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The aerial surface of plants, known as the phyllosphere, represents a widespread and diverse habitat for microbes, but the fungal communities colonizing the surface of leaves are not well characterized, and how these communities are assembled on hosts is unknown. We used high-throughput sequencing of fungal communities on the leaves of 51 tree species in a lowland tropical rainforest in Panama to examine the influence of host plant taxonomy and traits on the fungi colonizing the phyllosphere. Fungal communities on leaves were dominated by the phyla Ascomycota (79% of all sequences), Basidiomycota (11%), and Chytridiomycota (5%). Host plant taxonomic identity explained more than half of the variation in fungal community composition across trees, and numerous host functional traits related to leaf morphology, leaf chemistry, and plant growth and mortality were significantly associated with fungal community structure. Differences in fungal biodiversity among hosts suggest that individual tree species support unique fungal communities and that diverse tropical forests also support a large number of fungal species. Similarities between phyllosphere and decomposer communities suggest that fungi inhabiting living leaves may have significant roles in ecosystem functioning in tropical forests. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Résumé: Des grains millimétriques d’ambre sont associés à des débris ligniteux dans la série marine du Santonien de Belcodène (Bouches-du-Rhône, France). Il s’agit surtout de grains en forme de goutte, jaunes à rougeâtres, plus ou moins transparents. Ils révèlent la présence de divers microorganismes appartenant à des procaryotes (bactéries, actinomycètes) ou des eucaryotes (champignons) décrits ici pour la première fois. Ces microorganismes constituent parfois des croûtes à la périphérie des grains d’ambre et se sont développés de manière centripète dans la résine encore fluide. Le milieu de dépôt de l’ambre était ouvert sur des influences marines, tandis que le milieu de formation des coulées de résine était une forêt côtière constituée essentiellement d’angiospermes. [ABSTRACT FROM AUTHOR]

Copyright of VertigO is the property of La Revue Electronique en Sciences de l'Environnement VertigO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ethnobotany of Latin-American native people always surprised us with the forms of order, name and use plants. This article shows us how an Amazonian Indian society, the aguaruna, belonging to the Jibaro ethnolinguistic group, classified fungi in the rainforest. The two basic criteria that are used: edible and non-edible. [ABSTRACT FROM AUTHOR]

Humicola lutea 103 is a copper-tolerant fungal strain able to grow in the presence of 300 μg·mL-1 Cu2+ under submerged cultivation. To prevent the consequences of copper overload, microorganisms have evolved molecular mechanisms that regulate its uptake, intracellular traffic, storage, and efflux. In spite of this avoidance strategy, high heavy-metal concentrations caused distinct and widespread ultrastructural alterations in H. lutea. The mitochondria were the first and main target of the toxic action. The effect of copper on activities of the key enzymes (hexokinase, glucose-6-phosphate dehydrogenase, malate dehydrogenase, and isocitrate dehydrogenase) included in the 3 main metabolic pathways, glycolysis, pentose phosphate pathway, and tricarboxylic acid cycle, was investigated. High metal concentrations exhibited a dramatic negative effect on hexokinase, while the other 3 enzymes showed a significant and dose-dependent stimulation. On the basis of the present and previous results we concluded that the copper-induced oxidative stress plays an important role in the fungal tolerance to high Cu 2+ concentrations. [ABSTRACT FROM AUTHOR]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A common problem when growing Sphagnum mosses in the greenhouse is the propagation of parasitic fungi. Since no clear procedure is available to correct the situation, the aim of this experiment is to give scientists and growers a tool to control fungi invasions in the greenhouse. First, eight fungicides and the effect of temperature were tested on Petri dishes inoculated with two fungi commonly found in Sphagnum: Lyophyllum palustre (Peck) Singer and Chaetomium sp. To assess Sphagnum tolerance to fungicides, the four most efficient treatments were tested on healthy Sphagnum carpet, at maximum and minimum concentrations. Finally, the most promising fungicide, Nova (myclobutanil), was tested on Sphagnum carpets infected by L. palustre and Chaetomium sp. Since the concentration of this fungicide had no effect on biomass accumulation, the maximum concentration (0.54 g/L) was tested. Because of the high absorbency of Sphagnum, Nova was applied at the recommended dose (1 L/10 m2) and at three times the recommended dose (3 L/10 m2). An evaluation of infected Sphagnum individuals was carried out after a frequency of two and three applications. The recommendation for controlling the invasion of Sphagnum by L. palustre and Chaetomium sp. in the greenhouse is the application of Nova fungicide at three times the recommended dose. The frequency of applications had no significant effect. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the occurrence of fungi in aerobic and anoxic activated sludge from membrane bioreactors. Thirty-six samples from each aerobic and anoxic activated sludge were taken from two membrane bioreactors treating domestic wastewater. Over a period of 9 months, four samples from each plant were taken per month. The samples were prepared for count and identification of fungi. Sixty species belonging to 30 genera were collected from activated sludge samples under aerobic and anoxic conditions. In terms of fungal identification, under aerobic conditions was found at 94.4% followed by species at 80.6%, yeasts at 75.0%, and species at 50.0%; under anoxic conditions G. candidum at 86.1%, yeasts at 66.6%, and Penicillium species at 61.1% were the most prevalent. The results indicate that activated sludge is a habitat for growth and sporulation of different groups of fungi, both saprophytic and pathogenic. [ABSTRACT FROM AUTHOR]

Abstract: The relationship between biodiversity and biogeochemical processes gained much interest in light of the rapidly decreasing biodiversity worldwide. In this article, we discuss the current status, challenges and prospects of functional concepts to plant litter diversity and microbial decomposer diversity. We also evaluate whether these concepts permit a better understanding of how biodiversity is linked to litter decomposition as a key ecosystem process influencing carbon and nutrient cycles. Based on a literature survey, we show that plant litter and microbial diversity matters for decomposition, but that considering numbers of taxonomic units appears overall as little relevant and less useful than functional diversity. However, despite easily available functional litter traits and the well-established theoretical framework for functional litter diversity, the impact of functional litter diversity on decomposition is not yet well enough explored. Defining functional diversity of microorganisms remains one of the biggest challenges for functional approaches to microbial diversity. Recent developments in microarray and metagenomics technology offer promising possibilities in the assessment of the functional structure of microbial communities. This might allow significant progress in measuring functional microbial diversity and ultimately in our ability to predict consequences of biodiversity loss in the decomposer system for biogeochemical processes. [Copyright &y& Elsevier]

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mathematical modeling in the biofiltration of volatile organic compounds is a valuable tool for performance prediction and in scaling up. Majority of the published models include parameters obtained from fitting experimental data, thus masking their real influence as they are lumped generally. The present work aims to evaluate experimentally some of the most relevant parameters including kinetic constant, partition coefficient in the biofilm, biofilm thickness, superficial area, and effective diffusivity. For the fungal biofilm, all the parameters mentioned above were obtained experimentally; and for the bacterial biofilm, the biofilm thickness and some intrinsic parameters used to obtain the first-order kinetic constant were taken from the literature. These parameters were then incorporated in a mathematical model to describe the steady-state degradation of hexane in bacterial and fungal biofilters operating under continuous mode. Experimentally, the dimensionless partition coefficients (mG) indicated that hexane was 4 and 35 times more soluble in the bacterial (mG = 9.14) and fungal (mG = 0.88) biofilters, respectively, than in water (mG = 30.4). Comparison of model estimates with experimental concentration profiles of the pollutant along the height of the biofilters proves that the first-order limited by reaction model was appropriate to interpret the experimental results with a small error of ~1%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cryptogamie Mycologie is the property of Museum National d'Histoire Naturelle, Paris and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents a study which examines the genetic aspects of 15-acetyldeoxynivalenol (15-ADON) chemotypes of Fusarium graminearum fungal population in Canada. The study employs restriction length fragment polymorphism, in which 206 monoconidial isolates of F. graminearum's chemotype were selected for genetic analysis based on their mycotoxin. Results reveal a genetic homogeneity among the F. graminearum population which suggests the chemotypes' geographic population expansion in Canada.

Abstract: Some intoxications are more specifically linked to the Aquitaine region than to other regions of France, due to environmental circumstances (fauna, flora, climate) or traditional activities (gastronomy). Three types of intoxications are particular in this area. Pine processionary caterpillar envenomations (Thaumetopoea pityocampa), a Southern Europe pinewood parasite, are frequently encountered in the Landes’ forest. They are responsible of ocular and/or skin lesions with urticaria or contact dermatitis, seldom associated with immediate IgE hypersensitivity. According to the south Atlantic coastal region geology and the marine streams, venomous marine animals are mainly located in Charente-Maritime for jellyfish, in Gironde and in Landes for weeverfish and in Atlantic Pyrenees for sea anemone. Usually not dangerous, first-aid workers treat most cases of these envenomations. Some endemic mushrooms (Tricholoma auratum) which grow on the dunes of the Atlantic coastal region, are usually considered as very good comestibles, but were recently responsible for serious intoxications: T.auratum was responsible of several cases of rhabdomyolysis, without neurological involvement, nor renal or hepatic lesion. Three deaths were notified. Animal studies confirmed the responsibility of the mushrooms. [Copyright &y& Elsevier]

Copyright of Phytothérapie is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Composting is a microbial process that converts organic waste into a nutrient-rich end product used in horticultural and agricultural applications. The diversity and long-term succession of microorganisms found in composted biosolids has been less characterized than other composts. In this study, bacterial and fungal communities found in composted biosolids aging from 1 to 24 months were studied using denaturing gradient gel electrophoresis (DGGE) and sequencing. The results revealed high levels of diversity, where 53 bacterial species belonging to 10 phyla and 21 fungal species belonging to 4 phyla were identified. Significant differences were observed when comparing the bacterial DGGE patterns of young compost samples, whereas no differences were observed in samples over 8 months. For fungal patterns, no significant differences were observed during the first 4 months of composting, but the diversity then significantly shifted until 24 months. The results indicate that patterns of bacterial species vary during the first few months of composting, whereas fungal patterns generally vary throughout the whole process, except during early stages. The description of the main microbial groups found in composted biosolids could find various applications, including the discovery of biotechnologically relevant microorganisms and the development of novel markers allowing quantitative monitoring of key microorganisms. [ABSTRACT FROM AUTHOR]

Copyright of Cryptogamie Mycologie is the property of Museum National d'Histoire Naturelle, Paris and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Materials & Structures is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Phytothérapie is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the impacts of soil fungi on seeds of two eastern North American temperate-zone trees: Acer saccharum Marsh. (sugar maple) and Tsuga canadensis (L.) Carr (eastern hemlock). Seeds of each species were buried at locations dominated by either conspecifics or heterospecifics. Half were protected with fungicide, and the net consequences for survival and germination were assessed. Net effects of fungicide usually were positive, indicating that pathogens affected seeds more strongly than any potential mutualists. Losses of A. saccharum to fungi were modest, and almost identical in areas dominated by itself versus areas dominated by T. canadensis. In contrast, fungal impacts on T. canadensis were strongly habitat-dependent: losses to fungi were high in T. canadensis-dominated sites, but not in A. saccharum-dominated sites. This result is consistent with an accumulation of host-specific pathogens, either by a direct feedback between T. canadensis and its fungal enemies, or indirectly through modification of the soil environment. Even though these two trees share similar habitats, responses to fungicide indicate that their seeds are affected very differently by the soil environment. [ABSTRACT FROM AUTHOR]

Twenty-two fungi were studied to determine the potential for development of fungal nitrogen treatment (FNT) technology for municipal wastewater. Fungal nitrogen treatment has been hypothesized to have several significant advantages over bacterial nitrification–denitrification systems. The fungi were isolated from the biological nutrient reactor at the Gold Bar Wastewater Treatment Plant in Edmonton, Alberta, Canada. Fungi were screen for nitrogen treatment potential using an aerobic 3 day ammonium concentration decrease test. Seven fungi were found to have potential for nitrogen or phosphorus treatment. The highest average ammonium decreased was 59% with an average initial concentration of 22 mg N L–1. Fungal nitrogen treatment was also characterized by a lack of production of nitrate or nitrite under aerobic conditions. Data analysis indicated, the ammonium decrease was not consistent with nitrogen assimilation. [ABSTRACT FROM AUTHOR]

Using an approach based on polymerase chain reaction (PCR), we examined the diversity of polyketide synthase (PKS) genes present in 160 marine fungal isolates, representing 142 species. We obtained ketosynthase (KS) domain PCR products from 99 fungal isolates, representing Dothideomycetes, Sordariomycetes, Eurotiomycetes, and incertae sedis. Sequence similarity searches and phylogenetic analysis of 29 marine partial-KS-encoding sequences revealed domains predicted to encode reducing, nonreducing, and 6-methylsalicylic acid PKSs. Bioinformatic analysis of an alignment of the KS sequences from marine-derived fungi revealed no unique motifs in this region. However, several specificity-determining positions were apparent between fungal 6-methylsalicylic acid PKSs as compared with either reducing or nonreducing PKSs. Evaluation of these positions in the context of a modelled three-dimensional protein structure highlighted their potential use as PKS classification markers. Evaluating primer-binding sites was necessary to obtain KS domain fragments from putative PKSs while maintaining a level of sequence information adequate to properly classify and characterize them. [ABSTRACT FROM AUTHOR]

The Wallemiomycetes includes three species of molds from the genus Wallemia. These fungi are adapted to environments of high osmotic stress, contaminate various foods, cause respiratory disease, and have an unusual mode of asexual reproduction. Wallemia was recently proposed as a new class based on 18S ribosomal RNA gene sequences to accommodate the isolated position of the clade in the Basidiomycota. We analyzed the phylogenetic position of the Wallemiomycetes using 3451 nucleotide characters of the 18S, 25S, and 5.8S ribosomal RNA genes and 1282 amino acid positions of rpb1, rpb2, and tef1 nuclear protein-coding genes across 91 taxa. Different gene regions and methods of phylogenetic inference produce mildly conflicting placements of the Wallemiomycetes. Parsimony analyses of nrDNA data suggest that the Wallemiomycetes is an early diverging lineage of Basidiomycota, occupying a basal position near the Entorrhizomycetidae. Ultrastructural data, some Bayesian analyses, and amino acid sequences suggest the Wallemiomycetes may be the sister group of the Agaricomycotina or Ustilaginomycotina. The combined gene tree supports the Wallemiomycetes as a lineage basal to a core clade of Pucciniomycotina, Ustilaginomycotina, and Agaricomycotina with robust measures of branch support. This study reinforces the isolated position of Wallemia in the Basidiomycota using molecular data from six nuclear genes. In total, five major lineages of Basidiomycota are recognized: the Agaricomycotina, Ustilaginomycotina, Pucciniomycotina, Entorrhizomycetidae, and the Wallemiomycetes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The competitor fungus Trichoderma aggressivum causes green mould disease, a potentially devastating problem of the commercial mushroom Agaricus bisporus. Due to the recent appearance of this problem, very little is known about the mechanisms by which T. aggressivum interacts with and inhibits A. bisporus. A mechanism generally used by Trichoderma species in the antagonism of other fungi is the secretion of cell wall degrading enzymes. In this study, we determined the activities of chitinases produced in dual cultures of these fungi over a 2 week period. Both intracellular and extracellular enzymes were studied. Agaricus bisporus produced N-acetylglucosaminidases with apparent molecular masses of 111, 105, and 96 kDa. Two resistant brown strains produced greater activities of the 96 kDa N-acetylglucosaminidase than susceptible off-white and white strains. This result suggested that this enzyme might have a role in the resistance of commercial brown strains to green mould disease. Trichoderma aggressivum produced three N-acetylglucosaminidases with apparent molecular masses of 131, 125, and 122 kDa, a 40 kDa chitobiosidase, and a 36 kDa endochitinase. The 122 kDa N-acetylglucosaminidase showed the greatest activity and may be an important predictor of antifungal activity. [ABSTRACT FROM AUTHOR]

Flower heads of economically important members of the genus Protea L. mature into conspicuous, often long-lived infructescences, which in South Africa are commonly colonized by species of the ophiostomatoid fungi Gondwanamyces G.J. Marais & M.J. Wingfield and Ophiostoma Syd. & P. Syd. It is suspected that these fungi are transported between infructescences by insects. To develop techniques that would enable detection of ophiostomatoid fungi on insects, primers GPR1 and OSP1 were designed based on unique 28S ribosomal DNA sequences of Gondwanamyces and Ophiostoma from Protea. Multiplex polymerase chain reaction of these primers, combined with universal primer LR6, yielded fragment lengths of 885 and 637 bp. Positive amplification was achieved from as little as 30 and 45 pg of fungal genomic DNA for Gondwanamyces and Ophiostoma, respectively, and fragments of identical lengths were amplified from insects artificially inoculated with these fungi. No other tested fungal species showed amplification with GPR1 or OSP1 and LR6. Using these primers two insect species (Genuchus hottentottus Fabricius and Oxycarenus maculates Stal.) collected from Protea repens L. infructescences were confirmed as carriers of Gondwanamyces proteae (M.J. Wingfield et al.) G.J. Marais & M.J. Wingfield and Ophiostoma splendens G.J. Marais & M.J. Wingfield, respectively. The method developed in this study represents a rapid detection system that can be used to understand the relationship between insects and ophiostomatoid fungi found associated with flowers of South African species of Protea. [ABSTRACT FROM AUTHOR]

Dampness, moisture, and mold in buildings are associated with adverse health outcomes. In addition to fungi and bacteria, amoebae have been found in moisture-damaged building materials. Amoebae and a growing list of bacteria have been shown to have mutual effects on each other's growth, but the interactions between amoebae and microbes common in moisture-damaged buildings have not been reported. We co-cultivated the amoeba Acanthamoeba polyphaga with bacteria and fungi isolated from moisture-damaged buildings in laboratory conditions for up to 28 days. The microbes selected were the bacteria Streptomycescalifornicus, Bacillus cereus, and Pseudomonasfluorescens, and the fungi Stachybotrys chartarum, Aspergillus versicolor, and Penicillium spinulosum. Fungi and bacteria generally benefited from the presence of the amoebae, whereas the growth of amoebae was hindered by Streptomyces californicus, Stachybotrys chartarum, and Bacillus cereus. Pseudomonas fluorescens slightly enhanced amoebae viability. Amoebae were indifferent to the presence of Aspergillus versicolor and Penicillium spinulosum. Thus, our results show that amoebae can alter the survival and growth of some microbes in moisture-damaged buildings. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aerosolized disinfectant use has appealing qualities for inactivation and remediation of biologically contaminated materials. Their ability to reach exterior and interior spaces of walls and difficult to access areas has potential as a simple and cost effective remediation technique. Stachybotrys chartarum was used as a test organism against four disinfectants: chlorine dioxide, sodium hypochlorite, thiabendazole, and cupric sulfate – sodium hydroxide solution. Tests were conducted independently. The organism was exposed for 4 and 8 h periods to the aerosolized disinfectant. The building material was commercially available gypsum board with paper facing. This material was inoculated under sterile conditions. The commercially available treatments were administered as aerosols generated from a collison nebulizer directed into a sterile growth chamber housing inoculated gypsum board. Surface samples were collected before and after exposures to determine treatment effects. The aerosolized chlorine dioxide and sodium hypochlorite treatments successfully inactivated the organism after 8 h of continuous exposure. [ABSTRACT FROM AUTHOR]

The ultraviolet germicidal irradiation (UVGI) dose necessary to inactivate fungal spores on an agar surface and the efficacy of UVGI were determined for cultures of Stachybotrys chartarum (ATCC 208877). This study employed a UVGI testing unit consisting of four chambers with a 9-W, Phillips, low pressure, mercury UVGI lamp in each chamber. The testing unit's apertures were adjusted to provide 50, 100, 150, and 200 µW/cm2 of uniform flux to the Petri dish surfaces, resulting in a total UVGI surface dose ranging from 12 to 144 mJ/cm2. The UVGI dose necessary to inactivate 90% of the S. chartarum was greater than the maximum dose of 144 mJ/cm2 evaluated in this study. While UVGI has been used to inactivate several strains of culturable fungal spores, S. chartarum was not susceptible to an appropriate dose of UVGI. The results of this study may not correlate directly to the effect of UVGI on airborne fungal spores. However, they indicate that current technology may not be efficacious as a supplement to ventilation unless it can provide higher doses of UVGI to kill spores, such as S. chartarum, traveling through the irradiated zone. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A wide range of ascomycetous microfungi inhabits roots without forming the anatomical features typical of mycorrhizas or causing overt signs of pathogenesis. The most-studied taxa have darkly pigmented hyphal walls and are referred to as "dark septate endophytes" (DSE). We provide a dichotomous key and annotated descriptions for a cross-section of the most common dark septate endophytes. The term DSE is sometimes used to imply taxonomic and physiological similarity even though a diverse range of root endophytic taxa form pigmented hyphae. Among these, Phialocephala fortinii Wang & Wilcox is a well-known representative; it is widespread, easily observed in roots, and readily grown in culture and with plants. Nevertheless, the basis of its symbiotic relationship with plants remains ambiguous. It may be a weak pathogen, a saprotroph on senescent root tissues, or a mutualist. More detailed studies of interactions between identified taxa of microfungal endophytes and host plants are necessary to elucidate the functional basis of these symbioses; it may be necessary to look beyond the paradigms of traditional mycorrhizal and pathogenic associations to understand the ecological roles of these fungi. Reports of cryptic speciation in Phialocephala fortinii emphasize the need for accurate identification of isolates of microfungal endophytes used in experiments. [ABSTRACT FROM AUTHOR]

Increased decomposition rates in boreal peatlands with global warming might increase the release of atmospheric greenhouse gases, thereby producing a positive feedback to global warming. How temperature influences microbial decomposers is unclear. We measured in vitro rates of decomposition of senesced sedge leaves and rhizomes (Carex aquatilis), from a fen, and peat moss (Sphagnum fuscum), from a bog, at 14 and 20 °C by the three most frequently isolated fungi and bacteria from these materials. Decomposition rates of the bog litter decreased (5- to 17-fold) with elevated temperatures, and decomposition of the sedge litters was either enhanced (2- to 30-fold) or remained unaffected by elevated temperatures. The increased temperature regime always favoured fungal over bacterial decomposition rates (2- to 3-fold), Different physiological characteristics of these microbes suggest that fungi using polyphenolic polymers as a carbon source cause greater mass losses of these litters. Litter quality exerted a stronger influence on decomposition at elevated temperatures, as Utter rich in nutrients decomposed more quickly than litter poorer in nutrients at higher temperatures (8.0%-25,7% for the sedge litters vs, 0,2% for the bryophyte litter). We conclude that not all peatlands may provide a positive feedback to global warming. Cautious extrapolation of our data to the ecosystem level suggests that decomposition rates in fens may increase and those in bogs may decrease under a global warming scenario. [ABSTRACT FROM AUTHOR]

Plant-associated microbial diversity encompasses symbionts, protecting their host against various aggressions. Mycorrhizal and rhizospheric microorganisms buffer effects of soil toxic compounds and soil-borne pathogens. Endophytic bacteria and fungi, some of which are vertically inherited through seeds, take part in plant protection by acting directly on aggressive factors (mainly pathogens and herbivores) or by enhancing plant responses. Plant protective microbial symbionts determine the ecological success of plants; they drastically modify plant communities and related trophic webs. This review suggests approaches to improve the inventory of diversity and functions of in situ plant-associated microorganisms. To cite this article: M.-A. Selosse et al., C. R. Biologies 327 (2004). [Copyright &y& Elsevier]

The fastidious nature of nitrifying bacteria has caused many operational problems for wastewater treatment plants employing some form of biological nutrient removal. Research in the field has focused solely on meeting the requirements of this group of bacteria. Recently fungi have been recognized to perform denitrification at greater rates than bacteria. Combining fungi nitrification ability and resistance to inhibitory chemicals, there is the potential for development of a new fungi based biological nitrogen removal system. From the data reviewed, the system would have several significant advantages over conventional biological nutrient removal systems. This paper reviews the ability of fungi to carry out biological nitrogen removal and the potential performance of a fungi based system. Key words: fungi, biological nutrient removal, nitrification, denitrification, membrane bioreactor.La nature exigeante des bactéries nitrifiantes a généré plusieurs problèmes opérationnels aux stations d'épuration des eaux usées utilisant une forme quelconque d'élimination biologique des nutriments. La recherche dans ce domaine s'est concentrée uniquement à rencontrer les exigences de ce groupe de bactéries. Il a été récemment découvert que les champignons pouvaient effectuer la dénitrification à des taux supérieurs à ceux des bactéries. En combinant la capacité de nitrification des champignons et la résistance aux produits chimiques inhibiteurs, il existe un potentiel de développement d'un nouveau système d'élimination biologique des nutriments par champignons. Selon les données examinées, le système comporterait plusieurs avantages importants par rapport aux systèmes conventionnels d'élimination biologique des nutriments. Cet article examine la capacité des champignons à effectuer la dénitrification biologique et le rendement potentiel d'un système basé sur des champignons. Mots clés : champignons, élimination biologique des nutriments, nitrification, dénitrification, bioréacteur à membrane.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]