Spores Research Articles

Bacteria Associated with Spores of Arbuscular Mycorrhizal Fungi Improve the Effectiveness of Fungal Inocula for Red Raspberry Biotization

Intensive crop production leads to the disruption of the symbiosis between plants and their associated microorganisms, resulting in suboptimal plant productivity and lower yield quality. Therefore, it is necessary to improve existing methods and explore modern, environmentally friendly approaches to crop production. One of these methods is biotization, which involves the inoculation of plants with appropriately selected symbiotic microorganisms which play a beneficial role in plant adaptation to the environment. In this study, we tested the possibility of using a multi-microorganismal inoculum composed of arbuscular mycorrhizal fungi (AMF) and AMF spore-associated bacteria for biotization of the red raspberry. Bacteria were isolated from the spores of AMF, and their plant growth-promoting properties were tested. AMF inocula were supplemented with selected bacterial strains to investigate their effect on the growth and vitality of the raspberry. The investigations were carried out in the laboratory and on a semi-industrial scale in a polytunnel where commercial production of seedlings is carried out. In the semi-industrial experiment, we tested the growth parameters of plants and physiological response of the plant to temporary water shortage. We isolated over fifty strains of bacteria associated with spores of AMF. Only part of them showed plant growth-promoting properties, and six of these (belonging to the Paenibacillus genus) were used for the inoculum. AMF inoculation and co-inoculation of AMF and bacteria isolated from AMF spores improved plant growth and vitality in both experimental setups. Plant dry weight was improved by 70%, and selected chlorophyll fluorescence parameters (the contribution of light to primary photochemistry and fraction of reaction centre chlorophyll per chlorophyll of the antennae) were increased. The inoculum improved carbon assimilation, photosynthetic rate, stomatal conductance and transpiration after temporary water shortage. Raspberry biotization with AMF and bacteria associated with spores has potential applications in horticulture where ecological methods based on plant microorganism interaction are in demand.

Organic tracers in fine and coarse aerosols at an urban Mediterranean site: contribution of biomass burning and biogenic emissions.

The concentrations of anhydrosugars (levoglucosan, mannosan, and galactosan), polyols (inositol, xylitol, sorbitol, and mannitol), and glucose were measured in PM1 and PM10 samples collected during 1 year at a traffic site in the city of Elche (southeastern Spain). Levoglucosan, mannosan, and galactosan were mainly found in the PM1 fraction since they are mainly emitted from biomass burning (BB). Likewise, inositol, xylitol, and sorbitol were primarily distributed in the fine mode, suggesting a non-negligible contribution from anthropogenic sources (specifically BB) to the levels of these compounds. This was supported by their seasonal variations, with higher concentrations during winter, and their correlations with levoglucosan concentrations. The average contributions of biomass burning and biogenic sources to OC and PM levels were calculated using levoglucosan and mannitol, respectively, as tracers. On average, BB accounted for 12% and 16% of the OC in PM1 and PM10, while the estimated contribution of fungal spores to OC and PM10 levels was 1.2 and 0.8%, respectively. The results of the present study suggest that, at least in the study area, most sugar alcohols are not appropriate tracers of biogenic emissions.

Biocompatibility of Brazilian native yeast-derived sophorolipids and Trichoderma harzianum as plant-growth promoting bioformulations

The replacement of agrochemicals by biomolecules is imperative to mitigate soil contamination and inactivation of its core microbiota. Within this context, this study aimed at the interaction between a biological control agent such as Trichoderma harzianum CCT 2160 (BF-Th) and the biosurfactants (BSs) derived from the native Brazilian yeast Starmerella bombicola UFMG-CM-Y6419. Thereafter, their potential in germination of Oryza sativa L. seeds was tested. Both bioproducts were produced on site and characterized according to their chemical composition by HPLC-MS and GC-MS for BSs and SDS-PAGE gel for BF-Th. The BSs were confirmed to be sophorolipids (SLs) which is a well-studied compound with antimicrobial activity. The biocompatibility was examined by cultivating the fungus with SLs supplementation ranging from 0.1 to 2 g/L in solid and submerged fermentation. In solid state fermentation the supplementation of SLs enhanced spore production, conferring the synergy of both bioproducts. For the germination assays, bioformulations composed of SLs, BF-Th and combined (SLT) were applied in the germination of O. sativa L seeds achieving an improvement of up to 30% in morphological aspects such as root and shoot size as well as the presence of lateral roots. It was hypothesized that SLs were able to regulate phytohormones expression such as auxins and gibberellins during early stage of growth, pointing to their novel plant-growth stimulating properties. Thus, this study has pointed to the potential of hybrid bioformulations composed of biosurfactants and active endophytic fungal spores in order to augment the plant fitness and possibly the control of diseases.

Prosthetic Rehabilitation of Post Covid Mucormycosis of Maxilla with Definitive Obturator Prosthesis- A 24 Month Follow Up Case Report

The second wave of COVID-19 in April 2021 witnessed a new mutated variant of SARS-CoV2 known as B.1.617 resulting in Mucormycosis. Inhalation, ingestion, or contamination of ulcerated mucosa by fungal spores results in infection and cause Mucormycosis. Objective: To highlight how a complex case of oral mucormycosis can be misdiagnosed due to its similar clinical presentations with other periodontal diseases and benefits of prosthetic rehabilitation of surgical defects with definitive obturator which improves the quality of life by restoring oral function and aesthetics. Case report: A 35-year-old female reported with chief complaint of pain, pus and mobility in upper front teeth region of 2 months and swelling of mid-face. Darkening of skin, swelling with tenderness over bilateral malar- infraorbital regions with epiphora and blurred vision in right eye and discharge from right nostril. She had multiple abscess in attached gingiva in incisor and premolar region of maxilla having probing depths ≤ 4mm with mobility. Conclusion: A precise diagnosis is prerequisite to specific treatment of any disease. Treatment often requires an extensive surgical resection causing facial deformation, masticatory, swallowing and speech problems. It is important to rehabilitate these patients by correcting the defects with the help of obturators and improve their lifestyle.

Potential of gaseous ozone to inhibit Aspergillus flavus and detoxify aflatoxin B1 in agar and broth media (solid and liquid food states) at different growth phases

Agricultural food crops are prone to Aspergillus flavus contamination during post-harvest and storage stages. Their consumption is toxic due to aflatoxin production, a potent carcinogenic and immunosuppressive agent. Present study explored the ozone's effect as a function of food media states (solid and liquid) to inhibit Aspergillus flavus under three modes of treatment (0th-day, Every-day and Nth-day ozone treatment), that adds novelty to the work. Results showed that ozone concentration to treat Aspergillus flavus and aflatoxins is higher in liquid than solid food state. Further, ozone treatment affected the intactness of fungal spores and inhibited 100% conidial growth. It also exhibited 88 %% inhibition and 90% reduced biomass in solid and liquid food states. Effectiveness of ozone towards inhibiting Aspergillus flavus and aflatoxin was in the following order: Nth -day treatment > Every-day treatment > 0th -day ozone treatment. Further, growth studies showed ozone treated cultures exhibit delayed sporulation and aflatoxin production by 72 h. when cultured on fresh media. Additionally, ozone purging into extracted aflatoxin led to > 99% degradation. The above results show the significance of ozone technology in increasing the shelf-life of post-harvested food crops. Further, it can be used as a disinfectant in the food industry to treat contaminated food crops/liquid products by detoxifying aflatoxins.

Nematophagous fungi species from Erzurum and Erzincan provinces in Türkiye

In Erzurum and Erzincan provinces, some nematophagous fungi were determined on roots of alfalfa (Medicago sativa L.), potato (Solanum tuberosum L.) and strawberry (Fragaria x ananassa Duchesne) plants during 2009-2011, and identification of fungi species was performed by classical and/or molecular techniques. Purified 5 isolates were determined as Arthrobotrys cladodes Drechsler 1937 (1 isolate), Arthrobotrys conoides Drechsler 1937 (1 isolate) and Arthrobotrys superba Corda 1839 (3 isolates). Identification of Arthrobotrys isolates was also confirmed by ribosomal DNA (rDNA)-ITS (internal transcribed spacer) sequence analysis. Harposporium genus was also determined considering the morphological characteristic of fungal spores growing on nematodes found in two samples, but these fungi could not be purified. Harposporium species were identified as Harposporium anguillulae Lohde emend. Zopf 1888 and Harposporium crassum A.M. Sheph 1955 according to the morphological characteristic. According to our knowledge, all Arthrobotrys and Harposporium species identified in this study were reported for first time in Türkiye.

Role of reactive oxygen species (ROS) signaling pathway in the wound-induced spore formation of Pyropia yezoensis

Asexual spore formation of Pyropia yezoensis significantly impacts yield. After mechanical sectioning of leafy thalli into fragments, somatic cells rapidly develop into a large number of wound-induced spores (WIS, a form of asexual spores). Recent studies on P. yezoensis have demonstrated a notable increase in reactive oxygen species (ROS) during this process; however, the regulatory mechanism underlying this ROS signaling remains largely unclear. This paper shows that in P. yezoensis, ROS signals play a crucial role in WIS formation. When treated with the ROS-producing enzyme NADPH oxidase inhibitor diphenyleneiodonium chloride, P. yezoensis thalli fragments strongly repressed WIS formation, accompanied by a significant decrease of ROS levels, malondialdehyde contents, and activities of NADPH oxidase and antioxidant enzymes. The expression levels of respiratory burst oxidase homolog genes, aquaporin protein genes, superoxide dismutase genes, glutathione S-transferase genes, and glutathioneperoxidase genes were also decreased, thus inhibiting WIS formation. As an upstream signal, ROS promote ion exchange and metabolism both inside and outside of cells within the first 12 h of wound stress. Following 12 h of wound stress, transcriptional activation of specific genes associated with cell cycle progression—which promotes cell division and dedifferentiation under normal conditions—was also blocked by diphenyleneiodonium chloride. In addition, the generated ROS signals also regulated the expression of mitogen-activated protein kinase family genes under wound stress. Overall, this study provides novel insights into the molecular mechanism underlying the ROS signaling regulation of WIS formation in P. yezoensis.

Diversity and Distribution Patterns of Culturable Airborne Fungi in Jiroft City

Background and Aims: Fungal spores constitute a significant portion of primary biological aerosol particles, and large amounts have been identified in the air. They are present in the atmosphere throughout the year, and their concentration varies due to meteorological factors such as temperature, relative humidity, location, construction conditions, and vegetation. Exposure to airborne fungi has been linked with diseases such as allergic respiratory symptoms, rhinitis, asthma, and various infections. This study investigates the diversity and distribution of airborne fungal spores in Jiroft City, located in the southern region of Iran. Materials and Methods: Airborne fungal composition was sampled from indoor, outdoor, and hospital air using the sedimentation plate method. Grown fungi were identified using standard mycological techniques, including determining macroscopic and microscopic characteristics. Results: A total of 230 colonies belonging to 11 genera of fungi were isolated from all culture media. Fungi were isolated from 53 (80.3%) samples. The highest and lowest percent of positive samples were found in outdoor (100%) and hospital (64.3%) air samples, respectively. Cladosporium (43.9%) and Aspergillus (36.4%) were the most common fungi isolated from the samples. Rhodotorula, Syncephalastrum, Paecilomyces, Mucor, and Acremonium were the least isolated fungi (1.5%). Conclusion: This study showed the difference in the diversity and distribution of fungi in different environments. Cladosporium and Aspergillus were the most common fungi isolated, which need to be considered due to their ability to cause various diseases.

The synergistic effects of a leaf mixture on decomposition change with a period of terrestrial exposure prior to immersion in a stream.

The effect of mixing litter on decomposition has received considerable attention in terrestrial and aquatic (but rarely in both) ecosystems, with a striking lack of consensus in the obtained results. We studied the decomposition of a mixture of poplar and alder in three terrestrial: aquatic exposures to determine (1) if the effect of mixing litter on mass loss, associated decomposers (fungal biomass, sporulation rates, and richness), and detritivores (abundance, biomass, and richness of invertebrate shredders) differs between the stream (fully aquatic exposure) and when litter is exposed to a period of terrestrial exposure prior to immersion and (2) the effect of the mixture across exposure scenarios. The effect of the mixture was additive on mass loss and synergistic on decomposers and detritivores across exposure scenarios. Within scenarios, mass loss and decomposers showed synergistic effects only in the fully aquatic exposure, detritivores showed synergistic effects only when the period of terrestrial was shorter than the period of aquatic exposure, and when the period of terrestrial was equal to the period of aquatic exposure the effect of the mixture was additive on mass loss, decomposers, and detritivores. The species-specific effects also differed among exposure scenarios. Alder affected poplar only when there was a period of terrestrial exposure, with increased sporulation rates and fungal richness in exposure 25:75, and increased mass loss in exposure 50:50. Poplar affected alder only under fully aquatic exposure, with increased mass loss. In conclusion, the synergistic effects of the mixture changed with a period of terrestrial exposure prior to immersion. These results provide a cross-boundary perspective on the effect of mixing litter, showing a legacy effect of exposure to terrestrial decomposition on the fate of plant litter in aquatic ecosystems and highlighting the importance of also assessing the effect of mixing litter on the associated biota and not only on mass loss.

The role of automatic pollen and fungal spore monitoring across major end-user domains

The advent of automatic pollen and fungal spore monitoring over the past few years has brought about a paradigm change. The provision of real-time information at high temporal resolution opens the door to a wide range of improvements in terms of the products and services made available to a widening range of end-users and stakeholders. As technology and methods mature, it is essential to properly quantify the impact automatic monitoring has on the different end-user domains to better understand the real long-term benefits to society. In this paper, we focus the main domains where such impacts are expected, using Europe as a basis to provide qualitative estimates and to describe research needs to better quantify impacts in future. This will, in part, also serve to justify further investment and help to expand monitoring networks.

A new spatial model for tracking plant spore dispersal and disease spread

Plant diseases caused by spores can cause severe damage to crop production, resulting in yield losses of up to 75%. Spores can be carried over long distances by wind, water, insects, and humans, meaning that even one infected agricultural field can spread the disease to neighboring fields. Although mathematical models exist to describe the spread of plant diseases, they often do not take into account the transport and location of spores, which limits the ability to make spatial forecasts. To address this limitation, we developed a spatial model based on Healthy sites H, Latent sites L, Infected sites I, Removed sites R, and spore sites X (HLIRX), which describes the spore movement between fields, allowing us to simulate the spatial invasion of plant diseases. We analyzed the existence and stability of steady states in the model using the finite difference method. Our findings reveal that the disease-free equilibrium is unstable, while the boundary and endemic equilibria are asymptotically stable, depending on the spore dispersion term. Moreover, we observed that the dynamics of the population in each field exhibit a consistent pattern, with leftward or rightward shifts depending on the distance from the source of infection, which cannot be captured from the temporal model. We also investigated the impact of two spatial parameters, the dispersal kernel parameter and spore migration rate, and found that both parameters lead to an increase in the number of infected plants but have no significant effect on disease severity. In addition, we discovered that the time until the infected population peaks is linearly related to the distance between each field and the source of infection, with a Pearson correlation coefficient greater than 0.99 (p < 0.001). Our developed model provides a useful tool for studying the spatial dispersion of plant diseases distributed by spores, as it considers the transport and location of spores and can be used to make spatial forecasts.

Antifungal evaluation of turmeric rhizome extract against Colletotrichum capsici, the causal agent of anthracnose on red-chili peppers (Capsicum annum L.)

This study was conducted to evaluate the antifungal activity of the ethanolic extract of turmeric rhizome against Colletotrichum capsici Syd. and its efficacy in reducing anthracnose disease development on red chili peppers. The in vitro experiment aimed to determine the effect of the extract on inhibiting C. capsici growth in potato sucrose agar (PSA) medium incorporating the turmeric rhizome extract. The variables examined were mycelial growth, fungal sporulation, and spore germination. The in vivo experiment aimed to evaluate the effectiveness of the extract in reducing disease development on red chili peppers. The treatments were conducted using a completely randomized design with five concentration treatments and three replicates. The variables examined were radial mycelial growth zone diameter, fungal sporulation, spore germination, and disease intensity. Data were analyzed by analysis of variance, and the least significant difference was used for comparing means between treatments. The results of these experiments showed that ethanolic turmeric rhizome extract exhibited antifungal activity against C. capsici both in vitro and in vivo conditions. Turmeric rhizome extracts with concentrations of 1%, 2%, 3%, and 4% significantly inhibited mycelial growth, and even at a 4% concentration, C. capsici fungal colonies did not grow. Evaluation of the effect of the extract on fungal sporulation showed that inhibition occurred at a concentration of 3%, while inhibition of spore germination occurred at concentrations of 1%, 2%, and 3%. Application of turmeric extract at concentrations of 1%, 2%, 3%, and 4% effectively reduced the intensity of anthracnose on red chili.

Further observations on stalked microfossils from the Lower Devonian Rhynie cherts that resemble the algae Characiopsis (Eustigmatophyceae) and Characium (Chlorophyceae)

The Lower Devonian Rhynie cherts yield abundant fossils of many different microorganisms. One of them is an oblong cell (up to 15 μm long) on a slender stipe; a basal attachment disc or cushion is visible in some specimens. This fossil was originally described (but not named) based on specimens associated with fungal spores in an aquatic environment, and its striking resemblance to present-day epibiotic freshwater algae of the genera Characiopsis (Eustigmatophyceae) and Characium (Chlorophyceae) was noted. However, none of the original specimens had been preserved attached to a substrate. Here, I revisit the fossil using new, better-preserved specimens from the same setting, most of which are attached to land plant cuticles. Although the affinities of the fossil remain unresolved, the new material reinforces its status as a discrete aquatic life form, most likely belonging to the algae. A new fossil-genus, Characrhynium gen. nov., and species, C. amoenum sp. nov., are therefore formally proposed for it. Characrhynium amoenum is evidence that submerged surfaces in the Rhynie ecosystem could be overgrown with epibiotic autotrophs.

Fungal Spore Richness and Abundance of Allergenic Taxa: Comparing a Portable Impactor and Passive Trap Indoors and Outdoors in an Urban Setting

Fungal spores are common airborne allergens, and fungal richness has been implicated in allergic disease. Amplicon sequencing of environmental DNA from air samples is a promising method to estimate fungal spore richness with semi-quantification of hundreds of taxa and can be combined with quantitative PCR to derive abundance estimates. However, it remains unclear how the choice of air sampling method influences these estimates. This study compared active sampling with a portable impactor and passive sampling with a passive trap over different durations to estimate fungal spore richness and the abundance of allergenic taxa. Air sampling was conducted indoors and outdoors at 12 residences, including repeated measurements with a portable impactor and passive traps with 1-day and 7-day durations. ITS2 amplicon sequence data were transformed to spore equivalents estimated by quantitative PCR, repeated active samples were combined, and abundance-based rarefaction was performed to standardize sample coverage for estimation of genus-level richness and spore abundance. Rarefied fungal richness was similar between methods indoors but higher for passive traps with a 7-day duration outdoors. Rarefied abundance of allergenic genera was similar between methods but some genera had lower abundance for passive traps with a 1-day duration, which differed indoors and outdoors indicating stochasticity in the collection of spores on collocated samplers. This study found that similar estimates of fungal spore richness and abundance of allergenic taxa can be obtained using a portable impactor or a passive trap within one day and that increased passive sample duration provides limited additional information.

Overview of Health and Safety Risks in the Process of Production and Storage of Forest Biomass for Energy Purposes—A Review

With increasing demands on the quality and quantity of produced biomass, as the main element of the knowledge-based economy, people and the issue of safety and health protection at work are coming to the fore. The aim of the work is the synthesis and overview of the results of the analysis of the health and safety risks of the production of forest biomass in various production phases, starting with its cultivation, through the harvesting production and transport process, up to the issue of its safe storage until it is used for the production of primary energy. Based on the analyzed overview of the existing risks in the production and storage of biomass, it can be concluded that the largest number of works is dedicated to the technological process of storage and consumption of the produced forms of biomass. Of the risks in this phase, the largest number of works is devoted to the risks of the production of spores of phytopathogens and fungi threatening human health. Further research should be primarily oriented toward creating models and modeling the processes of the emergence of these risk factors and the dynamics of their growth.

Active Packaging Systems to Extend the Shelf Life of ‘Italia’ Table Grapes

Sulfur dioxide (SO2)-generating pads associated with perforated plastic liners are often used to control gray mold in table grapes during cold storage; however, SO2 may cause bleaching, shattered berries, and an unwanted taste. To overcome this difficulty, a field ultrafast SO2-generating pad was designed to be used for a few hours before packaging grape bunches as an alternative for eradicating spores of fungi from berry skin. This study aimed to assess the postharvest conservation and shelf life of ‘Italia’ table grapes packaged in plastic clamshells and perforated plastic liners using the field ultra-fast SO2-generating pads before packaging, associated with or without slow- or dual-phase SO2-generating pads during cold storage. The packaged grapes were cold stored (1.0 ± 1.0 °C; 95% relative humidity), and after 45 d, grapes were placed at room temperature (22.0 ± 1.0 °C) without plastic liners and SO2-generating pads for 3 d. Before and after the grapes had been subjected to the field ultra-fast SO2-generating pads, the quantification of filamentous fungi on the surface of the berries was assessed. The use of field ultra-fast SO2-generating pads before packaging, associated with slow- or dual-phase SO2-generating pads during cold storage, resulted in a lower incidence of gray mold after 45 d of storage, with low weight loss and shattered berries, good preservation of stem freshness, and no impairment in the color and firmness of the berries. Additionally, a significant decrease in disease incidence was observed when using only the dual-phase SO2-generating pads in cold storage, with good maintenance of bunch quality.

A Bacillus velezensis strain shows antimicrobial activity against soilborne and foliar fungi and oomycetes.

Biological control uses naturally occurring antagonists such as bacteria or fungi for environmentally friendly control of plant pathogens. Bacillus spp. have been used for biocontrol of numerous plant and insect pests and are well-known to synthesize a variety of bioactive secondary metabolites. We hypothesized that bacteria isolated from agricultural soil would be effective antagonists of soilborne fungal pathogens. Here, we show that the Delaware soil isolate Bacillus velezensis strain S4 has in vitro activity against soilborne and foliar plant pathogenic fungi, including two with a large host range, and one oomycete. Further, this strain shows putative protease and cellulase activity, consistent with our prior finding that the genome of this organism is highly enriched in antifungal and antimicrobial biosynthetic gene clusters. We demonstrate that this bacterium causes changes to the fungal and oomycete hyphae at the inhibition zone, with some of the hyphae forming bubble-like structures and irregular branching. We tested strain S4 against Magnaporthe oryzae spores, which typically form germ tubes and penetration structures called appressoria, on the surface of the leaf. Our results suggest that after 12 hours of incubation with the bacterium, fungal spores form germ tubes, but instead of producing appressoria, they appear to form rounded, bubble-like structures. Future work will investigate whether a single antifungal molecule induces all these effects, or if they are the result of a combination of bacterially produced antimicrobials.

Application of Environmental and Biological Frequency Indicators to Assess the Serpula lacrymans Fungus in Wooden Dwellings

High moisture content, low ventilation levels, and changes in the hygrothermal design of wooden dwellings could generate environmental conditions favorable for developing the rot fungus Serpula lacrymans, which is known as the most destructive fungus of its kind. The purpose of this research was to develop an experimental methodology to determine the conditions of the appearance of the fungus S. lacrymans, through in situ measurement of biological and environmental frequency indicators for wooden dwellings in South Central Chile. The referential standards for the appearance of the fungus were determined based on specialized literature and measurements of dwellings with and without deterioration. The frequency indicators for the appearance of the fungus defined and studied were as follows: frequency of air temperature FATs (%), frequency of relative humidity FRMs (%), frequency of ventilation rate FVRs (%), and rot fungus spore concentrations (CFU/pp). The methodology was validated by being measured in various enclosures and spaces under the floor in wooden dwellings in the cities of Valdivia and Temuco. The results confirmed the strong relationship between environmental relative humidity frequencies, ventilation levels, and spore concentration regarding the appearance of the fungus, where the growth dynamics cannot be separately explained without a previous analysis of the variables. In general, the dwellings most affected by the presence of the fungus had the greatest moisture levels, lower ventilation levels, and greater spore concentration. This study is the basis to diagnose the phenomena of the appearance of the rot fungus in wooden dwellings in climates favorable for its development.

Mid-Miocene onset of the NE Bohemian Massif (SW Poland, Europe) growth, landscape evolution, and paleoenvironmental changes unraveled using paleokarst sediment palynology

Newly discovered paleokarst sediments with an abundant Miocene palynological record in the Eastern Sudetes bridge the gap in reconstructing the landscape and tectonic history of the NE Bohemian Massif during the Neogene. Palynological analysis performed for seven samples derived from the karst fissure allowed the examination of the sporomorph distribution (pollen grains and spores of plants) and nonpollen palynomorph content (algal and fungal microremains) in each layer. The results revealed the presence of numerous pre-Quaternary taxa, including “paleotropical” species, within the analyzed sediments. The pollen analysis results indicate a warm-temperate and humid climate during sedimentation of the Nowy Waliszów karst infill, along with the development of wetland vegetation (swamp forests, riparian forests, and shrub bogs) and mesophytic forests. Recorded taxa are typical for flat and hilly landscapes, predating growth of the present >1000-m relief mountainous topography and formation of the primary European triple drainage divide in the Śnieżnik Massif area. Paleokarst palynology strongly supports a mid-Miocene (∼15 ± 1.5 Ma) onset of environmental change in the Sudetes due to accelerated tectonic uplift of the Eastern Boundary Fault bounding the Upper Nysa Kłodzka Graben and Orlica–Śnieżnik Dome tectonic block. The data presented enhance our understanding of the pre-Pleistocene development of the NE Bohemian Massif, with a particular focus on the orogen-scale landscape evolution from flat, inland wetlands to hilly, mountainous topography.

Ecological competition in the oral mycobiome of Hispanic adults living in Puerto Rico associates with periodontitis

Background: Fungi are a major component of the human microbiome that only recently received attention. The imbalance of indigenous fungal communities and environmental fungi present in the oral cavity may have a role in oral dysbiosis, which could exacerbate oral inflammatory diseases. Methods: We performed a cross-sectional study and recruited 88 participants aged 21 to 49 from sexually transmitted infection clinics in Puerto Rico. A full-mouth periodontal examination following the NHANES protocol defined periodontal severity (CDC/AAP). ITS2 (fungal) genes were amplified and sequenced for mycobiota characterization of yeast and environmental fungi. Environmental outdoor spore levels were measured daily by the American Academy of Allergy Asthma and Immunology San Juan station and defined by quartiles as spore scores. Results: Our data indicate polymicrobial colonization of yeast and environmental fungi in the oral cavity. Dominant taxa associated with periodontal disease included Saccharomyces cerevisiae, Rigidoporus vinctus, and Aspergillus penicilloides, while Candida albicans were found to be ubiquitous. Fungal aerosols were found to impact the oral cavity biofilm, likely due to competition and neutralization by inhaled outdoor and indoor fungal spores. Conclusion: To our knowledge, this is the first report showcasing the ecological competition of measured outdoor environmental fungi with the human oral mycobiota.