.3% and from 56.7% to 100% inside the bat reserve. Penicillium chrysogenum was the most frequently isolated species, then Absidia glauca, Aspergillus fumigatus, A. tubingensis, Mortierella polycephala, Naganishia diffluens, and Rhodotorula mucilaginosa. Temperature, relative humidity, and the abundance of bats correlated positively with the concentration of airborne fungal propagules, between fungal species diversity, and the concentration of aeromycota, but the number of fungal species did not positively correlate with the number of bats. The air in the underground site was more contaminated by fungi than the air outside; however, the concentration of aeromycota does not pose a threat for human health. Nevertheless, hibernating bats contribute to an increase in the aeromycota and as a vector/reservoir of microscopic fungi, including those that may cause allergies and infections in mammals, and should be monitored.

Local Tree Diversity Suppresses Foliar Fungal Infestation and Decreases Morphological But Not Molecular Richness in a Young Subtropical Forest.

Leaf fungal pathogens alter their host species’ performance and, thus, changes in fungal species composition can translate into effects at the tree community scale. Conversely, the functional diversity of tree species in a host tree’s local neighbourhood can affect the host’s foliar fungal infestation. Therefore, understanding the factors that affect fungal infestations is important to advance our understanding of biodiversity-ecosystem functioning (BEF) relationships. Here we make use of the largest BEF tree experiment worldwide, the BEF-China experiment, where we selected tree host species with different neighbour species. Identifying fungal taxa by microscopy and by high-throughput DNA sequencing techniques based on the internal transcribed spacer (ITS) rDNA region, we analysed the fungal richness and infestation rates of our target trees as a function of local species richness. Based on the visual microscopic assessment, we found that a higher tree diversity reduced fungal richness and host-specific fungal infestation in the host’s local neighbourhood, while molecular fungal richness was unaffected. This diversity effect was mainly explained by the decrease in host proportion. Thus, the dilution of host species in the local neighbourhood was the primary mechanism in reducing the fungal disease severity. Overall, our study suggests that diverse forests will suffer less from foliar fungal diseases compared to those with lower diversity.

Diversity of putative ericoid mycorrhizal fungi increases with soil age and progressive phosphorus limitation across a 4.1-million-year chronosequence

Ericaceous plants rely on ericoid mycorrhizal fungi for nutrient acquisition. However, the factors that affect the composition and structure of fungal communities associated with the roots of ericaceous plants remain largely unknown. Here, we use a 4.1-million-year (myr) soil chronosequence in Hawaii to test the hypothesis that changes in nutrient availability with soil age determine the diversity and species composition of fungi associated with ericoid roots. We sampled roots of a native Hawaiian plant, Vaccinium calycinum, and used DNA metabarcoding to quantify changes in fungal diversity and community composition. We also used a fertilization experiment at the youngest and oldest sites to assess the importance of nutrient limitation. We found an increase in diversity and a clear pattern of species turnover across the chronosequence, driven largely by putative ericoid mycorrhizal fungi. Fertilization with nitrogen at the youngest site and phosphorus at the oldest site reduced fungal diversity, suggesting a direct role of nutrient limitation. Our results also reveal the presence of novel fungal species associated with Hawaiian Ericaceae and suggest a greater importance of phosphorus availability for communities of ericoid mycorrhizal fungi than is generally assumed.