Fungi in a changing world: growth rates will be elevated, but spore production may decrease in future climates

Ganoderma basidiospores in the air in relation to land cover and weather patterns in a temperate climate zone

Aeromycological monitoring of Ganoderma spores allows us to determine seasonal and daily fluctuations in the concentration of spores in the air and to determine periods of high concentration during which allergy and asthma symptoms may appear in allergic people. Fluctuations in basidiospore concentrations depend on climatic and weather factors and types of land use. The aim of the work was a spatiotemporal analysis of the concentration of Ganoderma spores in the air of a city and a village in a transitional temperate climate. Particular attention was paid to the types of land development, in which monitoring was carried out using Hirst volumetric traps. Furthermore, monitoring was carried out at various heights. Studies have shown that on a small spatial scale, the dynamics of the seasons of Ganoderma spore occurrence in the air are similar. However, the intensity of seasons, determined by the total sum of spores, is lower in the city than in the countryside. Differences in concentrations were found between sites located at different heights - the higher it is, the lower the concentrations are and the longer delay in the hours of maximum concentrations. The research confirms the hypothesis that land development, weather factors, and the altitude at which monitoring is carried out influence the aerobiology of Ganoderma spores.

Climate Change and Allergens: Current and Future Impacts

Climate change will continue to impact allergic diseases in direct and indirect ways. Rising global temperatures are contributing to increased duration of pollen seasons, altered aeroallergen production and potency of allergens, and changes in the geographic distribution of allergenic plants that drive increased human exposure to aeroallergens and increased allergic disease morbidity. Climate change is inextricably linked with air pollution, the latter of which was shown to act as an adjuvant for allergic inflammatory processes promoting allergic sensitization. Pollutant exposure is also linked with higher prevalence of childhood asthma and exacerbation of existing asthma and allergic disease. Increased exposure, or co-exposure, to aeroallergens and air pollution as a result of climate change will result in higher rates of sensitization, and incident allergic disease remains uncertain. Vulnerable populations, including children, the elderly, and marginalized groups, are likely to be disproportionately affected. This review summarizes the current knowledge of the effects of climate change on aeroallergens, and by extension, allergic disease. Addressing these health challenges requires a comprehensive understanding of the interaction between climate change, allergens, pollution and public health, alongside proactive measures to mitigate these effects.

The Effect of Climate Change on Allergen and Irritant Exposure

As the effects of anthropogenic climate change have become more apparent, the influences of climate and extreme weather events on health have continued to gain attention. The fact Earth has warmed over the past century is indisputable and the rate of warming is more alarming. As a result of anthropogenic climate change, an alteration in the air mixture has occurred over time. These changes have increased human exposures to respiratory irritants such as ground-level ozone, volatile organic compounds, nitrogen dioxide, sulfur dioxide, carbon monoxide, and polycyclic aromatic hydrocarbons. A significant amount of research has investigated the effects of climate change on aeroallergens, which has shown that elevated temperatures and increased carbon dioxide levels have produced prolonged and more robust pollen seasons for most taxa studied. In addition, it appears possible that exposure of some plants to air pollution may result in more allergenic pollen. Increased human exposures to these respiratory irritants and aeroallergens appears to disproportionality effect vulnerable populations throughout the world. It is essential to understand that climate change is more than an environmental inconvenience and realize the effects to human health are directly related and conceivably immeasurable. It is vital to conduct additional research related to climate change and health that is collaborative, multisectoral, and transdisciplinary. There should be a focus on risk reduction, mitigation, and preparedness for climate change and extreme weather events for all populations around the globe.

Alternaria Species on Convolvulus arvensis Revealed as a Potential Inoculum Source for Solanaceous Crops in Serbia

Alternaria pathogens are a global agronomic challenge affecting the health of Solanaceae crops. Crop debris, seeds, and perennial weeds are potential inoculum reservoirs, but knowledge on their relative importance remains limited. Plants of Convolvulus arvensis showing early blight and brown leaf spot symptoms were collected from in and around potato and tomato fields in Serbia, grown both in open conditions and in tunnels, in the late season of 2021 to 2022. Morphological characterization and multilocus sequence analysis were performed on collected samples, using three genes (GPD, CAL, and RPB2) for large-spored species and six genes (Alt a1, ATP, HIS3, endoPG, TEF-1, and OPA10-2) for small-spored species of Alternaria. A total of 58 strains were identified: four large-spored species (A. grandis, A. solani, A. protenta, and A. linariae) and two small-spored species (A. alternata and A. arborescens). Phylogenetic analyses of concatenated loci and haplotype network for every investigated locus revealed that large-spored isolates from C. arvensis exhibit a low genetic variability, suggesting common haplotypes in a broad solanaceous host range. Meanwhile, small-spored Alternaria isolates displayed high genetic diversity in all examined gene regions, indicating potential geographical haplotype distribution per HIS3 locus. Pathogenicity tests confirmed the virulence of all isolates on original hosts, with crop plants of potato and tomato also showing high susceptibility. Notably, this research documents six Alternaria species on C. arvensis in Serbia for the first time, significantly broadening our understanding of the pathogen's diversity and suggesting new sources of inoculum in solanaceous crops.

[Allergy and immunotoxicology in preventive and clinical medicine from theory to practice: Environmental factors in bronchial asthma]

BACKGROUND

According to the gene-environment interactions concept, the mechanism of health impairment can be explained by genetic factors, environmental factors, or their interaction. Physical and mental health effects resulting from environmental exposure may be classified either as toxicity, immune response, and allergic reaction. Moreover, despite the already established therapeutic approaches to bronchial asthma and decreasing mortality due to bronchial asthma, patients with difficult and severe asthma are increasing in number. This review outlines recent topics in the field of allergies, focusing on asthma.

RESULTS AND DISCUSSION

Living environment-derived pollutants and their involvement in the pathogenesis of asthma and its exacerbation, referred to here as an exposome concept, comprises the three domains of internal, specific external, and general external. Living environment-derived pollutants include exposure to pollutants in workplaces, climate change, air pollution, microplastics, tobacco smoke, biodiversity change and loss, changing dietary habits, and the microbiome. These are associated with the modernization, urbanization, and globalization of human society. Although many novel compounds are currently available, their harmful health effects, such as allergy, are not thoroughly understood. Hence, the means to mitigate these are unknown. Dietary changes from a traditional diet rich in fish to a Western-style diet are considered critical environmental factors and therefore, associated with an increased prevalence of allergies. Cytokines, including thymic stromal lymphopoietin, IL-25, and IL-33, released from the airway epithelium in response to various triggers (exposure to diverse environmental factors) are known as alarmins. Anti-alarmin antibodies are a promising therapeutic approach against severe and difficult allergic disorders. Collaboration between hospitals and clinics and occupational and clinical medicine is imperative for treating and managing severe asthma. In addition to avoiding environmental exposure, understanding the pathogenesis and exacerbation of asthma is essential for future research in the field of allergy and immunotoxicology.

Aligning spatial ecological theory with the study of clonal organisms: the case of fungal coexistence

Established ecological theory has focused on unitary organisms, and thus its concepts have matured into a form that often hinders rather than facilitates the ecological study of modular organisms. Here, we use the example of filamentous fungi to develop concepts that enable integration of non-unitary (modular) organisms into the established community ecology theory, with particular focus on its spatial aspects. In doing so, we provide a link between fungal community ecology and modern coexistence theory (MCT). We first show how community processes and predictions made by MCT can be used to define meaningful scales in fungal ecology. This leads to the novel concept of the unit of community interactions (UCI), a promising conceptual tool for applying MCT to communities of modular organisms with indeterminate clonal growth and hierarchical individuality. We outline plausible coexistence mechanisms structuring fungal communities, and show at what spatial scales and in what habitats they are most likely to act. We end by describing challenges and opportunities for empirical and theoretical research in fungal competitive coexistence.

Comparative analysis of airborne fungal spore distribution in urban and rural environments of Slovakia

Monitoring airborne fungal spores is crucial for public health and plant production since they belong to important aeroallergens and phytopathogens. Due to different land use, their concentration can differ significantly between urban and rural areas. We monitored their spectrum and quantity on two geographically close sites with a different degree of urbanisation: Bratislava City and Kaplna Village in Slovakia, located 38 km apart. We recorded the spectrum of airborne fungal spores over a year and confirmed the microscopic results by amplicon-based metagenomic analysis. The main spore season of the most frequent genera lasted over a week longer in Kaplna, but its intensity was approximately two-fold higher in Bratislava. This can be possibly connected to the microclimatic conditions of the urban area (especially wind speed and heat island effect) and the lesser use of fungicides. Cladosporium was the dominant genus on both sites, influencing the intensity most significantly. Through statistical analysis of the influence of meteorological parameters on airborne fungal spore levels, we identified a significant relationship with temperature, while the impact of other parameters varied depending on the spore type and release mechanism. Our results show the differences in airborne fungal spore levels between urban and rural areas and highlight the necessity for more monitoring stations in various environments.

Airborne Alternaria Spores: 70 Annual Records in Northwestern Spain

This study presents data on the concentration of Alternaria spores in the atmosphere of the northwestern Iberian Peninsula. A non-viable volumetric method was used to collect the samples, resulting in a database of 70 annual. When the annual averages for each locality are calculated, Ourense stands out with 2152 spores/m3, followed by Vigo and Lugo, while Santiago de Compostela recorded the lowest concentrations. Focusing on the total data for each locality, the main sporulation period started in May and ended in October in all localities, centered on a single phase, with an earlier onset and longer duration in Ourense and Vigo. The number of days with concentrations in excess of 100 spores/m3 was very low in Santiago de Compostela, Ourense, and Vigo and null in Lugo. Temperature was the meteorological parameter for which the highest statistical correlation was obtained in all locations, being favorable to the concentration of spores in the air. Temperature ranges favorable to the presence of airborne spores in the study area ranged from 25.5 to 31.2 °C. Based on the analysis of the data collected, it is concluded that Alternaria spore concentrations are low throughout most of the year.

The plant disease triangle facing climate change: a molecular perspective

Variations in climate conditions can dramatically affect plant health and the generation of climate-resilient crops is imperative to food security. In addition to directly affecting plants, it is predicted that more severe climate conditions will also result in greater biotic stresses. Recent studies have identified climate-sensitive molecular pathways that can result in plants being more susceptible to infection under unfavorable conditions. Here, we review how expected changes in climate will impact plant-pathogen interactions, with a focus on mechanisms regulating plant immunity and microbial virulence strategies. We highlight the complex interactions between abiotic and biotic stresses with the goal of identifying components and/or pathways that are promising targets for genetic engineering to enhance adaptation and strengthen resilience in dynamically changing environments.

Skin, gut, and lung barrier: Physiological interface and target of intervention for preventing and treating allergic diseases

The epithelial barriers of the skin, gut, and respiratory tract are critical interfaces between the environment and the host, and they orchestrate both homeostatic and pathogenic immune responses. The mechanisms underlying epithelial barrier dysfunction in allergic and inflammatory conditions, such as atopic dermatitis, food allergy, eosinophilic oesophagitis, allergic rhinitis, chronic rhinosinusitis, and asthma, are complex and influenced by the exposome, microbiome, individual genetics, and epigenetics. Here, we review the role of the epithelial barriers of the skin, digestive tract, and airways in maintaining homeostasis, how they influence the occurrence and progression of allergic and inflammatory conditions, how current treatments target the epithelium to improve symptoms of these disorders, and what the unmet needs are in the identification and treatment of epithelial disorders.

Identifying key environmental factors to model Alt a 1 airborne allergen presence and variation

Fungal spores, commonly found in the atmosphere, can trigger important respiratory disorders. The glycoprotein Alt a 1 is the major allergen present in conidia of the genus Alternaria and has a high clinical relevance for people sensitized to fungi. Exposure to this allergen has been traditionally assessed by aerobiological spore counts, although this does not always offer an accurate estimate of airborne allergen load. This study aims to pinpoint the key factors that explain the presence and variation of Alt a 1 concentration in the atmosphere in order to establish exposure risk periods and improve forecasting models. Alternaria spores were sampled using a Hirst-type volumetric sampler over a five-year period. The allergenic fraction from the bioaerosol was collected using a low-volume cyclone sampler and Alt a 1 quantified by Enzyme-Linked ImmunoSorbent Assay. A cluster analysis was executed in order to group days with similar environmental features and then analyze days with the presence of the allergen in each of them. Subsequently, a quadratic discriminant analysis was performed to evaluate if the selected variables can predict days with high Alt a 1 load. The results indicate that higher temperatures and absolute humidity favor the presence of Alt a 1 in the atmosphere, while time of precipitation is related to days without allergen. Moreover, using the selected parameters, the quadratic discriminant analysis to predict days with allergen showed an accuracy rate between 67 % and 85 %. The mismatch between daily airborne concentration of Alternaria spores and allergen load can be explained by the greater contribution of medium-to-long distance transport of the allergen from the major emission sources as compared with spores. Results highlight the importance of conducting aeroallergen quantification studies together with spore counts to improve the forecasting models of allergy risk, especially for fungal spores.

The Impact of Climate Change on the Sporulation of Atmospheric Fungi

The U.S. Global Change Research Program, Fourth National Climate Assessment reports that it is extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century. There are no convincing alternative explanations supported by observational evidence.

Effect of prevailing winds and land use on Alternaria airborne spore load

Alternaria spores are a common component of the bioaerosol. Many Alternaria species are plant pathogens, and their conidia are catalogued as important aeroallergens. Several aerobiological studies showing a strong relationship between concentrations of airborne spore and meteorological parameters have consequently been developed. However, the Alternaria airborne load variation has not been thoroughly investigated because it is difficult to assess their sources, as they are a very common and widely established phytopathogen. The objective of this study is to estimate the impact of vegetation and land uses as potential sources on airborne spore load and to know their influence, particularly, in cases of long-medium distance transport. The daily airborne spore concentration was studied over a 5-year period in León and Valladolid, two localities of Castilla y León (Spain), with differences in their bioclimatic and land use aspects. Moreover, the land use analysis carried out within a 30 km radius of each monitoring station was combined with air mass data in order to search for potential emission sources. The results showed a great spatial variation between the two areas, which are relatively close to each other. The fact that the spore concentrations recorded in Valladolid were higher than those in León was owing to prevailing winds originating from large areas covered by cereal crops, especially during the harvest period. However, the prevailing winds in León came from areas dominated by forest and shrubland, which explains the low airborne spore load, since the main Alternaria sources were the grasslands located next to the trap. Furthermore, the risk days in this location presented an unusual wind direction. This study reveals the importance of land cover and wind speed and direction data for establishing potential airborne routes of spore transport in order to improve the Alternaria forecasting models. The importance of conducting Alternaria aerobiological studies at a local level is also highlighted.

Alternaria spore exposure in Bavaria, Germany, measured using artificial intelligence algorithms in a network of BAA500 automatic pollen monitors

Although Alternaria spores are well-known allergenic fungal spores, automatic bioaerosol recognition systems have not been trained to recognize these particles until now. Here we report the development of a new algorithm able to classify Alternaria spores with BAA500 automatic bioaerosol monitors. The best validation score was obtained when the model was trained on both data from the original dataset and artificially generated images, with a validation unweighted mean Intersection over Union (IoU), also called Jaccard Index, of 0.95. Data augmentation techniques were applied to the training set. While some particles were not recognized (false negatives), false positives were few. The results correlated well with manual counts (mean of four Hirst-type traps), with R² = 0.78. Counts from BAA500 were 1.92 times lower than with Hirst-type traps. The algorithm was then used to re-analyze the historical automatic pollen monitoring network (ePIN) dataset (2018-2022), which lacked Alternaria spore counts. Re-analysis of past data showed that Alternaria spore exposure in Bavaria was very variable, with the highest counts in the North (Marktheidenfeld, 154 m a.s.l.), and the lowest values close to the mountains in the South (Garmisch-Partenkirchen, 735 m a.s.l.). This approach shows that in our network future algorithms can be run on past datasets. Over time, the use of different algorithms could lead to misinterpretations as stemming from climate change or other phenological causes. Our approach enables consistent, homogeneous treatment of long-term series, thus preventing variability in particle counts owing to changes in the algorithms.

Climate change, human health, and the exposome: Utilizing OMIC technologies to navigate an era of uncertainty

Climate change is an anthropogenic phenomenon that is alarming scientists and non-scientists alike. The emission of greenhouse gases is causing the temperature of the earth to rise and this increase is accompanied by a multitude of climate change-induced environmental exposures with potential health impacts. Tracking human exposure has been a major research interest of scientists worldwide. This has led to the development of exposome studies that examine internal and external individual exposures over their lifetime and correlate them to health. The monitoring of health has also benefited from significant technological advances in the field of "omics" technologies that analyze physiological changes on the nucleic acid, protein, and metabolism levels, among others. In this review, we discuss various climate change-induced environmental exposures and their potential health implications. We also highlight the potential integration of the technological advancements in the fields of exposome tracking, climate monitoring, and omics technologies shedding light on important questions that need to be answered.

Association between air pollution and the prevalence of allergic rhinitis in Chinese children: A systematic review and meta-analysis

Background: Allergic rhinitis (AR) is a common chronic inflammatory disease with bothersome symptoms. However, the effect of air pollution on the prevalence of AR in children is controversial. Objective: This study aimed to investigate the association between air pollution and the prevalence of AR in Chinese children. Methods: This study, in China, included 160,356 students ages 0-18 years who completed a questionnaire about the accuracy of the International Study of Asthma and Allergies in Childhood (ISAAC). The effect of different air pollutants on the prevalence rate were evaluated by meta-analysis. Also, it evaluated the effect of different air pollutants on the prevalence rate. Results: The differences in the effects of sulfur dioxide (SO₂) exposure (combined odds ratio [OR_combined] 1.03 [95% confidence interval {CI}, 1.01-1.05]; p = 0.010) and nitrogen dioxide (NO₂) exposure (OR_combined 1.11 [95% CI, 1.05-1.18]; p = 0.0006) on the risk of childhood AR was statistically significant. The effect of particulate matter with aerodynamic diameter of <10 μm (PM₁₀) exposure on the risk of childhood AR was statistically significant (OR_combined 1.02 [95% CI, 1.01-1.03]; p < 0.001), the effect of particulate matter with aerodynamic diameter of <2.5 μm (PM_2.5) exposure on the risk of childhood AR was statistically significant (OR_combined 1.15 [95% CI, 1.03-1.29]; p = 0.02), and the effect of ozone exposure on the risk of childhood AR was not statistically significant (OR_combined 0.98 [95% CI, 0.67-1.41]; p = 0.13). Conclusion: NO₂, SO₂, PM_2.5, and PM₁₀ were associated with the prevalence of AR in Chinese children. PM_2.5 had the highest correlation with AR prevalence.

Climate change impact on fungi in the atmospheric microbiome

The atmospheric microbiome is one of the least studied microbiomes of our planet. One of the most abundant, diverse and impactful parts of this microbiome is arguably fungal spores. They can be very potent outdoor aeroallergens and pathogens, causing an enormous socio-economic burden on health services and annual damages to crops costing billions of Euros. We find through hypothesis testing that an expected warmer and drier climate has a dramatic impact on the atmospheric microbiome, conceivably through alteration of the hydrological cycle impacting agricultural systems, with significant differences in leaf wetness between years (p-value <0.05). The data were measured via high-throughput sequencing analysis using the DNA barcode marker, ITS2. This was complemented by remote sensing analysis of land cover and dry matter productivity based on the Sentinel satellites, on-site detection of atmospheric and vegetation variables, GIS analysis, harvesting analysis and footprint modelling on trajectory clusters using the atmospheric transport model HYSPLIT. We find the seasonal spore composition varies between rural and urban zones reflecting both human activities (e.g. harvest), type and status of the vegetation and the prevailing climate rather than mesoscale atmospheric transport. We find that crop harvesting governs the composition of the atmospheric microbiome through a clear distinction between harvest and post-harvest beta-diversity by PERMANOVA on Bray-Curtis dissimilarity (p-value <0.05). Land cover impacted significantly by two-way ANOVA (p-value <0.05), while there was minimal impact from air mass transport over the 3 years. The hypothesis suggests that the fungal spore composition will change dramatically due to climate change, an until now unforeseen effect affecting both food security, human health and the atmospheric hydrological cycle. Consequently the management of crop diseases and impact on human health through aeroallergen exposure need to consider the timing of crop treatments and land management, including post harvest, to minimize exposure of aeroallergens and pathogens.

Climate Change and Effects on Molds and Mycotoxins

Earth’s climate is undergoing adverse global changes as an unequivocal result of anthropogenic activity. The occurring environmental changes are slowly shaping the balance between plant growth and related fungal diseases. Climate (temperature, available water, and light quality/quantity; as well as extreme drought, desertification, and fluctuations of humid/dry cycles) represents the most important agroecosystem factor influencing the life cycle stages of fungi and their ability to colonize crops, survive, and produce toxins. The ability of mycotoxigenic fungi to respond to Climate Change (CC) may induce a shift in their geographical distribution and in the pattern of mycotoxin occurrence. The present review examines the available evidence on the impact of CC factors on growth and mycotoxin production by the key mycotoxigenic fungi belonging to the genera Aspergillus, Penicillium, and Fusarium, which include several species producing mycotoxins of the greatest concern worldwide: aflatoxins (AFs), ochratoxins, and fumonisins (FUMs).

Environmental drivers of the seasonal exposure to airborne Alternaria spores in Spain

Alternaria conidia have high allergenic potential and they can trigger important respiratory diseases. Due to that and to their extensive detection period, airborne Alternaria spores are considered as a relevant airborne allergenic particle. Several studies have been developed in order to predict the human exposure to this aeroallergen and to prevent their negative effects on sensitive population. These studies revealed that some sampling locations usually have just one single Alternaria spore season while other locations generally have two seasons within the same year. However, the reasons of these two different seasonal patterns remain unclear. To understand them better, the present study was carried out in order to determine if there are any weather conditions that influence these different behaviours at different sampling locations. With this purpose, the airborne Alternaria spore concentrations of 18 sampling locations in a wide range of latitudinal, altitudinal and climate ranges of Spain were studied. The aerobiological samples were obtained by means of Hirst-Type volumetric pollen traps, and the seasonality of the airborne Alternaria spores were analysed. The optimal weather conditions for spore production were studied, and the main weather factor affecting Alternaria spore seasonality were analysed by means of random forests and regression trees. The results showed that the temperature was the most relevant variable for the Alternaria spore dispersion and it influenced both the spore integrals and their seasonality. The water availability was also a very significant variable. Warmer sampling locations generally have a longer period of Alternaria spore detection. However, the spore production declines during the summer when the temperatures are extremely warm, what splits the favourable period for Alternaria spore production and dispersion into two separate ones, detected as two Alternaria spore seasons within the same year.

Epithelial barrier hypothesis: Effect of the external exposome on the microbiome and epithelial barriers in allergic disease

Environmental exposure plays a major role in the development of allergic diseases. The exposome can be classified into internal (e.g., aging, hormones, and metabolic processes), specific external (e.g., chemical pollutants or lifestyle factors), and general external (e.g., broader socioeconomic and psychological contexts) domains, all of which are interrelated. All the factors we are exposed to, from the moment of conception to death, are part of the external exposome. Several hundreds of thousands of new chemicals have been introduced in modern life without our having a full understanding of their toxic health effects and ways to mitigate these effects. Climate change, air pollution, microplastics, tobacco smoke, changes and loss of biodiversity, alterations in dietary habits, and the microbiome due to modernization, urbanization, and globalization constitute our surrounding environment and external exposome. Some of these factors disrupt the epithelial barriers of the skin and mucosal surfaces, and these disruptions have been linked in the last few decades to the increasing prevalence and severity of allergic and inflammatory diseases such as atopic dermatitis, food allergy, allergic rhinitis, chronic rhinosinusitis, eosinophilic esophagitis, and asthma. The epithelial barrier hypothesis provides a mechanistic explanation of how these factors can explain the rapid increase in allergic and autoimmune diseases. In this review, we discuss factors affecting the planet's health in the context of the 'epithelial barrier hypothesis,' including climate change, pollution, changes and loss of biodiversity, and emphasize the changes in the external exposome in the last few decades and their effects on allergic diseases. In addition, the roles of increased dietary fatty acid consumption and environmental substances (detergents, airborne pollen, ozone, microplastics, nanoparticles, and tobacco) affecting epithelial barriers are discussed. Considering the emerging data from recent studies, we suggest stringent governmental regulations, global policy adjustments, patient education, and the establishment of individualized control measures to mitigate environmental threats and decrease allergic disease.

Spatiotemporal assessment of aeromycoflora under differing urban green space, sampling height, and meteorological regimes: the atmospheric fungiscape of Thessaloniki, Greece

We studied the diversity and abundance of the airborne fungal spores in the city of Thessaloniki, Greece, for two consecutive years. Air samples were collected at one rooftop station (at 30 m) and six near-ground stations (at 1.5 m) that differed in the size and composition of adjacent green spaces. The effects of meteorological factors on airborne fungal spore concentrations were also explored. Cladosporium spores were dominant everywhere in the air of the city. The total concentration of the airborne fungal spores at 30 m was 10 times lower than near the ground. Differences in concentration and composition were far less pronounced among near-ground stations. The attributes of the fungal spore season did not change in a consistent way among stations and years. Concentrations at the near-ground stations matched the grouping of the latter into stations of high, intermediate, and low urban green space. Minimum air temperature was the primary meteorological factor affecting spore abundance, followed by relative humidity. Airborne fungal spores are more homogeneously distributed in the air of the city, but their concentrations decrease more rapidly with height than pollen.

Metatranscriptomic Analyses Reveal the Functional Role of Botrytis cinerea in Biochemical and Textural Changes during Noble Rot of Grapevines

Botrytis cinerea, can lead to the formation of noble rot (NR) of grape berries under certain environmental conditions, resulting in favored metabolic and physical changes necessary for producing highly regarded botrytized wines. The functional genes involved in the textural and biochemical processes are still poorly characterized. We generated and analyzed metatranscriptomic data from healthy (H) berries and from berries representing the four stages of NR from the Tokaj wine region in Hungary over three months. A weighted gene co-expression network analysis (WGCNA) was conducted to link B. cinerea functional genes to grape berry physical parameters berry hardness (BH), berry skin break force (F_sk), berry skin elasticity (E_sk), and the skin break energy (W_sk). Clustered modules showed that genes involved in carbohydrate and protein metabolism were significantly enriched in NR, highlighting their importance in the grape berry structural integrity. Carbohydrate active enzymes were particularly up-regulated at the onset of NR (during the transition from phase I to II) suggesting that the major structural changes occur early in the NR process. In addition, we identified genes expressed throughout the NR process belonging to enriched pathways that allow B. cinerea to dominate and proliferate during this state, including sulphate metabolizing genes and genes involved in the synthesis of antimicrobials.

Airborne Alt a 1 Dynamic and Its Relationship with the Airborne Dynamics of Alternaria Conidia and Pleosporales Spores

Fungal spores are universal atmospheric components associated to allergic reactions. Alternaria (Ascomycota) is considered the most allergenic spore taxa. Alt a 1 is the major allergen of Alternaria and is present also in other Pleosporales. In this study, standard Hirst-based sampling and analyzing methods for measuring spore daily concentrations of Alternaria, Curvularia, Drechslera-Helminthosporium, Epicoccum, Leptosphaeria, Pithomyces, Pleospora and Stemphylium (all included in the taxon Pleosporales) have been used as well as two high-volume samplers, Burkard Cyclone (2017) and MCV CAV-A/mb (2019–2020), and ELISA kits for measuring the allergen. The detection and quantification of Alt a 1 was only possible in the samples from the MCV sampler. Although Alt a 1 was better correlated with Alternaria spores than with Pleosporales spores, the three of them showed high correlations. It is shown that there is a high and significant correlation of Alt a 1 with temperature, a negative correlation with relative humidity and no correlation with precipitation. The aerobiological monitoring of these three elements ensures the best information for understanding the affectation to allergy sufferers, but, if this is not possible, as a minimum public health service aimed at the detection, treatment and prevention of allergies, the study of the airborne Alternaria spores should be ensured.

[Outdoor aeroallergens and climate change]

INTRODUCTION

Pollen and fungal spore concentrations in outdoor air are partly dependent on atmospheric conditions. Since the climate is changing, there is a growing body of research on the effects of climate change on aeroallergens. The present article provides a rapid review of this literature, highlighting the points of agreement, but also drawing attention to the main mistakes to be avoided.

STATE OF ART

For pollen, the prevailing view is that rising temperatures lead to an earlier start to the pollen season, a longer season, increased allergenic potential and higher concentrations. However, there are exceptions: what is true for one taxon, in one place and at one time, can almost never be generalised. For fungal spores, it is even more difficult to state universal rules.

PERSPECTIVES

Four priorities can be set for future research: (1) to look for trends only on sufficiently long series and not to neglect possible trend reversals; (2) to give priority to the local scale and the separate consideration of the various pollen and mycological taxa; (3) not to limit oneself to temperature as an element of explanation, but also to consider the other elements of the climate; (4) not to try to explain any evolution in the abundance or seasonality of aeroallergens by climate change alone.

CONCLUSIONS

Many more analytical studies giving precedence to observation over reasoning are still required, without any preconceptions, before it is possible to synthesise the impacts of climate change on pollen and, even more so, on fungal spores.

Aerobiological modeling I: A review of predictive models

The present work is the first of two reviews on applied modeling in the field of aerobiology. The aerobiological predictive models for pollen and fungal spores, usually defined as predictive statistical models, will, amongst other objectives, forecast airborne particles' concentration or dynamical behavior of the particles. These models can be classified into Observation Based Models (OBM), Phenological Based Models (PHM), or OTher Models (OTM). The aim of this review is to show, analyze and discuss the different predictive models used in pollen and spore aerobiological studies. The analysis was performed on published electronic scientific articles from 1998 to 2016 related to the type of model, the taxa and the modelled parameters. From a total of 503 studies, 55.5% used OBM (44.8% on pollen and 10.7% on fungal spores), 38.5% PHM (all on pollen) and 6% OTM (5.4% on pollen and 0.6% on fungal spores). OBM have been used with high frequency to forecast concentration. The most frequent model of OBM was linear regression (18.5% out of 503) on pollen and artificial neural networks (4.6%) on fungal spores. In the PHM, the principal use was to characterize the main pollen season (flowering season) based on the model of growth degree days. Finally, OTM have been used to estimate concentrations at unmonitored areas. Olea (14,5%) on pollen and Alternaria (4,8%) on fungal spores were the taxa most frequently modelled. Daily concentration was the most modelled parameter by OBM (25.2%) and season start day by PHM (35.6%). The PHM approaches include greater model diversity and use fewer independent variables than OBM. In addition, PHM show to be easier to apply than OBM; however, the wide range of criteria to define the parameters to use in PHM (e.g.: pollination start day) makes that each model is used with a lesser frequency than other models.

The Effect of Artificial Media and Temperature on the Growth and Development of the Honey Bee Brood Pathogen Ascosphaera apis

Ascosphaera apis is a causative agent of chalkbrood, which is one of the most widespread honey bee diseases. In our experiments, the influence of several artificial media and cultivation under different temperatures was evaluated. Concretely, the radial growth of separated mating types was measured, reproductive structures in a Neubauer hemocytometer chamber were counted simultaneously, and the morphometry of spore cysts and spore balls was assessed. The complex set of experiments determined suitable cultivation conditions. A specific pattern between reproductive structure size and temperature was found. The optimal temperature for both mating types was 30 °C. SDA and YGPSA media are suitable for fast mycelial growth. Moreover, the effect of bee brood on fungus growth and development in vitro was investigated by modification of culture medium. The newly modified medium PDA-BB4 was most effective for the production of the reproductive structures. The result suggests that honey bee brood provides necessary nutrients for proper fungus development during in vitro cultivation. As there is no registered therapeutic agent against chalkbrood in most countries, including the European Union, the assessment of A. apis growth and development in different conditions could help to understand fungus pathogenesis and thus control chalkbrood disease.

The fungal sexual revolution continues: discovery of sexual development in members of the genus Aspergillus and its consequences

Asexuality was considered to be a common feature of a large part of fungi, including those of the genus Aspergillus. However, recent advances and the available genomic and genetic engineering technologies allowed to gather more and more indications of a hidden sexuality in fungi previously considered asexual. In parallel, the acquired knowledge of the most suitable conditions for crossings was shown to be crucial to effectively promote sexual reproduction in the laboratory. These discoveries not only have consequences on our knowledge of the biological processes ongoing in nature, questioning if truly asexual fungal species exist, but they also have important implications on other research areas. For instance, the presence of sexuality in certain fungi can have effects on their pathogenicity or on shaping the ecosystem that they normally colonize. For these reasons, further investigations of the sexual potential of Aspergillus species, such as the industrially important A. niger, will be carried on.

Toxigenic Fungi and Mycotoxins in a Climate Change Scenario: Ecology, Genomics, Distribution, Prediction and Prevention of the Risk

Toxigenic fungi and mycotoxins are very common in food crops, with noticeable differences in their host specificity in terms of pathogenicity and toxin contamination. In addition, such crops may be infected with mixtures of mycotoxigenic fungi, resulting in multi-mycotoxin contamination. Climate represents the key factor in driving the fungal community structure and mycotoxin contamination levels pre- and post-harvest. Thus, there is significant interest in understanding the impact of interacting climate change-related abiotic factors (especially increased temperature, elevated CO2 and extremes in water availability) on the relative risks of mycotoxin contamination and impacts on food safety and security. We have thus examined the available information from the last decade on relative risks of mycotoxin contamination under future climate change scenarios and identified the gaps in knowledge. This has included the available scientific information on the ecology, genomics, distribution of toxigenic fungi and intervention strategies for mycotoxin control worldwide. In addition, some suggestions for prediction and prevention of mycotoxin risks are summarized together with future perspectives and research needs for a better understanding of the impacts of climate change scenarios.

An Overview of Rising CO₂ and Climatic Change on Aeroallergens and Allergic Diseases

There are a number of implications of climate change in regard to human health. Among these, the role of rising carbon dioxide (CO₂) and temperature in aeroallergen exposure and associated changes in the start, duration and intensity of the pollen season, and associated consequences in aeroallergens and allergic disease are a primary concern. This review is intended to provide a synopsis of CO₂ and climate factors associated with likely changes in aeroallergen biology (indoor and outdoor), including changes in the demography of flowering plants, pollen seasonality, aeroallergen production, and potential biotic and abiotic interactions. These factors, in turn, are compared to clinical trials that have linked aeroallergens to allergic disease and associated health impacts. Finally, suggestions to address unmet needs and critical knowledge gaps are offered. Such recommendations are not meant to be inclusive, but to serve as a spur for the additional research and resources that will be necessary to acquire a better understanding of climate change, CO₂, aeroallergens and associated allergic diseases. Such resources will be critical to derive time-relevant scientific and policy solutions that will minimize public health consequences in a changing climate.

Alternaria Leaf Spot Caused by Alternaria Species: An Emerging Problem on Ornamental Plants in Italy

Serious outbreaks of Alternaria leaf spot and plant decay have recently been recorded on several ornamental plants in the Biella Province (Northern Italy). Twenty-two fungal isolates were obtained from Alternaria infected plant tissues from 13 ornamental hosts. All the isolates were identified morphologically as small-spored Alternaria species. Multilocus sequence typing, carried out by means of ITS, rpb2, tef1, endoPG, Alt a 1, and OPA10-2, assigned 19 isolates as Alternaria alternata, two isolates as belonging to the Alternaria arborescens species complex, and one isolate as an unknown Alternaria sp. Haplotype analyses of ornamental and reference A. alternata isolates from 12 countries identified 14 OPA10-2 and 11 endoPG haplotypes showing a relatively high haplotype diversity. A lack of host specialization or geographic distribution was observed. The host range of the studied A. alternata isolates expanded in cross-pathogenicity assays, and more aggressiveness was frequently observed on the experimental plants than on the host plants from which the fungal isolates were originally isolated. High disease severity, population expansion, intraspecies diversity, and increased range of experimental hosts were seen in the emergence of Alternaria disease on ornamentals. More epidemiological and molecular studies should be performed to better understand these diseases, taking into consideration factors such as seed transmission and ongoing climate changes.

The rising of allergic respiratory diseases in a changing world: from climate change to migration

INTRODUCTION

The rising of allergic respiratory diseases (ARDs) suggests a decisive role of environmental factors, that have dramatically changed in the last decades.

AREAS COVERED

This review addresses various aspects of the external exposome acting on the development, progression, clinical presentation and severity of ARDs. Climate change, air pollution and biodiversity loss act directly and through their complex interactions on atopic risk: reacent foundings on these aspects are discussed herein. The review also focuses on migration studies, underling the possible role of migrant status as an experimental model to study environment effects on atopy onset and progression.

EXPERT OPINION

Future perspective on this topic include prevention and mitigation strategies in regard to pollution and climate change, improvement of environmental monitoring methods, implementation of public health policies, further advances in 'omics' research and knowledge, prospective and immunological research on migrant populations and new policies to face human mobility.

Logistic regression models for predicting daily airborne Alternaria and Cladosporium concentration levels in Catalonia (NE Spain)

Alternaria and Cladosporium are the most common airborne fungal spores responsible for health problems, as well as for crop pathologies. The study of their behavior in the air is a necessary step for establishing control and prevention measures. The aim of this paper is to develop a logistic regression model for predicting the daily concentrations of airborne Alternaria and Cladosporium fungal spores from meteorological variables. To perform the logistic regression analysis, the concentration levels are binarized using concentration thresholds. The fungal spore data have been obtained at eight aerobiological monitoring stations of the Aerobiological Network of Catalonia (NE Spain). The meteorological data used were the maximum and minimum daily temperatures and daily rainfall provided by the meteorological services. The relationship between the meteorological variables and the fungal spore levels has been modeled by means of logistic regression equations, using data from the period 1995-2012. Values from years 2013-2014 were used for validation. In the case of Alternaria, three equations for predicting the presence and the exceedance of the thresholds 10 and 30 spores/m³ have been established. For Cladosporium, four equations for the thresholds 200, 500, 1000, and 1500 spores/m³ have been established. The temperature and cumulative rainfall in the last 3 days showed a positive correlation with airborne fungal spore levels, while the rain on the same day had a negative correlation. Sensitivity and specificity were calculated to measure the predictive power of the model, showing a reasonable percentage of correct predictions (ranging from 48 to 99%). The simple equations proposed allow us to forecast the levels of fungal spores that will be in the air the next day, using only the maximum and minimum temperatures and rainfall values provided by weather forecasting services.

Asexual reproduction and growth rate: independent and plastic life history traits in Neurospora crassa

Trade-offs among traits influencing fitness are predicted by life history theory because resources allocated to one function are unavailable to another. Here we examine the relationship between two such traits, asexual reproduction and growth rate, in the filamentous fungus Neurospora crassa, where shared genetic and physiological factors and a source-sink energetic relationship between growth and reproduction may constrain the evolution of these traits. To test growth-reproduction relationships in this species, we independently selected on mycelial growth rate or asexual spore production in a heterogeneous lab-derived population and evaluated the response of the non-selected traits. Combined with phenotypes for the 20 wild strains used to produce the heterogeneous population and the genome-wide genotypes of 468 strains, these data show that growth and reproduction are highly plastic in N. crassa and do not trade off either among wild strains or after laboratory selection in two environments. Rather, we find no predictable growth-reproduction relationship in the environments tested, indicating an effective absence of genetic constraint between these traits. Our results suggest that growth rate and asexual reproduction may not respond predictably to environmental change and suggest that reliance on a single trait as a proxy for fitness in fungal studies may be inadvisable.

Airborne Alternaria and Cladosporium fungal spores in Europe: Forecasting possibilities and relationships with meteorological parameters

Airborne fungal spores are prevalent components of bioaerosols with a large impact on ecology, economy and health. Their major socioeconomic effects could be reduced by accurate and timely prediction of airborne spore concentrations. The main aim of this study was to create and evaluate models of Alternaria and Cladosporium spore concentrations based on data on a continental scale. Additional goals included assessment of the level of generalization of the models spatially and description of the main meteorological factors influencing fungal spore concentrations. Aerobiological monitoring was carried out at 18 sites in six countries across Europe over 3 to 21 years depending on site. Quantile random forest modelling was used to predict spore concentrations. Generalization of the Alternaria and Cladosporium models was tested using (i) one model for all the sites, (ii) models for groups of sites, and (iii) models for individual sites. The study revealed the possibility of reliable prediction of fungal spore levels using gridded meteorological data. The classification models also showed the capacity for providing larger scale predictions of fungal spore concentrations. Regression models were distinctly less accurate than classification models due to several factors, including measurement errors and distinct day-to-day changes of concentrations. Temperature and vapour pressure proved to be the most important variables in the regression and classification models of Alternaria and Cladosporium spore concentrations. Accurate and operational daily-scale predictive models of bioaerosol abundances contribute to the assessment and evaluation of relevant exposure and consequently more timely and efficient management of phytopathogenic and of human allergic diseases.

Effects of high temperatures and drought during anthesis and grain filling period on wheat processing quality and underlying gluten structural changes

BACKGROUND

Climate changes do not only affect wheat yield, but also its quality. Information on this topic gathered so far is somewhat contradictory and insufficient. Climate changes also affect wheat indirectly through their influence on the ecosystem, including insects and fungi that affect wheat technological quality. The aim of this study was to examine trends in structural and technological changes of wheat quality under conditions typical of climate changes. With this in mind, three groups of wheat varieties with the same Glu-score were examined in three production years, characterized by different production conditions.

RESULTS

A production season characterized by climate change conditions results in lower activity of amylolytic enzymes. What is more, it results in lower content of gluten, higher gluten index value, its decrease after 1 h to 37 °C, lower number of free SH groups and higher content of free amino groups, which result in lower alveograph W, lower farinograph WA and higher extensograph dough resistance.

CONCLUSION

Variability in wheat quality produced under different climatic conditions is mainly influenced by the production conditions, including their influence on ecosystem factors. The influence of wheat cultivar genetic predisposition is much less expressed. This indicates that differences among cultivars with different Glu-score might be diminished under the influence of altered production conditions, as a consequence of climate change. © 2017 Society of Chemical Industry.

Fungal community dynamics during a marine dinoflagellate (Noctiluca scintillans) bloom

Contamination and eutrophication have caused serious ecological events (such as algal bloom) in coastal area. During this ecological process, microbial community structure is critical for algal bloom succession. The diversity and composition of bacteria and archaea communities in algal blooms have been widely investigated; however, those of fungi are poorly understood. To fill this gap, we used pyrosequencing and correlation approaches to assess fungal patterns and associations during a dinoflagellate (Noctiluca scintillans) bloom. Phylum level fungal types were predominated by Ascomycota, Chytridiomycota, Mucoromycotina, and Basidiomycota. At the genus level drastic changes were observed with Hysteropatella, Malassezia and Saitoella dominating during the initial bloom stage, while Malassezia was most abundant (>50%) during onset and peak-bloom stages. Saitoella and Lipomyces gradually became more abundant and, in the decline stage, contributed almost 70% of sequences. In the terminal stage of the bloom, Rozella increased rapidly to a maximum of 50-60%. Fungal population structure was significantly influenced by temperature and substrate (N and P) availability (P < 0.05). Inter-specific network analyses demonstrated that Rozella and Saitoella fungi strongly impacted the ecological trajectory of N. scintillans. The functional prediction show that symbiotrophic fungi was dominated in the onset stage; saprotroph type was the primary member present during the exponential growth period; whereas pathogentroph type fungi enriched in decline phase. Overall, fungal communities and functions correlated significantly with N. scintillans processes, suggesting that they may regulate dinoflagellate bloom fates. Our results will facilitate deeper understanding of the ecological importance of marine fungi and their roles in algal bloom formation and collapse.

Aerobiology in the International Journal of Biometeorology, 1957-2017

Aerobiology and biometeorology are related fields. Here we provide a broad review of aerobiology articles published in the International Journal of Biometeorology (IJB) over the past 60 years. We consider how the quantity of such work has varied over this period as well as which regions and countries have been the focus of such work, and where there is a relative paucity. We then focus on a number of highlights and themes in this research, including aerobiology and climate change and aerobiological modelling and forecasting. While much of the article focusses on airborne pollen research, we also discuss the extent to which other airborne organic particles such as fungal spores and bacteria have been the focus of research published in IJB. Also considered are knowledge gaps and research needs and priorities with respect to the field of aerobiology. While the IJB has been one of the main platforms for presenting aerobiological research over recent decades, the article highlights the need for the field of aerobiology to embrace new sampling technologies such as spectral analysis and next-generation sequencing to identify and quantify airborne biological particles.

Past, present and future of the climate and human health commission

The following paper presents the history of the Climate and Human Health Commission at the International Society of Biometeorology after more than one decade since its creation. A brief history of the origins of the human biometeorology is revealed through some of the main research topics and publications of the founders of the society in this field. Secondly, it is presented as a brief review of the activities of the commission in the last 10 years, based on the reports that have periodically been submitted by members of the commission to the Bulletin of the society. A summary of the topics of interest on human biometeorology and the most frequent research topics are also described. Thirdly, the need of adapting human biometeorology contents, methods and techniques to a changing world is articulated according to some of the new environmental threats in the XXI century. Finally, a list of future actions and research lines collected through a form from members of the commission is presented. The paper concludes with the existence of great challenge for human biometeorology in order to transform biometeorological knowledge into specific services to improve the wellbeing of human beings.

Estimating the abundance of airborne pollen and fungal spores at variable elevations using an aircraft: how high can they fly?

Airborne pollen and fungal spores are monitored mainly in highly populated, urban environments, for allergy prevention purposes. However, their sources can frequently be located outside cities' fringes with more vegetation. So as to shed light to this paradox, we investigated the diversity and abundance of airborne pollen and fungal spores at various environmental regimes. We monitored pollen and spores using an aircraft and a car, at elevations from sea level to 2,000 m above ground, in the region of Thesssaloniki, Greece. We found a total of 24 pollen types and more than 15 spore types. Pollen and spores were detected throughout the elevational transect. Lower elevations exhibited higher pollen concentrations in only half of plant taxa and higher fungal spore concentrations in only Ustilago. Pinaceae and Quercus pollen were the most abundant recorded by airplane (>54% of the total). Poaceae pollen were the most abundant via car measurements (>77% of the total). Cladosporium and Alternaria spores were the most abundant in all cases (aircraft: >69% and >17%, car: >45% and >27%, respectively). We conclude that pollen and fungal spores can be diverse and abundant even outside the main source area, evidently because of long-distance transport incidents.

Madeira-a tourist destination for asthma sufferers

Madeira Island is a famous tourist destination due to its natural and climatic values. Taking into account optimal weather conditions, flora richness and access to various substrates facilitating fungal growth, we hypothesised a very high risk of elevated fungal spore and pollen grain concentrations in the air of Funchal, the capital of Madeira. Concentration levels of the most allergenic taxa were measured from 2003 to 2009, using a 7-day volumetric air sampler, followed by microscopy analysis. Dependence of bioaerosols on the weather conditions and land use were assessed using spatial and statistical tools. Obtained results were re-visited by a comparison with hospital admission data recorded at the Dr. Nélio Mendonça Hospital in Funchal. Our results showed that despite propitious climatic conditions, overall pollen grain and fungal spore concentrations in the air were very low and did not exceed any clinically established threshold values. Pollen and spore peak concentrations also did not match with asthma outbreaks in the winter. Identification of places that are "free" from biological air pollution over the summer, such as Madeira Island, is very important from the allergic point of view.

Warm and dry weather accelerates and elongates Cladosporium spore seasons in Poland

Temperature is the environmental factor that systematically changes for decades and, as in plants and animals, can significantly affect the growth and development of fungi, including the abundance of their sporulation. During the time of study (2010-2012), a rapid increase in air temperature was observed in Poland, which coincided with the substantial decrease in rainfall. The increase in annual mean temperatures at three monitoring sites of this study was 0.9 °C in Lublin and Rzeszow (east Poland) and 2.0 °C in Poznan (west Poland). Such warming of air masses was comparable to the average global air temperature rise in the period of 1880-2012 accounting for 0.85 °C, as reported by the Intergovernmental Panel on Climate Change. Moreover, there was a substantial decrease in rainfall, ranging from 32.7 % (Poznan) to 43.0 % (Rzeszow). We have demonstrated that under such conditions the mean and median values of total Cladosporium spore counts significantly increased and the spore seasons were greatly accelerated. Moreover, earlier start and later end of the season caused its extension, lasting from over 20 days in Rzeszow to around 60 days in Lublin and Poznan, when the cumulative amount of 5-95 % of spores was considered. The time of reaching the cumulative amount of 50 % of spores was up to 25 days earlier (difference in Poznan between 2010 and 2012). There was also a striking acceleration of the date of the maximal Cladosporium spore concentration per cubic metre of air (26 days for Lublin, 43 for Poznan and 56 for Rzeszow).