The genus Cladosporium

Analyzing Ash Leaf-Colonizing Fungal Communities for Their Biological Control of Hymenoscyphus fraxineus

The invasive ascomycete Hymenoscyphus fraxineus has been threatening Fraxinus excelsior populations throughout Europe for over two decades. Since the infection and first colonization by the pathogen occurs in leaves, leaf-colonizing microorganisms have been discussed as a barrier and as possible biocontrol agents against the disease. To identify fungal groups with health-supporting potential, we compared the fungal microbiota of compound leaves from susceptible and tolerant ash trees in four ash stands with high H. fraxineus exposure. The fungal communities were analyzed both culture-independently by ITS2 amplicon sequencing and by the taxonomic classification of 1,704 isolates using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) or sequencing of the entire ITS region. The fungal community structure did not show significant differences depending on the health status. However, for several OTUs and a MALDI group, a significantly higher abundance was found in tolerant ash trees. Thus, the yeast Papiliotrema flavescens was significantly increased and accounted for 12.3% of the mycobiome of tolerant ashes (OTU0003), and it had also a distinctly higher abundance among the isolates. The filamentous ascomycete Sarocladium strictum was increased 24-fold among the isolates of tolerant trees, but its abundance was comparably low. An in vitro screening for the growth inhibition of the pathogen via cocultivation resulted in 28 yeast-like isolates and 79 filamentous fungi with antagonistic activity. A statistical cocultivation test on two H. fraxineus strains confirmed six of the yeast-like isolates that suppressed H. fraxineus significantly, from 39-50%, two of them through a fungicidal effect. The highest inhibition rates among the yeasts were found for three isolates belonging to Aureobasidium pullulans and P. flavescens. The cocultivation test of the filamentous isolates revealed higher effects compared to the yeasts. Four isolates showed significant inhibition of both H. fraxineus strains with a rate of 72-100%, and five further isolates inhibited only one H. fraxineus strain significantly. The most effective isolates were members of the genus Cladosporium. During the next step, in planta tests will be necessary to verify the efficacy of the antagonistic isolates and to assess their suitability as biocontrol agents.

Pathobiomes Revealed that Pseudomonas fuscovaginae and Sarocladium oryzae Are Independently Associated with Rice Sheath Rot

Rice sheath rot has been mainly associated with the bacterial pathogen Pseudomonas fuscovaginae and in some cases to the fungal pathogen Sarocladium oryzae; it is yet unclear if they are part of a complex disease. The bacterial and fungal community associated with rice sheath rot symptomatic and asymptomatic rice plants was determined/studied with the main aim to shed light on the pathogen(s) causing rice sheath rot. Plant samples were collected from different rice varieties in two locations (highland and lowland) in two rice-growing seasons (wet and dry season) in Burundi. Our results showed that the bacterial Pseudomonas genus was prevalent in highland in both rice-growing seasons and was not affected by rice plant varieties. Pseudomonas sequence reads displayed a significant high similarity to Pseudomonas fuscovaginae indicating that it is the causal agent of rice sheath rot as previously reported. The fungal Sarocladium genus was on the other hand prevalent in lowland only in the wet season; the sequence reads were most significantly similar to Sarocladium oryzae. These studies showed that plant microbiome analysis is very useful in determining the microorganisms involved in a plant disease. P. fuscovaginae and S. oryzae were prevalent in symptomatic samples in highland and lowland respectively being present independently and hence are not part of a complex disease. The significant presence of other bacterial and fungal taxa in symptomatic samples is also discussed possibly making this disease more complex. Finally, we also report the microbial communities that are associated with the plant sheath in symptomatic and asymptomatic plants from the same rice fields.

One stop shop IV: taxonomic update with molecular phylogeny for important phytopathogenic genera: 76–100 (2020)

This is a continuation of a series focused on providing a stable platform for the taxonomy of phytopathogenic fungi and fungus-like organisms. This paper focuses on one family: Erysiphaceae and 24 phytopathogenic genera: Armillaria, Barriopsis, Cercospora, Cladosporium, Clinoconidium, Colletotrichum, Cylindrocladiella, Dothidotthia,, Fomitopsis, Ganoderma, Golovinomyces, Heterobasidium, Meliola, Mucor, Neoerysiphe, Nothophoma, Phellinus, Phytophthora, Pseudoseptoria, Pythium, Rhizopus, Stemphylium, Thyrostroma and Wojnowiciella. Each genus is provided with a taxonomic background, distribution, hosts, disease symptoms, and updated backbone trees. Species confirmed with pathogenicity studies are denoted when data are available. Six of the genera are updated from previous entries as many new species have been described.

Production and partial purification by PEG/citrate ATPS of a β-galactosidase from the new promising isolate Cladosporium tenuissimum URM 7803

β-Galactosidase production, partial purification and characterization by a new fungal were investigated. Partial purification was performed by aqueous two-phase system (ATPS) using polyethylene glycol (PEG) molar mass, PEG concentration, citrate concentration and pH as the independent variables. Purification factor (PF), partition coefficient (K) and yield (Y) were the responses. After identification by rDNA sequencing and classification as Cladosporium tenuissimum URM 7803, this isolate achieved a maximum cell concentration and β-galactosidase activity of 0.48 g/L and 462.1 U/mL, respectively. β-Galactosidase partitioned preferentially for bottom salt-rich phase likely due to hydrophobicity and volume exclusion effect caused in the top phase by the high PEG concentration and molar mass. The highest value of PF (12.94) was obtained using 24% (w/w) PEG 8000 g/mol and 15% (w/w) citrate, while that of Y (79.76%) using 20% (w/w) PEG 400 g/mol and 25% (w/w) citrate, both at pH 6. The enzyme exhibited optimum temperature in crude and ATPS extracts in the ranges 35-50 °C and 40-55 °C, respectively, and optimum pH in the range 3.0-4.5, with a fall of enzyme activity under alkaline conditions. Some metal ions and detergents inhibited, while others stimulated enzyme activity. Finally, C. tenuissimum URM 7803 β-galactosidase showed a profile suitable for prebiotics production.

A Culture-Based ID of Micromycetes on the Wing Membranes of Greater Mouse-Eared Bats (Myotis myotis) from the "Nietoperek" Site (Poland)

Bats play important functions in ecosystems and many of them are threatened with extinction. Thus, the monitoring of the health status and prevention of diseases seem to be important aspects of welfare and conservation of these mammals. The main goal of the study was the identification of culturable fungal species colonizing the wing membranes of female greater mouse-eared bat (Myotis myotis) during spring emergence from the "Nietoperek" underground hibernation site by the use of genetic and phenotypic analyses. The study site is situated in Western Poland (52°25' N, 15°32' E) and is ranked within the top 10 largest hibernation sites in the European Union. The number of hibernating bats in the winter exceeds 39,000 individuals of 12 species, with M. myotis being the most common one. The wing membranes of M. myotis were sampled using sterile swabs wetted in physiological saline (0.85% NaCl). Potato dextrose agar (PDA) plates were incubated in the dark at 8, 24 and 36 ± 1 °C for 3 up to 42 days. All fungi isolated from the surface of wing membranes were assigned to 17 distinct fungal isolates belonging to 17 fungal species. Penicillium chrysogenum was the most frequently isolated species. Some of these fungal species might have a pathogenic potential for bats and other mammals. However, taking into account habitat preferences and the life cycle of bats, it can be assumed that some fungi were accidentally obtained from the surface of vegetation during early spring activity. Moreover, Pseudogymnoascus destructans (Pd)-the causative agent of the White Nose Syndrome (WNS)-was not found during testing, despite it was found very often in M. myotis during previous studies in this same location.

Populations of the Parasitic Plant Phelipanche ramosa Influence Their Seed Microbiota

Seeds of the parasitic weed Phelipanche ramosa are well adapted to their hosts because they germinate and form haustorial structures to connect to roots in response to diverse host-derived molecular signals. P. ramosa presents different genetic groups that are preferentially adapted to certain hosts. Since there are indications that microbes play a role in the interaction especially in the early stages of the interaction, we studied the microbial diversity harbored by the parasitic seeds with respect to their host and genetic group. Twenty-six seed lots from seven cropping plots of three different hosts-oilseed rape, tobacco, and hemp-in the west of France were characterized for their bacterial and fungal communities using 16S rRNA gene and ITS (Internal transcribed spacer) sequences, respectively. First seeds were characterized genetically using twenty microsatellite markers and phenotyped for their sensibility to various germination stimulants including strigolactones and isothiocyanates. This led to the distinction of three P. ramosa groups that corresponded to their host of origin. The observed seed diversity was correlated to the host specialization and germination stimulant sensitivity within P. ramosa species. Microbial communities were both clustered by host and plot of origin. The seed core microbiota was composed of seventeen species that were also retrieved from soil and was in lower abundances for bacteria and similar abundances for fungi compared to seeds. The host-related core microbiota of parasitic seeds was limited and presumably well adapted to the interaction with its hosts. Two microbial candidates of Sphingobacterium species and Leptosphaeria maculans were especially identified in seeds from oilseed rape plots, suggesting their involvement in host recognition and specialization as well as seed fitness for P. ramosa by improving the production of isothiocyanates from glucosinolates in the rhizosphere of oilseed rape.

A Compost Treatment Acts as a Suppressive Agent in Phytophthora capsici - Cucurbita pepo Pathosystem by Modifying the Rhizosphere Microbiota

Phytophthora capsici Leonian (PHC) is a filamentous pathogen oomycete that causes root, fruit, foliar and crown rot over a wide host range, including the economically and nutritionally important summer squash (Cucurbita pepo var. cylindrica L.) crop. PHC chemical control strategies are difficult to adopt, due to the limited number of registered chemicals that are permitted and the scalar harvest system. For these reasons, other strategies, such as the use of waste-based composts that can act as suppressive agents against several soilborne pathogens, have been studied intensively. It is well known that compost's microbiota plays an important role to confer its suppressive ability. In this study, four different composts were analyzed with both 16S rRNA gene and 18S rRNA gene real-time PCR amplification and with 26S gene amplicon-based sequencing; the total abundance of the bacterial and fungal communities was found to be higher compared to literature, thus confirming that the four composts were a good inoculum source for agricultural applications. The core mycobiota was mainly composed of 31 genera; nevertheless, it was possible to observe a clear predominance of the same few taxa in all the composts. The four composts were then tested, at different concentrations (1-10-20% v/v), to establish their ability to confer suppressiveness to the Phytophthora capsici (PHC) - Cucurbita pepo pathosystem in controlled greenhouse pot trials. A total of 12 compost mixtures were considered, and of these, one (Trichoderma-enriched compost at 10% v/v) was able to statistically reduce the disease incidence caused by PHC (by 50% compared to the untreated control). Hence, the microbiota composition of the most effective compost treatment was investigated and compared with untreated and chemical (metalaxyl) controls. Mycobiota sequencing showed genera differences between the three treatments, with relative abundances of several fungal genera that were significantly different among the samples. Moreover, PCA analyses clustered the compost treatment differently from the chemical and the untreated controls. These findings suggest that suppressive activity of a compost is strictly influenced by its microbiota and the applied dosage, but the ability to induce a shaping in the rhizosphere microbial composition is also required.

Cladosporium species causing "Cladosporium rot" on "Bosc" pear fruit in Argentina

"Cladosporium rot" on "Bosc" pear fruit during cold storage causes significant economic losses and has been reported in recent years in the productive valleys of Río Negro and Neuquén. The species involved were not determined. During 2016-2017, "Bosc" pears (Pyrus communis) in cold storage chambers exhibited external brownish black circular spots caused by Cladosporium spp. The objective of this work was to determine the Cladosporium species that caused the above mentioned symptoms. The morphological and molecular analyses of the partial sequence of the actin gene (ACT) supported the identification. Cladosporium macrocarpum, Cladosporium subtilissimum and Cladosporium floccosum were determined as the species involved in the disease. Although Cladosporium has been reported to cause pear rot, this is the first report to identify these species as causal agents of this fruit disease.

Problems, Limitations, and Challenges in Species Identification of Ascomycota Members on the Basis of ITS Regions

The internal transcribed spacer (ITS) region is regarded as a formal fungal primary barcode with a high probability of the correct identification for a broad group of fungi. ITS sequences have been widely used to determine many fungal species and analysis of rDNA ITS is still one of the most popular tools used in mycology. However, this region is not equally variable in all groups of fungi; therefore, identification may be problematic and result in ambiguous data, especially in some species-rich genera of Ascomycota. For these reasons, identification based on rDNA ITS is usually complemented by morphological observations and analysis of additional genes. Reliable species identification of Ascomycota members is essential in diagnosing plant diseases, verifying air quality and the effectiveness of agronomic practices, or analyzing relationships between microorganisms. Therefore, the present study aimed to verify, using specific examples, the extent to which ITS sequence analysis is useful in species identification of pathogens and saprobionts from Ascomycota and demonstrate problems related to such identification in practice. We analyzed 105 ITS sequences of isolates originating from air and plant material. Basic local alignment search tool (BLASTn) significantly contributed to the reliable species identification of nearly 80% of isolates such as <em>Arthrinium arundinis</em>, <em>Beauveria bassiana</em>, <em>Boeremia exigua</em>, <em>Cladosporium cladosporioides</em>, <em>Epicoccum nigrum</em>, <em>Nigrospora oryzae</em>, <em>Sclerotinia sclerotiorum</em>, or <em>Sordaria fimicola </em>and members of the genera <em>Alternaria </em>and <em>Trichoderma</em>. However, for most isolates, additional morphological observations, information regarding the isolate origin and, where possible, a PCR with species-specific primers were helpful and complementary. Using our practical approach, we determined that ITS-based species identification and comparative analysis with GenBank sequences significantly helps identifying Ascomycota members. However, in many cases, this should be regarded as suggestive of a taxon because the data usually require the use of additional tools to verify the results of such analysis.

Temporal Dynamics of the Gut Bacteriome and Mycobiome in the Weanling Pig

Weaning is a period of environmental changes and stress that results in significant alterations to the piglet gut microbiome and is associated with a predisposition to disease, making potential interventions of interest to the swine industry. In other animals, interactions between the bacteriome and mycobiome can result in altered nutrient absorption and susceptibility to disease, but these interactions remain poorly understood in pigs. Recently, we assessed the colonization dynamics of fungi and bacteria in the gastrointestinal tract of piglets at a single time point post-weaning (day 35) and inferred interactions were found between fungal and bacterial members of the porcine gut ecosystem. In this study, we performed a longitudinal assessment of the fecal bacteriome and mycobiome of piglets from birth through the weaning transition. Piglet feces in this study showed a dramatic shift over time in the bacterial and fungal communities, as well as an increase in network connectivity between the two kingdoms. The piglet fecal bacteriome showed a relatively stable and predictable pattern of development from Bacteroidaceae to Prevotellaceae, as seen in other studies, while the mycobiome demonstrated a loss in diversity over time with a post-weaning population dominated by Saccharomycetaceae. The mycobiome demonstrated a more transient community that is likely driven by factors such as diet or environmental exposure rather than an organized pattern of colonization and succession evidenced by fecal sample taxonomic clustering with nursey feed samples post-weaning. Due to the potential tractability of the community, the mycobiome may be a viable candidate for potential microbial interventions that will alter piglet health and growth during the weaning transition.

Diversity of Filamentous Fungi Isolated From Some Amylase and Alcohol-Producing Starters of India

Filamentous fungi are important organisms in traditionally prepared amylase and alcohol-producing dry starters in India. We collected 40 diverse types of amylase and alcohol-producing starters from eight states in North East India viz. marcha, thiat, humao, hamei, chowan, phut, dawdim, and khekhrii. The average fungal population was 4.9 × 10⁵ cfu/g with an average of pH 5.3 and 10.7%, respectively. In the present study, 131 fungal isolates were isolated and characterized based on macroscopic and microscopic characteristics and were grouped into 44 representative fungal strains. Based on results of morphological characteristics and ITS gene sequencing, 44 fungal strains were grouped into three phyla represented by Ascomycota (48%), Mucoromycota (38%), and Basidiomycota (14%). Taxonomical keys to species level was illustrated on the basis of morphological characteristics and ITS gene sequencing, aligned to the fungal database of NCBI GenBank, which showed seven genera with 16 species represented by Mucor circinelloides (20%), Aspergillus sydowii (11%), Penicillium chrysogenum (11%), Bjerkandera adusta (11%), Penicillium citrinum (7%), Rhizopus oryzae (7%), Aspergillus niger (5%), Aspergillus flavus (5%), Mucor indicus (5%) Rhizopus microsporus (5%), Rhizopus delemar (2%), Aspergillus versicolor (2%), Penicillium oxalicum (2%), Penicillium polonicum (2%), Trametes hirsuta (2%), and Cladosporium parahalotolerans (2%). The highest Shannon diversity index H was recorded in marcha of Sikkim (H: 1.74) and the lowest in hamei of Manipur (H: 0.69). Fungal species present in these amylolytic starters are morphologically, ecologically and phylogenetically diverse and showed high diversity within the community.

Microbiome of the Queensland Fruit Fly through Metamorphosis

Bactrocera tryoni (Froggatt) (Queensland fruit fly, or “Qfly”) is a highly polyphagous tephritid fruit fly and a serious economic pest in Australia. Qfly biology is intimately linked to the bacteria and fungi of its microbiome. While there are numerous studies of the microbiome in larvae and adults, the transition of the microbiome through the pupal stage remains unknown. To address this knowledge gap, we used high-throughput Next-Generation Sequencing (NGS) to examine microbial communities at each developmental stage in the Qfly life cycle, targeting the bacterial 16S rRNA and fungal ITS regions. We found that microbial communities were similar at the larval and pupal stage and were also similar between adult males and females, yet there were marked differences between the larval and adult stages. Specific bacterial and fungal taxa are present in the larvae and adults (fed hydrolyzed yeast with sugar) which is likely related to differences in nutritional biology of these life stages. We observed a significant abundance of the Acetobacteraceae at the family level, both in the larval and pupal stages. Conversely, Enterobacteriaceae was highly abundant (>80%) only in the adults. The majority of fungal taxa present in Qfly were yeasts or yeast-like fungi. In addition to elucidating changes in the microbiome through developmental stages, this study characterizes the Qfly microbiome present at the establishment of laboratory colonies as they enter the domestication process.

Production and characterization of melanin pigments derived from Amorphotheca resinae

As melanin has emerged as functional pigment with cosmetic, health and food applications, the demand for the pigments is expected to increase. However, the conventional sources (e.g. mushroom, hair, and wool) of melanin production entail pigments inside the substrates which requires the costly extraction procedures, leading to inappropriate scalable production. In this study, we screened 102 of fungal isolates for their ability to produce melanin in the supernatant and selected the only Amorphotheca resinae as a promising candidate. In the peptone yeast extract glucose broth, A. resinae produced the melanin rapidly during the autolysis phase of growth, reaching up 4.5 g/L within 14 days. Structural characterization of the purified melanin from A. resinae was carried out by using elemental analysis, electron paramagnetic resonance, ¹³C solid-state nuclear magnetic resonance spectroscopy, and pyrolysis-gas chromatography-mass spectrometry in comparison with the standard melanins. The results indicate that the structural properties of A. resinae melanin is similar to the eumelanin which has a wide range of industrial uses. For example, the purified melanin from A. resinae has the potent antioxidant activities as a result of free radical scavenging assays. Consequently, A. resinae KUC3009 can be a promising candidate for scalable production of industrially applicable melanin.

The establishment of a fungal consortium in a new winery

The biodiversity and evolution of fungal communities were monitored over a period of 3 vintages in a new winery. Samples were collected before grape receipt and 3 months after fermentation from 3 different wine related environments (WRE): floor, walls and equipment and analyzed using Illumina Mi-Seq. Genera of mold and filamentous fungi (294), non-enological (10) and wine-associated yeasts (25) were detected on all WREs before the arrival of the first harvest. Among them, genera like Alternaria and Aureobasidium persisted during two vintages. Therefore, these genera are not specific to winery environment and appear to be adapted to natural or anthropic environments due to their ubiquitous character. Some genera like Candida were also detected before the first harvest but only on one WREs, whereas, on the other WREs they were found after the harvest. The ubiquitous character and phenotypic traits of these fungal genera can explain their dynamics. After the first harvest and during 3 vintages the initial consortium was enriched by oenological genera like Starmerella introduced either by harvest or by potential transfers between the different WREs. However, these establishing genera, including Saccharomyces, do not appear to persist due to their low adaptation to the stressful conditions of winery environment.

Current challenges for shaping the sustainable and mold-free hygienic indoor environment in humid regions

Indoor mold grows ubiquitously in humid areas and can affect occupants' health. To prevent indoor mold contamination, one of the key measures suggested by the World Health Organisation and United States Environmental Protection Agency is to maintain an indoor relative humidity (RH) level below 75% or at 30-60%, respectively. However, in tropical and subtropical areas, maintaining these suggested RH levels is equivalent to operating a 24-h air-conditioner (AC) or dehumidifier, which is energy-consuming. As a large part of building expense, the operation time of ACs has been regularly proposed to be cut down because of the requirement of building sustainability. This leads to a trade-off between sustainable building performance and indoor mold hygiene. To balance this trade-off, more sustainable alternatives, such as those that target physical environments (e.g. nutrient and temperature level) or apply new surface coating technologies to inhibit mold growth, have been launched. Despite these initiatives, indoor mold contamination remains an unresolved issue, mainly because these alternative measures only exhibit limited effectiveness or require extra effort. This review aims to summarize the currently adopted mold control measures and discuss their limitations as well as the direction for the future development of sustainable mold control strategies. SIGNIFICANCE AND IMPACT OF THE STUDY: People spend most of their time indoors and hence the presence of indoor mold contamination can compromise the occupants' health. With the wake of climate change which is expected to see an increase in RH and temperature, tropical and subtropical areas are even more prone to mold contamination than they used to be. This study may help facilitate the development of sustainable and effective mold control strategies in the indoor environment.

Epidemiology of Dermatophyte and Non-Dermatophyte Fungi Infection in Ethiopia

Background

Dermatophytosis represents one of the common infectious diseases worldwide and it is a major public health problem around the globe. The disease causes considerable morbidity and still continues to increase especially in developing countries.

Objective

This study was undertaken to determine the prevalence of dermatophytes and the spectrum of fungal agents in patients attending Rank Higher Specialized Dermatology Clinic.

Methods

A cross-sectional study has been conducted, in which 318 samples from 318 suspected patients were collected. Samples include hair, nail, and skin. A portion of each sample was examined microscopically and the remaining portion of each sample was cultured onto plates of Sabouraud's dextrose agar containing chloramphenicol with and without cycloheximide. Isolates were identified by studying the macroscopic and microscopic characteristics of the colonies.

Results

Tinea capitis was the predominant clinical manifestation accounting for 53.4% of the cases. Patients with age group 1-14 years were more affected. Of 318 samples, fungi were detected in 133 (54.4%) by direct wet mount while 148/315 (46.5%) of them were culture positive. From these 72/148 (46.8%) were dermatophytes. T. tonsurans was the most common pathogen in tinea capitis, whereas T. mentagrophytes was the most common pathogen in tinea corporis. Among dermatophyte isolates, T. tonsurans 29/72 (40.2%) was the most common cause of infection. Among non-dermatophyte molds, Cladosporiumspp. 21/63 (33.3%) was predominant isolate followed by Neoscytalidim dimidatum 11/63 (17.4%) and Alternariaspp. 9/63 (14.2%), respectively. Yeasts also account for 13 (8.7%) of the total suspects of dermatophytosis.

Conclusion

In this study, the prevalence of dermatophytes was higher in tinea capitis 46/72 (63.8%) and T. tonsurans 29/72 (40%) was the dominant-isolated dermatophyte. Recovery of a large number of dermatophytes and non-dermatophyte fungi in our study showed that non-dermatophyte fungi are emerging as important causes of dermatophytosis warranting further intensive epidemiological studies that have public health significance are needed.

An In Vitro Pipeline for Screening and Selection of Citrus-Associated Microbiota with Potential Anti-"Candidatus Liberibacter asiaticus" Properties

Huanglongbing (HLB) is a destructive citrus disease that is lethal to all commercial citrus plants, making it the most serious citrus disease and one of the most serious plant diseases. Because of the severity of HLB and the paucity of effective control measures, we structured this study to encompass the entirety of the citrus microbiome and the chemistries associated with that microbial community. We describe the spatial niche diversity of bacteria and fungi associated with citrus roots, stems, and leaves using traditional microbial culturing integrated with culture-independent methods. Using the culturable sector of the citrus microbiome, we created a microbial repository using a high-throughput bulk culturing and microbial identification pipeline. We integrated an in vitro agar diffusion inhibition bioassay into our culturing pipeline that queried the repository for antimicrobial activity against Liberibacter crescens, a culturable surrogate for the nonculturable "Candidatus Liberibacter asiaticus" bacterium associated with HLB. We identified microbes with robust inhibitory activity against L. crescens that include the fungi Cladosporium cladosporioides and Epicoccum nigrum and bacterial species of Pantoea, Bacillus, and Curtobacterium Purified bioactive natural products with anti-"Ca. Liberibacter asiaticus" activity were identified from the fungus C. cladosporioides Bioassay-guided fractionation of an organic extract of C. cladosporioides yielded the natural products cladosporols A, C, and D as the active agents against L. crescens This work serves as a foundation for unraveling the complex chemistries associated with the citrus microbiome to begin to understand the functional roles of members of the microbiome, with the long-term goal of developing anti-"Ca Liberibacter asiaticus" bioinoculants that thrive in the citrus holosystem.IMPORTANCE Globally, citrus is threatened by huanglongbing (HLB), and the lack of effective control measures is a major concern of farmers, markets, and consumers. There is compelling evidence that plant health is a function of the activities of the plant's associated microbiome. Using Liberibacter crescens, a culturable surrogate for the unculturable HLB-associated bacterium "Candidatus Liberibacter asiaticus," we tested the hypothesis that members of the citrus microbiome produce potential anti-"Ca Liberibacter asiaticus" natural products with potential anti-"Ca Liberibacter asiaticus" activity. A subset of isolates obtained from the microbiome inhibited L. crescens growth in an agar diffusion inhibition assay. Further fractionation experiments linked the inhibitory activity of the fungus Cladosporium cladosporioides to the fungus-produced natural products cladosporols A, C, and D, demonstrating dose-dependent antagonism to L. crescens.

Gene expression changes in human bronchial epithelial cells (BEAS-2B) and human pulmonary alveolar epithelial cells (HPAEpiC) after interaction with Cladosporium sphaerospermum

Cladosporium is one of the most abundant spore. Fungi of this genus can cause respiratory allergy and intrabronchial lesion. We studied the differential expression of host genes after the interaction of Cladosporium sphaerospermum conidia with Human Bronchial Epithelial Cells (BEAS-2B) and Human Pulmonary Alveolar Epithelial Cells (HPAEpiC). C. sphaerospermum conidia were harvested and co-cultured with BEAS-2B cells or HPAEpiC cells for 48 hours respectively. This culture duration was chosen as it was associated with high germination rate. RNA was extracted from two biological replicates per treatment. RNA of BEAS-2B cells was used to assess changes in gene expression using AffymetrixGeneChip® Human Transcriptome Array 2.0. After co-culture with Cladosporium spores, 68 individual genes were found differentially expressed (P ≤ 0.05) and up-regulated ≥ 1.5 folds while 75 genes were found differentially expressed at ≤ -1.5 folds compared with controls. Reverse transcription and qPCR were performed on the RNA collected from both BEAS-2B cells and HPAEpiC cells to validate the microarray results with 7 genes. Based on the findings, infected pulmonary epithelial cells exhibited an increase in cell death-related genes and genes associated with innate immunity.

Agroforestry Management Systems Drive the Composition, Diversity, and Function of Fungal and Bacterial Endophyte Communities in Theobroma Cacao Leaves

Cacao (Theobroma cacao L.) is one of the most economically important crops worldwide. Despite the important role of endophytes for plant growth and health, very little is known about the effect of agroforestry management systems on the endophyte communities of T. cacao. To close this knowledge gap, we investigated the diversity, community composition, and function of bacterial and fungal endophytes in the leaves of T. cacao trees growing in five major cacao-growing regions in the central region of Cameroon using DNA metabarcoding. Fungal but not bacterial alpha diversity measures differed significantly between the agroforestry management systems. Interestingly, less managed home-garden cacao forests harbored the lowest fungal richness and diversity. Our results suggest that the composition of bacterial and fungal endophyte communities is predominantly affected by agroforestry management systems and, to a lesser extent, by environmental properties. The core microbiome detected comprised important fungal phytopathogens, such as Lasiodiplodia species. Several predicted pathways of bacterial endophytes and functional guilds of fungal endophytes differed between the agroforest systems which might be attributed to bacteria and fungi specifically associated with a single agroforest. Our results provide the basis for future studies on foliar fungal and bacterial endophytes of T. cacao and their responsiveness towards agroforestry management systems.

Occurrence of Fungi and Fungal Toxins in Fish Feed During Storage

Periods of unfavorable storing conditions can lead to changes in the quality of fish feeds, as well as the development of relevant mycotoxins. In the present study, a commercial fish feed was stored under defined conditions for four weeks. The main findings indicate that even storing fish feeds under unsuitable conditions for a short duration leads to a deterioration in quality. Mycotoxin and fungal contamination were subsequently analyzed. These investigations confirmed that different storage conditions can influence the presence of fungi and mycotoxins on fish feed. Notably, ochratoxin A (OTA) was found in samples after warm (25 °C) and humid (>60% relative humidity) treatment. This confirms the importance of this compound as a typical contaminant of fish feed and reveals how fast this mycotoxin can be formed in fish feed during storage.

Aspergillus, Penicillium and Cladosporium species associated with dried date fruits collected in the Perugia (Umbria, Central Italy) market

A total of 20 dried date samples, chosen as representative among those available on the Perugia (Umbria, Central Italy) market, were analyzed for the possible occurrence of fungal species and related contamination by fungal secondary metabolites. Twenty-six isolates, representative of the total mycobiota, were obtained and morphologically identified as belonging to the genera Aspergillus, Penicillium and Cladosporium. Inside each genus, molecular characterization (by partial sequencing of ITS region and/or β-tubulin and calmodulin regions for Aspergillus and Penicillium isolates or actin region for Cladosporium isolates) and in vitro mycotoxigenic profile characterization (by LC-MS/MS analysis) showed the presence of the following species: A. flavus, A. tubingensis, P. brevicompactum, P. chrysogenum, P. crustosum, P. glabrum, P. solitum, P. venetum, C. cladosporioides, C. limoniforme and C. halotolerans, with A. tubingensis as the prevalent species and P. crustosum, P. solitum, P. venetum and C. limoniforme first reported here on dates. Date packaging and format showed an effect on the incidence of isolated fungi, with the lowest incidence recovered from whole dates and in hermetic bag packaging. These findings can be useful both for dried dates producers and consumers, guiding them towards choices of packaging and format with a lower risk of mycotoxigenic species presence. However, no fungal metabolites were detected in the dried date samples analyzed, which were therefore regarded as safe for human consumption, underlining the absence of correspondence between fungal isolation and mycotoxin contaminations.

Evolution of lifestyles in Capnodiales

The Capnodiales, which includes fungi known as the sooty moulds, represents the second largest order in Dothideomycetes, encompassing morphologically and ecologically diverse fungi with different lifestyles and modes of nutrition. They include saprobes, plant and human pathogens, mycoparasites, rock-inhabiting fungi (RIF), lichenised, epi-, ecto- and endophytes. The aim of this study was to elucidate the lifestyles and evolutionary patterns of the Capnodiales as well as to reconsider their phylogeny by including numerous new collections of sooty moulds, and using four nuclear loci, LSU, ITS, TEF-1α and RPB2. Based on the phylogenetic results, combined with morphology and ecology, Capnodiales s. lat. is shown to be polyphyletic, representing seven different orders. The sooty moulds are restricted to Capnodiales s. str., while Mycosphaerellales is resurrected, and five new orders including Cladosporiales, Comminutisporales, Neophaeothecales, Phaeothecales and Racodiales are introduced. Four families, three genera, 21 species and five combinations are introduced as new. Furthermore, ancestral reconstruction analysis revealed that the saprobic lifestyle is a primitive state in Capnodiales s. lat., and that several transitions have occurred to evolve lichenised, plant and human parasitic, ectophytic (sooty blotch and flyspeck) and more recently epiphytic (sooty mould) lifestyles.

Different Dynamics of Bacterial and Fungal Communities in Hive-Stored Bee Bread and Their Possible Roles: A Case Study from Two Commercial Honey Bees in China

This study investigated both bacterial and fungal communities in corbicular pollen and hive-stored bee bread of two commercial honey bees, Apis mellifera and Apis cerana, in China. Although both honey bees favor different main floral sources, the dynamics of each microbial community is similar. During pH reduction in hive-stored bee bread, results from conventional culturable methods and next-generation sequencing showed a declining bacterial population but a stable fungal population. Different honey bee species and floral sources might not affect the core microbial community structure but could change the number of bacteria. Corbicular pollen was colonized by the Enterobacteriaceae bacterium (Escherichia-Shiga, Panteoa, Pseudomonas) group; however, the number of bacteria significantly decreased in hive-stored bee bread in less than 72 h. In contrast, Acinetobacter was highly abundant and could utilize protein sources. In terms of the fungal community, the genus Cladosporium remained abundant in both corbicular pollen and hive-stored bee bread. This filamentous fungus might encourage honey bees to reserve pollen by releasing organic acids. Furthermore, several filamentous fungi had the potential to inhibit both commensal/contaminant bacteria and the growth of pathogens. Filamentous fungi, in particular, the genus Cladosporium, could support pollen preservation of both honey bee species.

Changes of Quality of Minimally-Processed Pineapple (Ananas comosus, var. 'Queen Victoria') during Cold Storage: Fungi in the Leading Role

Minimally-processed pineapple stored under refrigerated conditions is highly perishable. We aimed to characterize the evolution of physicochemical, sensory and microbiological quality during cold storage. Pineapple batches were sampled from several locations in Reunion Island and then minimally processed. In the processing step, the variability of firmness and counts of yeasts and molds were observed. Moreover, correlations between the sampling season and pH and b* color component, as well as between fungal population and b* parameter were observed. During storage, the visual aspect of pineapple cuts changed to brown and shiny, whereas olfactive descriptors shifted from fruity descriptors and fresh to fermented, alcoholic and milky. The values for pH, TA and TSS did not significantly vary according to storage time. A decrease in firmness and C* color parameter was observed. Yeast and mold counts were significantly higher after 7 days of storage. The diversity in yeasts and molds was mainly dependent on the considered batches observed from PCR-DGGE profiles. Fungal species were isolated from spoiled pineapple cuts. The implication of Penicilllium citrtrinum, Talaromyces amestolkiae, Rhodotorula mucilaginosa, Saccharomyces cerevisiae, and Meyerozyma caribbica in the spoilage of minimally-processed pineapple cuts was further demonstrated.

Isolation and identification of L-asparaginase-producing endophytic fungi from the Asteraceae family plant species of Iran

L-asparaginase is an important anticancer enzyme that is used in the first line treatment of acute lymphoblastic leukemia. This study was conducted to isolate L-asparaginase-producing endophytic fungi from medicinal plants of family Asteraceae. Seven healthy medicinal plants from family Asteraceae were selected for the isolation of endophytic fungi using standard surface sterilization techniques. A total of 837 isolates belonging to 84 species were comprised of the stem (55.6%), leaf (31.1%), root (10.6%) and flower (2.7%). Initial screening of L-asparaginase-producing endophytes was performed by qualitative plate assay on modified Czapex dox’s agar medium. L-asparaginase activity of fungal endophytes was quantified by the nesslerization method. Identification of endophytic fungi was performed using both morphological characteristics and phylogenetic analyses of DNA sequence data including ribosomal DNA regions of ITS (Internal transcribed spacer) and LSU (partial large subunit rDNA), TEF1 (Translation Elongation Factor) and TUB (β-tubulin). Of the 84 isolates, 38 were able to produce L-asparaginase and their L-asparaginase activities were between 0.019 and 0.492 unit/mL with Fusarium proliferatum being the most potent. L-asparaginase-producing endophytes were identified as species of Plectosphaerella, Fusarium, Stemphylium, Septoria, Alternaria, Didymella, Phoma, Chaetosphaeronema, Sarocladium, Nemania, Epicoccum, Ulocladium and Cladosporium. This study showed that endophytic fungi from Asteraceae members have a high L-asparaginase-producing potential and they can be used as an alternative source for production of anticancer enzymes.

The role of oxidative stress in the growth of the indoor mold Cladosporium cladosporioides under water dynamics

Moisture is one of the critical abiotic factors that can affect mold growth. Indoor humidity is typically fluctuating, which renders a transient water supply for mold growth. Understanding mold growth under water dynamics and its underlying mechanisms can help in the development of novel and sustainable mold prevention strategies. In this study, pre-germination and germinated spores of Cladosporium cladosporioides were exposed to daily wet-dry cycles with different combinations of wetting and drying duration. Afterward, growth delay, cellular H₂ O₂ concentration, and catalase (CAT) activity were measured and compared. We found that under daily wet-dry cycles, the longer the growth delay was observed, the higher the cellular H₂ O₂ concentration was detected, with the 12-12 wet-dry cycle (12-hour wet and 12-hour dry) showing the longest growth delay and highest cellular H₂ O₂ production. A positive correlation between cellular H₂ O₂ concentration and growth delay was suggested by Pearson correlation coefficient and linear regression analysis (P < .0001, R²  = 0.85). Furthermore, under daily wet-dry cycles, molds derived from pre-germination spores generally exhibited shorter growth delay, lower cellular H₂ O₂ concentration, and higher CAT activity than molds developed from germinated spores. These results together suggest that the growth delay of C. cladosporioides under water dynamics is associated with oxidative stress.

Fungal Planet description sheets: 951-1041

Novel species of fungi described in this study include those from various countries as follows: Antarctica, Apenidiella antarctica from permafrost, Cladosporium fildesense from an unidentified marine sponge. Argentina, Geastrum wrightii on humus in mixed forest. Australia, Golovinomyces glandulariae on Glandularia aristigera, Neoanungitea eucalyptorum on leaves of Eucalyptus grandis, Teratosphaeria corymbiicola on leaves of Corymbia ficifolia, Xylaria eucalypti on leaves of Eucalyptus radiata. Brazil, Bovista psammophila on soil, Fusarium awaxy on rotten stalks of Zea mays, Geastrum lanuginosum on leaf litter covered soil, Hermetothecium mikaniae-micranthae (incl. Hermetothecium gen. nov.) on Mikania micrantha, Penicillium reconvexovelosoi in soil, Stagonosporopsis vannaccii from pod of Glycine max. British Virgin Isles, Lactifluus guanensis on soil. Canada, Sorocybe oblongispora on resin of Picea rubens. Chile, Colletotrichum roseum on leaves of Lapageria rosea. China, Setophoma caverna from carbonatite in Karst cave. Colombia, Lareunionomyces eucalypticola on leaves of Eucalyptus grandis. Costa Rica, Psathyrella pivae on wood. Cyprus, Clavulina iris on calcareous substrate. France, Chromosera ambigua and Clavulina iris var. occidentalis on soil. French West Indies, Helminthosphaeria hispidissima on dead wood. Guatemala, Talaromyces guatemalensis in soil. Malaysia, Neotracylla pini (incl. Tracyllales ord. nov. and Neotracylla gen. nov.) and Vermiculariopsiella pini on needles of Pinus tecunumanii. New Zealand, Neoconiothyrium viticola on stems of Vitis vinifera, Parafenestella pittospori on Pittosporum tenuifolium, Pilidium novae-zelandiae on Phoenix sp. Pakistan, Russula quercus-floribundae on forest floor. Portugal, Trichoderma aestuarinum from saline water. Russia, Pluteus liliputianus on fallen branch of deciduous tree, Pluteus spurius on decaying deciduous wood or soil. South Africa, Alloconiothyrium encephalarti, Phyllosticta encephalarticola and Neothyrostroma encephalarti (incl. Neothyrostroma gen. nov.) on leaves of Encephalartos sp., Chalara eucalypticola on leaf spots of Eucalyptus grandis × urophylla, Clypeosphaeria oleae on leaves of Olea capensis, Cylindrocladiella postalofficium on leaf litter of Sideroxylon inerme, Cylindromonium eugeniicola (incl. Cylindromonium gen. nov.) on leaf litter of Eugenia capensis, Cyphellophora goniomatis on leaves of Gonioma kamassi, Nothodactylaria nephrolepidis (incl. Nothodactylaria gen. nov. and Nothodactylariaceae fam. nov.) on leaves of Nephrolepis exaltata, Falcocladium eucalypti and Gyrothrix eucalypti on leaves of Eucalyptus sp., Gyrothrix oleae on leaves of Olea capensis subsp. macrocarpa, Harzia metrosideri on leaf litter of Metrosideros sp., Hippopotamyces phragmitis (incl. Hippopotamyces gen. nov.) on leaves of Phragmites australis, Lectera philenopterae on Philenoptera violacea, Leptosillia mayteni on leaves of Maytenus heterophylla, Lithohypha aloicola and Neoplatysporoides aloes on leaves of Aloe sp., Millesimomyces rhoicissi (incl. Millesimomyces gen. nov.) on leaves of Rhoicissus digitata, Neodevriesia strelitziicola on leaf litter of Strelitzia nicolai, Neokirramyces syzygii (incl. Neokirramyces gen. nov.) on leaf spots of Syzygium sp., Nothoramichloridium perseae (incl. Nothoramichloridium gen. nov. and Anungitiomycetaceae fam. nov.) on leaves of Persea americana, Paramycosphaerella watsoniae on leaf spots of Watsonia sp., Penicillium cuddlyae from dog food, Podocarpomyces knysnanus (incl. Podocarpomyces gen. nov.) on leaves of Podocarpus falcatus, Pseudocercospora heteropyxidicola on leaf spots of Heteropyxis natalensis, Pseudopenidiella podocarpi, Scolecobasidium podocarpi and Ceramothyrium podocarpicola on leaves of Podocarpus latifolius, Scolecobasidium blechni on leaves of Blechnum capense, Stomiopeltis syzygii on leaves of Syzygium chordatum, Strelitziomyces knysnanus (incl. Strelitziomyces gen. nov.) on leaves of Strelitzia alba, Talaromyces clemensii from rotting wood in goldmine, Verrucocladosporium visseri on Carpobrotus edulis. Spain, Boletopsis mediterraneensis on soil, Calycina cortegadensisi on a living twig of Castanea sativa, Emmonsiellopsis tuberculata in fluvial sediments, Mollisia cortegadensis on dead attached twig of Quercus robur, Psathyrella ovispora on soil, Pseudobeltrania lauri on leaf litter of Laurus azorica, Terfezia dunensis in soil, Tuber lucentum in soil, Venturia submersa on submerged plant debris. Thailand, Cordyceps jakajanicola on cicada nymph, Cordyceps kuiburiensis on spider, Distoseptispora caricis on leaves of Carex sp., Ophiocordyceps khonkaenensis on cicada nymph. USA, Cytosporella juncicola and Davidiellomyces juncicola on culms of Juncus effusus, Monochaetia massachusettsianum from air sample, Neohelicomyces melaleucae and Periconia neobrittanica on leaves of Melaleuca styphelioides × lanceolata, Pseudocamarosporium eucalypti on leaves of Eucalyptus sp., Pseudogymnoascus lindneri from sediment in a mine, Pseudogymnoascus turneri from sediment in a railroad tunnel, Pulchroboletus sclerotiorum on soil, Zygosporium pseudomasonii on leaf of Serenoa repens. Vietnam, Boletus candidissimus and Veloporphyrellus vulpinus on soil. Morphological and culture characteristics are supported by DNA barcodes.

Complete mitochondrial genome of Cladosporium zixishanense sp. nov. YFCC 8620 isolated from the spider in Yunnan, southwestern China

The genus Cladosporium is one of the largest and most heterogeneous genera of hyphomycetes. However, little is known about its mitogenome. Here, we first report the complete mitogenome of Cladosporium based on the Illumina sequencing data of Cladosporium zixishanense sp. nov., which was isolated from the spider. The mitogenome of C. zixishanense is composed of a circular DNA molecule with the total length of 37,197 bp, which includes 14 protein-coding genes (PCGs), 2 ribosomal RNA (rns and rnl) genes, 2 ORFs (ORF199 and ORF138), and 26 transfer RNA (tRNA) genes. The overall base composition is 34.7% A, 34.2% T(U), 15.6% C, 15.5% G, with a GC content of 31.1%. Phylogenetic analysis revealed that C. zixishanense is located in the order Capnodiales (Dothideomycetes) and forms a separate clade with strong statistical support.

Morphology and Multi-Gene Phylogeny Reveal Pestalotiopsis pinicola sp. nov. and a New Host Record of Cladosporium anthropophilum from Edible Pine (Pinus armandii) Seeds in Yunnan Province, China

This study contributes new knowledge on the diversity of conidial fungi in edible pine (Pinus armandii) seeds found in Yunnan Province, China and emphasizes the importance of edible seed products to ensure food safety standards. We isolated two fungal species, one on the pine seed coat and the other on the endosperm of the pine seed. The two fungal species were identified as Pestalotiopsis pinicola sp. nov. and a new host record Cladosporium anthropophilum. Characteristic morphological features of Pestalotiopsis pinicola were used alongside results from multi-gene phylogenetic analysis to distinguish it from currently known species within the genus. Cladosporium anthropophilum was identified as a new host record based on morphological features and phylogenetic analysis. In addition, detailed descriptions, scanned electron microscopy morphology, illustrations, and phylogenetic trees are provided to show the placement of these species.

Fungi as potential tool for polluted port sediment remediation

Contaminated sediments represent an important management problem that also concerns their remediation. Indeed, port dredging activities produce huge volumes of contaminated sediments that, in turn, require proper handling because of their quantity of inorganic and organic substances. Conventional management-remediation strategies of polluted sediment involve sediment washing, electron-chemical separation, and thermal treatment. Recently, bioremediation strategies have also been proposed as a promising answer to the problem of contaminated sediments. In this context, fungi are pioneer microorganisms known to bioconcentrate, bioaccumulate, and biostabilize heavy metals. These capabilities suggest the potential to employ indigenous fungal strains to remediate polluted port sediments. In the framework of the European Project SEDITERRA (Guidelines for the sustainable treatment of dredged sediments in the Marittimo area), the aim of this paper is to characterize the fungal communities of port sediments of Genoa and present an innovative mycoremediation protocol to evaluate the capability of indigenous fungal strains in the heavy metal remediation. In this study, Penicillium expansum Link and Paecilomyces formosus (Sakag., May. Inoue & Tada) Houbraken & Samson have been selected as fungal species for the mycoremediation treatments. The protocol requires a fungal membrane system and the results highlight efficient bioremoval of Cu and Zn from sediments.

Microbial communities of the house fly Musca domestica vary with geographical location and habitat

House flies (Musca domestica) are widespread, synanthropic filth flies commonly found on decaying matter, garbage, and feces as well as human food. They have been shown to vector microbes, including clinically relevant pathogens. Previous studies have demonstrated that house flies carry a complex and variable prokaryotic microbiota, but the main drivers underlying this variability and the influence of habitat on the microbiota remain understudied. Moreover, the differences between the external and internal microbiota and the eukaryotic components have not been examined. To obtain a comprehensive view of the fly microbiota and its environmental drivers, we sampled over 400 flies from two geographically distinct countries (Belgium and Rwanda) and three different environments-farms, homes, and hospitals. Both the internal as well as external microbiota of the house flies were studied, using amplicon sequencing targeting both bacteria and fungi. Results show that the house fly's internal bacterial community is very diverse yet relatively consistent across geographic location and habitat, dominated by genera Staphylococcus and Weissella. The external bacterial community, however, varies with geographic location and habitat. The fly fungal microbiota carries a distinct signature correlating with the country of sampling, with order Capnodiales and genus Wallemia dominating Belgian flies and genus Cladosporium dominating Rwandan fly samples. Together, our results reveal an intricate country-specific pattern for fungal communities, a relatively stable internal bacterial microbiota and a variable external bacterial microbiota that depends on geographical location and habitat. These findings suggest that vectoring of a wide spectrum of environmental microbes occurs principally through the external fly body surface, while the internal microbiome is likely more limited by fly physiology.

Different response of bacteria, archaea and fungi to process parameters in nine full-scale anaerobic digesters

Biogas production is a biotechnological process realized by complex bacterial, archaeal and likely fungal communities. Their composition was assessed in nine full-scale biogas plants with distinctly differing feedstock input and process parameters. This study investigated the actually active microbial community members by using a comprehensive sequencing approach based on ribosomal 16S and 28S rRNA fragments. The prevailing taxonomical units of each respective community were subsequently linked to process parameters. Ribosomal rRNA of bacteria, archaea and fungi, respectively, showed different compositions with respect to process parameters and supplied feedstocks: (i) bacterial communities were affected by the key factors temperature and ammonium concentration; (ii) composition of archaea was mainly related to process temperature; and (iii) relative abundance of fungi was linked to feedstocks supplied to the digesters. Anaerobic digesters with a high methane yield showed remarkably similar bacterial communities regarding identified taxonomic families. Although archaeal communities differed strongly on genus level from each other, the respective digesters still showed high methane yields. Functional redundancy of the archaeal communities may explain this effect. 28S rRNA sequences of fungi in all nine full-scale anaerobic digesters were primarily classified as facultative anaerobic Ascomycota and Basidiomycota. Since the presence of ribosomal 28S rRNA indicates that fungi may be active in the biogas digesters, further research should be carried out to examine to which extent they are important players in anaerobic digestion processes.

Molecular and morphological characterization of rice phylloplane fungi and determination of the antagonistic activity against rice pathogens

Cladosporium spp. is a cosmopolitan fungal genus. In the literature, it has been reported as a biological agent for controlling several plant diseases, but its mechanism of action has never been clarified. The present study aims to identify Cladosporium spp. based on the DNA phylogeny of nine isolates obtained from the phylloplane of rice and their potential antagonistic activity against the main fungal pathogens that affect rice crop. Nine isolates of Cladosporium spp. were identified based on DNA phylogeny, molecular and morphological characterization, and their antagonistic effects with the rice pathogens C. miyabeanus, M. oryzae, M. albescens and S. oryzae. Four isolates were selected to study lytic enzymes such as β-1,3-glucanase, chitinase and protease, and only one isolate was selected for a conidial germination and appressoria formation assay. The nine isolates were identified as C. cladosporioides, C. tenuissimum and C. subuliforme. Four isolates, identified as C. cladosporioides, inhibited the mycelial growth of rice pathogens such as C1H (68.59%) of S. oryzae, C5 G (74.32%) of C. miyabeanus, C11 G (75.97%) of M. oryzae and C24 G (77.39%) of M. albescens. C24 G showed a high activity of lytic enzymes, was tested against C. miyabeanus and M. oryzae, and inhibited conidial germination and appressorium formation by more than 59.36%. The characterization of C. cladosporioides suggested this species as a potential bioagent for the management of several rice diseases, especially rice blast. This is the first time that a potential biological agent from the genus Cladosporium identified at the species level was isolated from the rice phylloplane, and some of its mechanisms of action were demonstrated, such as increasing lytic enzyme activity against rice pathogens.

Organs, Cultivars, Soil, and Fruit Properties Affect Structure of Endophytic Mycobiota of Pinggu Peach Trees

Pinggu peach (Prunus persica (L.)) has great economic and ecological value in north China. As a plant, the peach is naturally colonized by a variety of endophytic fungi, which are very important for tree growth and health. However, the mycobiota composition and their affecting factors of the peach trees are still unknown. In our study, the fungal communities in flowers, leaves, stems, and roots of the three cultivars (Dajiubao, Qingfeng, and Jingyan) of Pinggu peach trees and in the rhizosphere soils were investigated by both Illumina Miseq sequencing of ITS rDNA and traditional culturing methods. For organs, except for roots, flowers had the highest fungal richness and diversity, while the leaves had the lowest richness and diversity. Ascomycota and Basidiomycota were the most abundant phyla among samples. The fungal assemblage composition of each organ was distinctive. Fungal communities of the three cultivars also differed from each other. The fungal community structure significantly correlated with soil pH, soil K, fruit soluble solid content, and fruit titratable acidity with the redundancy analysis (RDA). Most isolated fungal strains can be found within high-throughput sequencing identified taxa. This study indicates that plant organs, the cultivars, the soil, and fruit properties may have profound effects on the endophytic fungal community structure associated with Pinggu peach trees. With this study, microbiota-mediated pathogen protection and fruit quality promotion associated with peach trees could be further studied.

Diversity and abundance of airborne fungal spores in a rural cold dry desert environment in Argentinean Patagonia

This work describes a longitudinal study of three consecutive years carried out in the air of agricultural environments located in Northern Patagonia with cold dry desert climate (Köppen: Bwk). This study area comprises a rural valley with unique geographical and climatological conditions. Therefore, the aim of this work is to quantify and determine its fungal diversity, so this knowledge will contribute to detect potential pathogenic and toxic fungi that has been adapted to this type of environment and may overcome the incipient climate change. Samplings were conducted in two geographical zones of the study area and a microflow air sampler was used to isolate fungal taxa. The annual mean fungal counts were found in the order of E+03 CFU/m³ of air. The aerial mycoflora revealed a wide biodiversity of at least 28 genera and 50 fungal species. Cladosporium was the most abundant genus (76.97%), followed by Alternaria (12.48%), Epicoccum (4.41%) and Botrytis (1.81%). The rest of the genera were found in relative densities lower than 1%. In terms of species, C. cladosporioides (34.82%), C. limoniforme (21.72%), A. tenuissima (10.94%) and C. asperulatum predominated (9.01%). This is the first report of the air mycoflora of rural environments with cold dry desert climate which provides useful information to take preventive measures to avoid biological damage.

Emerging from the ice-fungal communities are diverse and dynamic in earliest soil developmental stages of a receding glacier

We used amplicon sequencing and isolation of fungi from in-growth mesh bags to identify active fungi in three earliest stages of soil development (SSD) at a glacier forefield (0-3, 9-14, 18-25 years after retreat of glacial ice). Soil organic matter and nutrient concentrations were extremely low, but the fungal diversity was high [220 operational taxonomic units (OTUs)/138 cultivated OTUs]. A clear successional trend was observed along SSDs, and species richness increased with time. Distinct changes in fungal community composition occurred with the advent of vascular plants. Fungal communities of recently deglaciated soil are most distinctive and rather similar to communities typical for cryoconite or ice. This indicates melting water as an important inoculum for native soil. Moreover, distinct seasonal differences were detected in fungal communities. Some fungal taxa, especially of the class Microbotryomycetes, showed a clear preference for winter and early SSD. Our results provide insight into new facets regarding the ecology of fungal taxa, for example, by showing that many fungal taxa might have an alternative, saprobial lifestyle in snow-covered, as supposed for a few biotrophic plant pathogens of class Pucciniomycetes. The isolated fungi include a high proportion of unknown species, which can be formally described and used for experimental approaches.

Wastewater-Agar as a selection environment: A first step towards a fungal in-situ bioaugmentation strategy

Viable and metabolically active fungi in toxic mixed liquors, treating landfill leachates and municipal wastewaters, were identified by culture depending methods. A selective culture medium consisting of wastewater and agar (WA) restrained fungi that could be randomly present (94% of the 51 taxa retrieved on WA were sample-specific), overcoming the problem of fast growing fungi or mycoparasite fungi. Moreover, WA allowed the isolation of fungi with a possible role in the degradation of pollutants typically present in the two wastewaters. Phoma medicaginis var. medicaginis, Chaetomium globosum, and Geotrichum candidum were mainly found in municipal wastewater, whereas Pseudallescheria boydii, Scedosporium apiospermum, Aspergillus pseudodeflectus, and Scopulariopsis brevicaulis were typical of landfill leachate.

Disseminated melanized fungal infection due to Cladosporium halotolerans in a dog coinfected with canine adenovirus-1 and canine parvovirus-2

This report presents the pathologic findings associated with disseminated infection due to Cladosporium halotolerans in a dog that was simultaneously infected with canine adenovirus-1 (CAdV-1) and canine parvovirus-2 (CPV-2). A 12-year-old, mixed breed dog, with a clinical history of neurological manifestations was submitted for routine autopsy due to poor prognosis. The principal pathologic findings were mycotic necrotizing nephritis, hepatitis, and splenitis with embolic dissemination to the brain resulting in mycotic necrotizing meningoencephalitis, ventriculitis, choroid plexitis, and obstructive hydrocephalus associated with intralesional and intravascular septate pigmented fungi. PCR and sequencing of the ITS region of fungi revealed that the intralesional fungal organisms had 82% nucleotide identity with members of the Cladosporium sphaerospermum complex of organisms. However, a PCR assay and sequencing of the beta tubulin gene confirmed that the organism identified in this dog had 100% nucleotide sequence identity with C. halotolerans. Using immunohistochemistry, intralesional antigens of CAdV-1 were identified within the epithelial cells of the liver and lungs; there was positive immunolabeling for CPV-2 antigens in degenerated cardiomyocytes. These findings confirmed the active participation of C. halotolerans in the development of disseminated cladosporiosis in this dog and represent a rare occurrence of concomitant infection with CAdV-1 and CPV-2.

New R-Based Methodology to Optimize the Identification of Root Endophytes against Heterobasidion parviporum

Many root fungal endophytes inhabiting forest trees have potential impact on the health and disease progression of certain tree species. Hence, the screening of root endophytes for their biocontrol abilities is relevant for their potential to protect their hosts against invaders. The aim of this research is to screen for the potential inhibitory effects of selected conifer root endophytes during interaction, in vitro, with the root rot pathogen, Heterobasidion parviporum. Here, we introduce a guideline that facilitates the use of root fungal endophytes as biocontrol agents. We isolated fungal root endophytes from eight different conifers. These root fungal endophytes were evaluated for their antagonism against the root rot pathogen, H. parviporum, by means of paired-culture antagonism assays. We determined the antagonism of the isolated root fungal endophytes to elucidate potential biocontrol applications. For the analysis, a software package in R was developed. Endophyte candidates with antagonistic potential were identified.

Biodiversity and antifouling activity of fungi associated with two soft corals from the South China Sea

Bacteria in corals have been studied in detail in the past decades. However, the biodiversity and bioactivity of fungi in corals are still poorly understood. This study investigated the biodiversity and antifouling activity of fungi in soft corals Cladiella krempfi and Sarcophyton tortuosum from the South China Sea. A high diverse and abundant fungal community was found in the two soft corals. Furthermore, five isolates shared 83-95% similarity with their closest relatives, indicating that they might be novel species in genera Phaeoshaeria and Mucor. In addition, approximately 50% of the representative isolates exhibited distinct antifouling activity. In particular, isolates Fungal sp. SCAU132 and Fungal sp. SCAU133 displayed very strong antifouling activity against Bugula neritina, suggesting they can provide a potential resource for further investigation on isolation of novel antifouling metabolites. To our knowledge, this study is the first report to investigate the biodiversity and antifouling activity of fungi in C. krempfi and S. tortuosum.

Fungal communities in oil contaminated mangrove sediments - Who is in the mud?

Mangroves are ecosystems located in tropical and subtropical regions of the world and are vital for coastal protection. Their unique characteristics make them hotspots for carbon cycling and biological diversity. Studies on isolated filamentous fungi and environmental and anthropogenic factors that influence sediments offer new understandings on how to preserve mangroves. Here we report on the filamentous fungi isolated from four mangroves. We correlated fungal community composition with sediment texture, polycyclic aromatic hydrocarbons concentration (oil pollution), pH, salinity, organic matter, total and thermotolerant coliforms (sewage pollution). In total we identified 34 genera and 97 species. The most polluted sites had highest species richness whereas the best preserved site showed the lowest species richness. Oil spill and sewage pollution were identified as the drivers of fungal community composition in the most polluted sites. We found very distinct fungal communities with no >5 species shared between any two mangrove sites.

Micromycetes as colonizers of mineral building materials in historic monuments and museums

Complex of microfungi colonizing mineral building materials, i.e. limestone and plaster, in interiors of cultural heritage was characterized. Wide-scale investigation was carried out with fourteen objects studied. We have revealed a specific culturable community. We have analyzed role of obtained microfungi in biodeterioraton process on the basis of our tests (pH and water activity preferences, ability to solubilize CaCO₃) and literature data (substrate preferences and enzyme activities). The species most actively developing in mineral materials in indoor environments were Acremonium charticola, Acremonium furcatum, Lecanicillium sp., Parengyodontium album, Purpureocillium lilacinum and Sarocladium kiliense. Considering this fact and their ability to develop successfully at extremely wide range of pH values from slightly acidic to alkaline ones and their high enzymatic activities we conclude that the listed species are of high interest in seeking the cause of biodeterioration. These species can actively develop in materials penetrating for years deep into the substrates and causing their deterioration in conditions of considerably heightened moisture content. In this group, A. charticola and Lecanicillium sp. were able to solubilize CaCO₃.