High Spore Concentrations Research Articles

Pseudomonas chlororaphis Metabolites Reduce MfCYP51 Expression and Yield Synergistic Efficacy in Mixture with Reduced Rates of Propiconazole Against DMI-Resistant Monilinia fructicola Isolates.

Brown rot caused by Monilinia fructicola is one of the most important diseases affecting peach production in the southeastern United States. Management often involves the use of demethylation inhibitor (DMI) fungicides, but efficacy can be compromised because of overexpression of the MfCYP51 gene encoding the 14α-demethylase of the ergosterol biosynthesis pathway. This study aimed to investigate the influence of the biorational fungicide Howler EVO containing Pseudomonas chlororaphis ASF009 metabolites on the expression of MfCYP51 in M. fructicola and associated synergy with a DMI fungicide for control of DMI-resistant strains. Mycelia from two DMI-sensitive and three DMI-resistant M. fructicola isolates were exposed or not to propiconazole (0.3 μg/ml), Howler (88.1 μg/ml), or the combination propiconazole + Howler for 6 h prior to RNA extraction. Real-time PCR indicated that Howler reduced the constitutive expression of MfCYP51 in DMI-sensitive and two of three DMI-resistant isolates. Propiconazole-induced expression of the DMI target gene was significantly reduced by Howler and by the mixture of Howler plus propiconazole in all isolates. Detached fruit studies on apple revealed that the combination of Howler plus a reduced label rate of Mentor (50 μg/ml propiconazole) was synergistic against brown rot caused by a DMI-resistant isolate in high and low inoculum spore concentration experiments (synergy values of 40.1 and 4.9, respectively). We hypothesize that the synergistic effects against M. fructicola resistant to DMI fungicides based on MfCYP51 gene overexpression can be attributed to reduced 14α demethylase production due to transcription inhibition, which may necessitate fewer DMI fungicide molecules to arrest fungal growth. The use of Howler/DMI mixtures for brown rot control warrants further investigation because such mixtures could potentially allow for reduced DMI fungicide use rates in the field without compromising yield or increased resistance selection.

Hormetic effect induced by Beauveria bassiana in Myzus persicae.

Myzus persicae, a serious sap-sucking pest of a large variety of host plants in agriculture, is traditionally controlled using chemical insecticides but there isinterestin using biopesticides as restrictions are increasingly placed on the use of broad-spectrum pesticides. Here, we show that in Petri dish experiments, high concentrations of the fungal entomopathogen Beauveria bassiana led to rapid mortality of M. persicae, although at a low concentration (1 × 104 conidia mL-1) there is a hormetic effect in which survival and fecundity are enhanced. Hormetic effects persisted across a generation with reduced development time and increased fecundity in the offspring of M. persicae exposed to B. bassiana. The whole-plant experiment points to a hormetic effect being detected in two out of three tested lines. The impact of these effects might also depend on whether M. persicae was transinfected with the endosymbiont Rickettsiella viridis, which decreases fecundity and survival compared with aphids lacking this endosymbiont. This fecundity cost was ameliorated in the generation following exposure to the entomopathogen. Although B. bassiana is effective in controlling M. persicae especially at higher spore concentrations, utilization of this entomopathogen requires careful consideration of hormetic effects at lower spore concentrations, and further research to optimize its application for sustainable agriculture is recommended. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

How does parasite environmental transmission stage concentration change before, during, and after disease outbreaks?

Outbreaks of environmentally transmitted parasites require that susceptible hosts encounter transmission stages in the environment and become infected, but we also know that transmission stages can be in the environment without triggering disease outbreaks. One challenge in understanding the relationship between environmental transmission stages and disease outbreaks is that the distribution and abundance of transmission stages outside of their hosts have been difficult to quantify. Thus, we have limited data about how changes in transmission stage abundance influence disease dynamics; moreover, we do not know whether the relationship between transmission stages and outbreaks differs among parasite species. We used digital PCR to quantify the environmental transmission stages of five parasites in six lakes in southeastern Michigan every 2 weeks from June to November 2021. At the same time, we quantified infection prevalence in hosts and host density. Our study focused on eight zooplankton host species (Daphnia spp. and Ceriodaphnia dubia) and five of their parasites from diverse taxonomic groups (bacteria, yeast, microsporidia, and oomycete) with different infection mechanisms. We found that parasite transmission stage concentration increased prior to disease outbreaks for all parasites. However, parasites differed significantly in the relative timing of peaks in transmission stage concentration and infection outbreaks. The "continuous shedder" parasites had transmission stage peaks at the same time as or slightly after the outbreak peaks. In contrast, parasites relying on host death for transmission ("obligate killers") had transmission stage peaks before outbreak peaks. For most parasites, lakes with outbreaks had higher spore concentrations than those without outbreaks, especially once an outbreak began; the exception was for a parasite, Pasteuria ramosa, with very strong genotypic specificity of infection. Overall, our results show that disease outbreaks are tightly linked to transmission stage concentration; outbreaks were preceded by increases in transmission stage concentration in the environment and then were fueled by the production of more transmission stages during the outbreak itself, with concentrations decreasing to pre-outbreak levels as outbreaks waned. Thus, tracking transmission stages in the environment improves our understanding of the drivers of disease outbreaks and reveals how parasite traits may affect these dynamics.

Virulence of Local Isolates of The Entomopathogenic Fungus Beauveria bassiana on Egg and Adult Stages of Tomato Leaf Miner, Tuta absoluta

Hasan, A.H., M. Ahmad, O. Hamoudi and M. Moufleh. 2024. Virulence of Local Isolates of The Entomopathogenic Fungus Beauveria bassiana on Egg and Adult Stages of Tomato Leaf Miner, Tuta absoluta. Arab Journal of Plant Protection, 42(3): 340-348. https://doi.org/10.22268/AJPP-001252 The efficacy of four local isolates of the entomopathogenic fungus Beauveria bassiana (Ascomycota: Hypocreales), (b6 isolated from citrus orchard soil (Harisoon), b7 from greenhouse soil (Alkhrab), b8 from palm weevil pupae (Lattakia) and b10 from olive orchard soil (Mengella), were tested on the egg and adult stages of the tomato leafminer Tuta absoluta by direct spraying for each stage with three different concentrations of fungal spore suspensions 2×104 , 2×106 and 2×108 spores/ml. The results obtained showed that both insect stages were very sensitive to fungal infection to varying degrees and there were significant differences in the hatching rate and adult mortality rate caused by the four isolates in comparison with the control treatment. The b8 and b10 isolates were the most effective on both insect stages at all concentrations tested. Corrected mortality rates at the highest concentration (2×108 spore/ml) were 82.59% for b8 isolate and 86.30% for b10 isolate on eggs and LC50 was 1×106 spores/ml for b8 isolate and 8×105 spores/ml for b10 isolate, whereas the corrected mortality rate for both were 100% on adults, 8 days after treatment, and by using the highest spore concentration. The LT50 was 3.2 days for both isolates and the LC50 was 2×104 spores/ml for b8 isolate and 1×105 spores/ml for b10 isolate under laboratory conditions. Keywords: Biological control, Beauveria bassiana, Tuta absoluta, mortality, LT50, LC50

Evaluation of Amisulbrom Products for the Management of Clubroot of Canola (Brassica napus).

Clubroot, caused by Plasmodiophora brassicae, is an important disease of canola (Brassica napus). Amisulbrom, a quinone inside inhibitor (QiI), was evaluated for its effectiveness in clubroot management in Alberta, Canada. Resting spores of P. brassicae were treated in vitro with 0, 0.01, 0.1, 1, and 10% (w/v) amisulbrom to determine its effect on spore germination and viability. Amisulbrom inhibited resting spore germination by up to 79% and reduced viable spores by 31% relative to the control. Applications of a liquid solution (AL1000, 1000 g active ingredient (ai) ha-1) and granular formulations (AF700, 700 g ai ha-1; AF1000, 1000 g ai ha-1; AF1500, 1500 g ai ha-1) of amisulbrom were tested on the canola cultivars '45H31' (clubroot-susceptible) and 'CS2000' (moderately resistant) under greenhouse conditions and in field experiments in 2019 and 2020. In the greenhouse, the treatments were evaluated at inoculum concentrations of 1 × 105 or 1 × 107 resting spores g-1 soil. A trend of decreasing clubroot severity with an increasing amisulbrom rate was observed. At the lower spore concentration, treatment with AF1500 resulted in a clubroot disease severity index (DSI) <20% for both cultivars, while the lowest DSI under both low and high spore concentrations was obtained with AL1000. The field results indicated a significant reduction in DSI, with varied effects of rates and liquid vs. granular formulations. The greatest reductions (up to 58.3%) in DSI were obtained with AF1500 and AL1000 in 2020. These findings suggest that amisulbrom holds promise as part of an integrated clubroot management approach.

Seasonality and intensity of airborne Boletus-type spores in relation to land use and weather pattern

Forests are a natural source of airborne bolete spores. The timing of sporulation and its intensity as well as the dispersal of airborne spores and in consequence their concentrations depend in particular on the type of land use determining the availability of matter on which they develop and on meteorological factors. The aim of this study was to perform a spatial and temporal analysis of the occurrence of Boletus-type spores in the warm temperate climate of the Northern Hemisphere. An assumption was made that the spore concentrations depend on the type of land cover and weather conditions. The volumetric method was applied to investigate differences in spore concentrations and using spore traps installed at different heights and at locations with different land cover types. Boletus-type spores occurred in the air at high concentrations in late summer and in the autumn. The season start dates and maximum concentrations did not differ significantly between sites and seasons, but the season intensity varied. Higher spore concentrations were usually found in the region with a larger proportion of green areas, including forests. An analysis of the diurnal cycles showed that within 24 h spore concentration reached high levels twice, which was especially noticeable in ground level monitoring. Air temperature and air humidity were the main weather factors affecting the occurrence of airborne spores. This research indicates that when studying the effects of different factors on the concentration of airborne basidiospores, many environmental elements should be analyzed, including the characteristics of habitats in which basidiomycetes grow. Climate, weather, geobotany, and land use type should be taken into account in analysis and interpretation of aeromycological phenomena.

Evaluation of the Influence of Culture Media and Neem Cake Extract on the Growth Rate of Three Soil Borne Fungi (Trichoderma harzianum, Trichoderma viride and Sclerotium rolfsii)

Aims: To evaluate the performance and efficacy of three fungi on pure Sabouraud dextrose agar (SDA), Potato dextrose agar (PDA), malt extract agar (MEA); SDA, PDA and MEA modified in combination with different neem cake concentrations.&#x0D; Study Design: The experiment was laid out in a completely randomized design.&#x0D; Place and Duration of Study: Department of Botany, University of Calabar, between July 2021 and September, 2021.&#x0D; Methodology: Fungal pathogens were isolated from soil samples and infected fruits of water melon. Different culture media were used to grow the pathogens. Chloramphenicol (250mg) was added to each medium, autoclaved at 1210C for 15 minutes, and kept at room temperature of 21 ± 10C. After inoculation, colonies were sub cultured to obtain pure culture. Media modification was achieved by adding 10g, 20g, 30g and 40g of extract. Cork borer (5mm) of fungi stock culture were transferred to Petri dishes. Linear growth of fungi was recorded after 16 hours. Average linear growth rate was measured at 12 hours interval for five days.&#x0D; Results: Spore concentration of Sclerotium rolfsii was significantly higher in pure media than in modified media. Among modified media, concentrations were significantly higher in both PDA and MEA at 1.60x106 spores/ml. Trichoderma viride on pure SDA produced the highest spore concentration at 4.80x106 spores/ml followed by pure PDA at 4.10x106 spores/ml, whereas on the modified media, MEA had the highest spore concentration at 1.80x106 spores/ml. Pure Potato Dextroes Agar (PDA) of Trichoderma harzianum produced the highest spores at 6.10x106 spores/ml while MEA and SDA had close range of spore production at 4.90x106 and 4.30x106 spores/ml respectively. Modified MEA had the highest spore concentration at 1.30x106 spores/ml followed by SDA which had 1.1x106 spores/ml.&#x0D; Conclusion: The mycelia growth rate reveals that both pure and modified MEA supported the growth of all the fungi better than PDA and SDA.

Efficacy of UV and UV-LEDs Irradiation Models for Microbial Inactivation Applicable to Automated Sterile Drug Compounding

LEDs development has attracted attention over conventional mercury lamps for the tiny size, high efficiency, long lifetime, low operating temperature. The antimicrobial effectiveness of traditional UV-lamps radiation (wavelength of 254 nm) compared to UV-C LEDs (LED1 wavelength range 275–286 nm and LED2 range 260–270 nm) was carried out, for possible applications to automated sterile drug compounding. The UV lamp and the tested UV-LED devices remarkably reduced microbial load, following a time-dose response, but the best performance was evidenced by LED1, which guaranteed the complete inactivation of high concentrations of bacteria, yeasts, and spores at doses between 200 and 2000 J/m2.

Vertical spread of Hymenoscyphus fraxineus propagules

Currently, the ash dieback causal agent Hymenoscyphus fraxineus is an established invasive pathogen in most European countries. Its potential to spread quickly among invaded forests is based on its propagules: airborne inoculum composed mainly of ascospores originated in apothecia growing on leaf litter infected during the previous vegetation season. The spread of the inoculum by air masses to distant areas is probable and depends on the availability of the ascospores in higher levels of air. Our study aimed to detect the inoculum in an infected area at heights of more than 20 meters. Our study was conducted in a municipal locality (Boršov nad Vltavou) with tens of infected ash trees (Fraxinus excelsior) in South Bohemia (SW Czechia). The infected trees surround an agricultural silo where five rotating arm spore traps (rotorods) were mounted for ten consequent 48h samplings during the peak of the sporulating season (17th July to 6th August 2020). The spore traps were mounted 48, 37, 25, 14 and 0,3 meters above ground. Samples were quantified by qPCR. Results clearly proved the ability of the spores to reach a height of 48 meters. Furthermore, H. fraxineus DNA was detected from all five spore traps during all ten samplings. Mostly, the amount of detected spores showed a decreasing trend with height, and varied a lot. During some of the samplings, higher spore concetrations were achieved at the top than at the lower traps, which can be explained by horizontal air transfer of the inoculum from other infected areas. Based on GLM analyses, higher spore concentrations were achieved during days without rain, lower air temperatures, after cloudy, humid and rainy weather without strong winds. A combination of rotorod ROTTRAP 52 with qPCR quantification proved to be an efficient technology for a study focused on the vertical spread of H. fraxineus propagules.

Myxozoan fish diseases: possible treatment and zoonoses.

Myxozoan parasites pose huge threat to wild and cultured fishes and reported to cause heavy mortality, retarded growth and post-harvest quality degradation. It is one of the highly divergent groups of parasites which infects skin, gill, muscle, cartilage and internal organs of host fish and the severity of pathology varies depending on the water temperature, species of fish, site of tissue infection and immune resistance of the individual host. Most infections are difficult to treat, as they can easily evade host cellular and humoral defence mechanisms by proliferating or migrating through immune compromised sites of the host and forming large plasmodia encapsulated by the host cellular elements. This spore-forming parasite is harmless to humans but often detected in faecal samples of immunosuppressed humans. The incidences are mostly associated with the consumption of infected fish having a high concentration of spores which causes diarrhea and stomach pain. Currently, there are no immunostimulants or vaccines available for controlling these parasites, however, fumagillin is the drug of choice in fish for controlling this parasitic infection. Excessive usage of fumagillin causes tissue damage and retarded growth in fish, hence feed incorporation of this antibiotic in proper dose is essential for effective treatment. In this review detailed information on the diseases caused by myxozoan parasites in fishes and their zoonotic potential is discussed.

Genome Sequence Resources for Verticillium dahliae-Inhibiting Streptomyces spp. Isolated from Agricultural Soil

Gram-positive Streptomyces bacteria are common in soil, where they can inhibit soilborne plant pathogens by producing antimicrobial secondary metabolites. This study generated genome assemblies of Streptomyces isolates from soil that inhibit the soilborne plant pathogen Verticillium dahliae. Five bacterial isolates were cultured from soil collected from the Salinas Valley region of California. In vitro tests showed that three bacterial isolates inhibited V. dahliae growth when applied at low and high spore concentrations, whereas two isolates only inhibited V. dahliae when applied at high spore concentrations. Generation of hybrid Illumina-Nanopore assemblies showed that isolate genomes ranged from 7.45 to 8.95 Mbs. The contig number per assembly ranged from 1 to 54. All assemblies had 100% completeness values based on a standard set of conserved orthologs found in all bacteria. The number of predicted genes ranged from 6,594 to 8,098. Over 25 putative secondary metabolite biosynthetic clusters were identified in each assembly. Calculation of digital DNA:DNA hybridization and average nucleotide identity values using additional genome assemblies from type specimens of Streptomyces showed that the five isolates are likely novel Streptomyces spp. The results and data generated from this study will provide a basis for future research on the use of Streptomyces for managing common soilborne pathogens such as V. dahliae. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 “No Rights Reserved” license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2023.

A simple and effective aerosol pathogen disinfection test for a flowing air disinfector

Aerosol transmission is an important disease transmission route and has been especially pertinent to hospital and biosafety laboratories during the SARS-CoV-2 pandemic. The thermal resistance of airborne SARS-CoV-2 is lower than that of Bacillus subtilis spores, which are often used to test the effectiveness of SARS-CoV-2 and other pathogen disinfection methods. Herein, we propose a new method to test the disinfection ability of a flowing air disinfector (a digital electromagnetic induction air heater) using B. subtilis spores. The study provides an alternative air disinfection test method. The new test system combined an aerosol generator and a respiratory filter designed in-house and could effectively recover spores on the filter membrane at the air outlet after passing through the flowing air disinfector. The total number of bacterial spores used in the test was within the range of 5 × 105–5 × 106 colony-forming units (CFUs) specified in the technical standard for disinfection. The calculation was based on the calculation method in Air Disinfection Effect Appraisal Test in Technical Standard for Disinfection (2002 Edition). At an air speed of 3.5 m/s, we used a digital electromagnetic induction air heater to disinfect flowing air containing 4.100 × 106 CFUs of B. subtilis spores and determined that the minimum disinfection temperature was 350 °C for a killing rate of 99.99%. At 400 °C, additional experiments using higher spore concentrations (4.700 × 106 ± 1.871 × 105 CFU) and a higher airspeed (4 m/s) showed that the killing rate remained>99.99%. B. subtilis spores, as a biological indicator for testing the efficiency of dry-heat sterilization, were killed by the high temperatures used in this system. The proposed method used to test the flowing air disinfector is simple, stable, and effective. This study provides a reference for the development of test systems that can assess the disinfection ability of flowing air disinfectors.

High concentration of spores and colony forming units of the biocontrol agent Beauveria bassiana via optimization of submerged cultivation

Liquid cultivation for the production of mycoinsecticides has received recent attention by the industry, due to the many advantages over the solid-state cultivation process. However, important variables must be considered to enable the production of the fungus propagules in the liquid medium. In this study, the optimization of the culture medium and the influence of pH and dissolved oxygen (DO) parameters on the production of spores of Beauveria bassiana in liquid process was investigated. The strain of B. bassiana IBCB 868 was growth in shake flasks followed by experimental design to find the optimal medium condition for spores production. Optimization of the culture medium was performed using a Plackett-Burman design followed by a central composite rotational design (CCRD). The optimized conditions resulted in high concentrations of submerged spores (2.21 × 109 SS mL−1) and colony forming units (1.52 × 109 CFU mL−1) on the third day of cultivation. There was an increase of 165.05% and 210.16% in SS and CFU production, respectively, in the optimized condition when compared to the most favorable culture medium initially tested. Benchtop bioreactor assays with the optimized medium were performed and the influence of pH and DO was investigated. It was observed that the pH fixed at 4.5 and 10% DO in 24 h, followed by 50% DO until 48 h and 30% DO until the end of the cultivation provided the highest concentrations of SS (1.98 × 109 SS mL−1) and CFU (1.9 × 109 CFU mL−1) after four days of growth.

Микологические факторы риска развития респираторных аллергозов тяжелого течения у населения, проживающего на юге России

Aim: to determine the concentration of mold spores and causative allergens of pollen-producing grasses in the cities of Southern Russia and to assess the prevalence of multisensitization in patients with severe allergic respiratory diseases, taking into consideration mold specific IgE results. Patients and Methods: from 2018 to 2020, concentrations of airborne allergens were evaluated in Stavropol, Krasnodar and Rostov-on-Don according to international techniques, using Burkard and Lanzoni volumetric spore and pollen traps. The levels of non-bacterial allergen- specific IgE were evaluated by allergen component testing in 143 patients (69 children and 74 adults) with allergic rhinitis and atopic asthma. Results: the results of aeropalynology studies demonstrated a high concentration of mold spores in the atmospheric air of all the studied cities co-occurring with seasonal increases in pollen allergen concentrations in the atmospheric air. The South of Russia is characterized by the year-round presence of mold allergens with sporulation peaks in July, August and September. The peak utilization of healthcare services coincided with the maximal concentration of plant pollen and mold spores. The results of comprehensive allergy diagnostic testing suggest that there is a predominance of patients with multisensitization (71%), including sensitization to pollen and mold spore allergens. As a result of the overlapping of the peaks of spreading airborne pollen allergens and mold sporulation, a frequent use of short-acting emergency β2-agonists and more calls for ambulance service are reported. Conclusion: the predominance of patients with multisensitization leads to the development of severe allergic respiratory diseases. Measures of timely management and prevention are needed for such patients. A daily monitoring of sporulation levels and pollen allergens in the air may help to avoid contacts with high concentrations of causative allergens and to implement the necessary preventive measures. The annual aeropalynology monitoring will provide an opportunity to predict allergen concentrations in the atmospheric air during the current year and to develop a statistically significant monitoring model in the future. KEYWORDS: molds, ragweed, aeromycology, aeropalynology, allergens, allergen component testing. FOR CITATION: Ukhanova O.P., Bogomolova E.V., Budnikov P.V. et al. Mycotic risk factors for the development of severe respiratory allergosis in the population of southern Russia. Russian Medical Inquiry. 2023;7(2):65–74 (in Russ.). DOI: 10.32364/2587-6821-2023-7-2-65-74.

Weapons against Themselves: Identification and Use of Quorum Sensing Volatile Molecules to Control Plant Pathogenic Fungi Growth.

Quorum sensing (QS) is often defined as a mechanism of microbial communication that can regulate microbial behaviors in accordance with population density. Much is known about QS mechanisms in bacteria, but fungal QS research is still in its infancy. In this study, the molecules constituting the volatolomes of the plant pathogenic fungi Fusarium culmorum and Cochliobolus sativus have been identified during culture conditions involving low and high spore concentrations, with the high concentration imitating overpopulation conditions (for QS stimulation). We determined that volatolomes emitted by these species in conditions of overpopulation have a negative impact on their mycelial growth, with some of the emitted molecules possibly acting as QSM. Candidate VOCs related to QS have then been identified by testing the effect of individual volatile organic compounds (VOCs) on mycelial growth of their emitting species. The antifungal effect observed for the volatolome of F. culmorum in the overpopulation condition could be attributed to ethyl acetate, 2-methylpropan-1-ol, 3-methylbutyl ethanoate, 3-methylbutan-1-ol, and pentan-1-ol, while it could be attributed to longifolene, 3-methylbutan-1-ol, 2-methylpropan-1-ol, and ethyl acetate for C. sativus in the overpopulation condition. This work could pave the way to a sustainable alternative to chemical fungicides.

Indoor air quality and early detection of mould growth in residential buildings: a case study.

Mould growth affects one in three homes, and it is the biggest cause for complaints and litigations filed to the relevant authorities in Australia, while also significantly affecting the physical and psychological health of the building's occupants. Indoor mould is caused by excessive dampness, resulting from poor architectural specification, construction and maintenance practices, as well as inappropriate behaviour of the occupants. The consequences range from early biodeterioration of building materials, requiring anticipated renovation works, to deterioration of the indoor environment, posing a serious threat to the building's occupants. This study investigates indoor air quality (IAQ) and mould growth, providing a snapshot of the current IAQ of Australian residential buildings regarding air pollutants. It uses a case study representative of the typical Australian suburban home to investigate the effects of unnoticed mould growth. The results of the monitoring campaign indicate that buildings with a high concentration of fungal spores are also more likely to present poor IAQ levels, high concentrations of particulate matters (PM10 and PM2.5) and carbon dioxide (CO2). This research suggests the need for the development of early detection strategies that could minimise the health hazard to people, thereby preventing the need for any major renovations.

Three-year pollen and fungi calendar in a Mediterranean region of the Northeast Greece.

Pollen calendars have been proved clinically important in allergic disease management, as differences in airborne allergens exist not only between different countries but also between regions of the same country as well. This study aims to provide new data regarding the atmospheric pollen and fungi content of a Mediterranean region (Western Thrace/North-East Greece) and discuss seasonal trends, differences in pollen grains and fungi spores' circulation over the years, and correlations with climate parameters. A 7-day continuously running volumetric trap was used to collect circulating pollen grains and fungi spores. Pollen taxa and fungi were characterized by standard protocols and counted as grains /m3 and average total grains and spores. The primary allergenic pollen season was discovered, and their 10-day averages were measured over time. Correlations with temperature, rain, and humidity were assessed by single linear regression analysis. Pollen grains from nine pollen families were identified, including five arboreal, two nonarboreal taxa, and spores from two fungi species. The three most prevalent taxa were Oleaceae, Poaceae, Pinaceae, and Cladosporium in the fungi. Peak pollen concentrations were detected during April and May, with daily averages exceeding 170 grains/m3. Poaceae presented the longest pollen season of 342 days and Oleaceae the shortest, extending to only 110 days, during the 3years. Cladosporium was the fungus with the highest spore concentration (180,129.9 spores) compared with Alternaria (28,026.1 spores). Correlations with meteorological parameters showed variable associations among different taxa, with rainfall and relative humidity being the most significant determinants. In this study, the pollenic and fungal spectrum of a Mediterranean region and information that can be proved clinically significant for the appropriate diagnostic and therapeutic approach of allergic patients was presented.

First Report of Leaf Spot Disease on Microstegium vimineum Caused by Bipolaris setariae in China.

First Report of Leaf Spot Disease on Microstegium vimineum Caused by Bipolaris setariae in China.

Sedimentary Environmental Evolution of the Western Taiwan Shoal Area since the Late Pleistocene

A new pollen analysis and major and trace element contents were conducted on a 40 m long gravity core recovered from the Taiwan Shoal (sand ridges), south of the Taiwan Strait, beginning in the Late Pleistocene. The changes in the pollen assemblage and concentration represent the climate change around the Taiwan Shoal and the strength of the Zhe-Min Coastal Current, whereas variations in major and trace element contents can imply the source of the sediments in the Taiwan Shoal, which are correlated with the rise or fall of the sea level with increased marine dinoflagellate cysts. The interval of 40–30 m was characterized by high pollen and spore concentrations, and evergreen Quercus was dominant taxon, which indicates a warm sedimentary environment, and the surrounding area of the Taiwan Shoal were covered by a tropical and subtropical broad-leaved forest. There were no pollen and spores from 30–24 m, which indicates a strong hydrodynamic sedimentary environment, and most of the Taiwan Shoal might have been experience subaerial exposure. The interval of 24–17 m was characterized by the reappearance of pollen and spores, as well as marine dinoflagellate cysts and foraminifera, suggesting the climate was warm and wet in the study area and an apparent marine sedimentary environment with relatively high sea level. Deciduous Quercus dominated the interval of 17–12 m, which indicated that the climate was relatively cool, corresponding to the end of Marine isotope stages3 (MIS3) to the Last Glacial Maximum accompanied by weathering and denudation. Above 12 m, the low pollen concentration with increased marine dinoflagellate cysts and foraminifera abundance suggested a marine sedimentary environment in the Taiwan Shoal. The high concentrations in Pinus corresponds to Holocene high sea level.

Submerged Bioreactor Production of Geobacillus stearothermophilus ATCC 7953 Spores for Use as Bioindicators to Validate Hydrogen Peroxide Inactivation Processes

In the food and pharmaceutical industries, evaluating the sterilization performance preceding aseptic production processes is of central importance. In the case of hydrogen peroxide sterilization of solid surfaces, bioindicators (BI) consisting of spores of Bacillus atrophaeus or Geobacillus stearothermophilus are used to validate the effectiveness and efficiency of the inactivation procedure. Commercial production of G. stearothermophilus is commonly performed on agar plates, where cultivation and sporulation conditions are not well-defined. Therefore, the produced BI can vary in their resistance, which in turn creates unacceptable uncertainties in the evaluation of aseptic processes. Submerged production in the bioreactor would allow more control over sporulation conditions, while reducing production time, resistance variability, and avoidance of false-positive or false-negative test results. In addition, submerged production of G. stearothermophilus so far was a challenge to achieve sufficiently high spore concentrations for BI production. This study reports on the development of a method for submerged production of G. stearothermophilus spores (pH 7.0, 57 °C, 30% pO2) that can achieve 1.6 × 107 spores/mL with a resistance against 35% H2O2 at 25 °C of D25°C,35% H2O2 = 73 s. This resistance ranks within the range of commercially available BI, making the results directly transferable to industrial applications.