Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FUNGI”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,801 records · Page 100Linked to original sources
PubMed2002

Soil persistence and biodiversity of ericoid mycorrhizal fungi in the absence of the host plant in a Mediterranean ecosystem.

The occurrence of suitable mycorrhizal inocula may be an important factor affecting the dynamics of plant communities. We investigated the persistence and diversity of ericoid mycorrhizal fungi in the soil of a mature Quercus ilex forest where ericaceous hosts were absent. Erica arborea was used as a bait plant and results were compared to soil samples from experimental plots where cuttings had allowed reappearance of this ericaceous species. Fungal endophytes were isolated and tested in mycorrhiza resynthesis trials. Sterile mycorrhizal endophytes were assigned to morphotypes whose consistency was confirmed by ITS-RFLP. The ITS region of a representative of each morphotype was sequenced. BLAST searches and Neighbour-Joining analysis indicated taxonomic affinities with different classes within Ascomycota. Our results indicate that ericoid mycorrhizal fungi persist and maintain mycorrhizal ability in habitats lacking the ericaceous host. Their persistence could favour the establishment of E. arborea seedlings in pure Q. ilex forests after disturbance phenomena.

Asteraceae↗
PubMed2003

Detoxification of ferulic acid by ectomycorrhizal fungi.

The ectomycorrhizal fungi Laccaria amethystina and Lactarius deterrimus grown in liquid culture were used to study the fate of added ferulic acid. Laccaria amethystina degraded ferulic acid to the major metabolite vanillic acid. The intermediate vanillin was not detected. Lactarius deterrimus showed a completely different detoxification pattern. Two dimers and one trimer of ferulic acid could be identified as polymerization products of this fungus. A bioassay of the possible biological activities of ferulic acid and vanillic acid on these fungi revealed that vanillic acid was less toxic than ferulic acid for Laccaria amethystina but that both phenolic acids were toxic for Lactarius deterrimus. The results are discussed with respect to ectomycorrhizal fungal growth in the organic layer of forest soils and between living root cells of ectomycorrhizas.

Agaricales↗
PubMed2004

Seasonal variation of arbuscular mycorrhizal fungi in temperate grasslands along a wide hydrologic gradient.

We studied seasonal variation in population attributes of arbuscular mycorrhizal (AM) fungi over 2 years in four sites of temperate grasslands of the Argentinean Flooding Pampas. The sites represent a wide range of soil conditions, hydrologic gradients, and floristic composition. Lotus glaber, a perennial herbaceous legume naturalised in the Flooding Pampas, was dominant at the four plant community sites. Its roots were highly colonised by AM fungi. Temporal variations in spore density, spore type, AM root colonisation, floristic composition and soil chemical characteristics occurred in each site and were different among sites. The duration of flooding had no effect on spore density but depressed AM root colonisation. Eleven different types of spores were recognized and four were identified. Two species dominated at the four sites: Glomus fasciculatum and Glomus intraradices. Spore density was highest in summer (dry season) and lowest in winter (wet season) with intermediate values in autumn and spring. Colonisation of L. glaber roots was highest in summer or spring and lowest in winter or autumn. The relative density of G. fasciculatum and G. intraradices versus Glomus sp. and Acaulospora sp. had distinctive seasonal peaks. These seasonal peaks occurred at all four sites, suggesting differences among AM fungus species with respect to the seasonality of sporulation. Spore density and AM root colonisation when measured at any one time were poorly related to each other. However, spore density was significantly correlated with root colonisation 3 months before, suggesting that high colonisation in one season precedes high sporulation in the next season.

Argentina↗
PubMed2005

Organic and mineral fertilization, respectively, increase and decrease the development of external mycelium of arbuscular mycorrhizal fungi in a long-term field experiment.

Effects of long-term mineral fertilization and manuring on the biomass of arbuscular mycorrhizal fungi (AMF) were studied in a field experiment. Mineral fertilization reduced the growth of AMF, as estimated using both measurements of hyphal length and the signature fatty acid 16:1omega5, whereas manuring alone increased the growth of AMF. The results of AMF root colonization followed the same pattern as AMF hyphal length in soil samples, but not AMF spore densities, which increased with increasing mineral and organic fertilization. AMF spore counts and concentration of 16:1omega5 in soil did not correlate positively, suggesting that a significant portion of spores found in soil samples was dead. AMF hyphal length was not correlated with whole cell fatty acid (WCFA) 18:2omega6,9 levels, a biomarker of saprotrophic fungi, indicating that visual measurements of the AMF mycelium were not distorted by erroneous involvement of hyphae of saprotrophs. Our observations indicate that the measurement of WCFAs in soil is a useful research tool for providing information in the characterization of soil microflora.

Biomarkers↗
PubMed2006

Associations between arbuscular mycorrhizal fungi and grasses in the successional context of a two-phase mosaic in the Chihuahuan Desert.

The hypothesis that plant species are more responsive to mycorrhiza in late than in early successional stages was assessed in grasses from a successional process occurring in two-phase mosaics from the Mexican Chihuahuan Desert. We estimated the density of spores of arbuscular mycorrhizal (AM) fungi and the AM colonization of pioneer and late-successional grasses in the field. In growth chamber experiments, we tested the effect of the native AM fungal community on grasses growing in soils from different successional stages. Spore density was higher in late than in early successional stages. Late-successional species were more responsive to AM (positive AM responsiveness) whereas pioneer species were nondependent on mycorrhiza or if associated to AM fungi, the interaction showed a negative AM responsiveness for the seedling stage. Our findings showed that late successional species fitted the proposed models of mycorrhizal performance, but the two pioneer species differed in their AM condition and responsiveness. This further supports the idea that AM interactions are more complex along the successional processes than the predictions of the more widely cited hypotheses.

Biomass↗
PubMed2006

Arbuscular mycorrhizal fungi increased early growth of two nontimber forest product species Dyera polyphylla and Aquilaria filaria under greenhouse conditions.

Nontimber forest products (NTFPs) represent an important source of income to millions of people in tropical forest regions, but some NTFP species have decreased in number and become endangered due to overexploitation. There is increasing concern that the planting stocks of Dyera polyphylla and Aquilaria filaria are not sufficient to sustain the yield of NTFPs and promote forest conservation. The objective of this study was to determine the effect of two arbuscular mycorrhizal (AM) fungi, Glomus clarum and Gigaspora decipiens, on the early growth of two NTFP species, D. polyphylla and A. filaria, under greenhouse conditions. The seedlings of both species were inoculated with G. clarum or G. decipiens, or uninoculated (control) under greenhouse conditions. Percentage of AM colonization, plant growth, survival rate, and nitrogen (N) and phosphorus (P) concentrations were measured after 180 days of growth. The percentage of AM colonization of D. polyphylla and A. filaria ranged from 87 to 93% and from 22 to 39%, respectively. Colonization by G. clarum and G. decipiens increased plant height, diameter, and shoot and root dry weights. Shoot N and P concentrations of the seedlings were increased by AM colonization by as much as 70-153% and 135-360%, respectively. Survival rates were higher in the AM-colonized seedlings at 180 days after transplantation than in the control seedlings. The results suggest that AM fungi can accelerate the establishment of the planting stocks of D. polyphylla and A. filaria, thereby promoting their conservation ecologically and sustaining the production of these NTFPs economically.

Apocynaceae↗
PubMed2006

Wetland dicots and monocots differ in colonization by arbuscular mycorrhizal fungi and dark septate endophytes.

As an initial step towards evaluating whether mycorrhizas influence composition and diversity in calcareous fen plant communities, we surveyed root colonization by arbuscular mycorrhizal fungi (AMF) and dark septate endophytic fungi (DSE) in 67 plant species in three different fens in central New York State (USA). We found colonization by AMF and DSE in most plant species at all three sites, with the type and extent of colonization differing between monocots and dicots. On average, AMF colonization was higher in dicots (58+/-3%, mean+/-SE) than in monocots (13+/-4%) but DSE colonization followed the opposite trend (24+/-3% in monocots and 9+/-1% in dicots). In sedges and cattails, two monocot families that are often abundant in fens and other wetlands, AMF colonization was usually very low (<10%) in five species and completely absent in seven others. However, DSE colonization in these species was frequently observed. Responses of wetland plants to AMF and DSE are poorly understood, but in the fen communities surveyed, dicots appear to be in a better position to respond to AMF than many of these more abundant monocots (e.g., sedges and cattails). In contrast, these monocots may be more likely to respond to DSE. Future work directed towards understanding the response of these wetland plants to AMF and DSE should provide insight into the roles these fungal symbionts play in influencing diversity in fen plant communities.

Ecosystem↗
PubMed2007

Taxon-specific PCR primers to detect two inconspicuous arbuscular mycorrhizal fungi from temperate agricultural grassland.

Taxon-specific polymerase chain reaction (PCR) primers enable detection of arbuscular mycorrhizal fungi (AMF, Glomeromycota) in plant roots where the fungi lack discriminative morphological and biochemical characters. We designed and validated pairs of new PCR primers targeted to the flanking regions of the variable domain 1 of the nuclear ribosomal large subunit RNA gene to specifically detect Acaulospora paulinae and an undescribed member of the Diversisporaceae. These two fungal taxa, sporulating late in soil-trap cultures and showing small, faintly coloured spores and weakly staining intraradical structures, were frequently found in roots of Trifolium repens from a high-input agricultural grassland. The newly developed PCR primers may thus enable studies on two inconspicuous AMF taxa that appear to have been overlooked in previous molecular AMF community analyses and for which no specific PCR primers have been published.

Crops, Agricultural↗
PubMed2006

Role of microtubules in tip growth of fungi.

Polarized cell growth is observed ubiquitously in all living organisms. Tip growth of filamentous fungi serves as a typical model for polar growth. It is well known that the actin cytoskeleton plays a central role in cellular growth. In contrast, the role of microtubules in polar growth of fungal tip cells has not been critically addressed. Our recent study, using a green fluorescent protein (GFP)-labeled tubulin-expressing strain of the filamentous fungus Aspergillus nidulans and treatment with an anti-microtubule reagent, revealed that microtubules are essential for rapid hyphal growth. Our results indicated that microtubule organization contributes to continuous tip growth throughout the cell cycle, which in turn enables the maintenance of an appropriate mass of cytoplasm for the multinucleate system. In filamentous fungi, the microtubule is an essential component of the tip growth machinery that enables continuous and rapid growth. Recent research developments are starting to elucidate the components of the tip growth machinery and their functions in many organisms. This recent knowledge, in turn, is starting to enhance the importance of fungal systems as simple model systems to understand the polar growth of cells.

Aspergillus nidulans↗
PubMed2006

Dissolved oxygen as principal parameter for conidia production of biocontrol fungi Trichoderma viride in non-Newtonian wastewater.

Dissolved oxygen (DO) concentration was selected as a principal parameter for translating results of shake flask fermentation of Trichoderma viride (biocontrol fungi) to a fermenter scale. All fermentations were carried out in a 7.5 l automated fermenter with a working volume of 4 l. Fermentation performance parameters such as volumetric oxygen transfer coefficient (k (L) a), oxygen uptake rate (OUR), rheology, conidia concentration, glucose consumption, soluble chemical oxygen demand, entomotoxicity and inhibition index were measured. The conidia concentration, entomotoxicity and inhibition index were either stable or improved at lower DO concentration (30%). Variation of OUR aided in assessing the oxygen supply capacity of the fermenter and biomass growth. Meanwhile, rheological profiles demonstrated the variability of wastewater during fermentation due to mycelial growth and conidiation. In order to estimate power consumption, the agitation and the aeration requirements were quantified in terms of area under the curves, agitation vs. time (rpm h), and aeration vs. time (lpm h). This simple and novel strategy of fermenter operation proved to be highly successful which can be adopted to other biocontrol fungi.

Animals↗
PubMed2005

Keratinophilic fungi recovered from muddy soil in Cairo vicinities, Egypt.

One hundred samples of muddy soil were collected from seven areas in the vicinity of Cairo and screened for the presence of keratinophilic fungi by using hair baiting isolation technique. Forty isolates of keratinophilic fungi were recovered and identified by recognition of their cultures, macro- and micromorphological features. Their physiological and molecular characteristics were studied by determination of their ubiquinone (Coenzyme Q) composition and DNA sequences of (ITS1-5.8S-ITS2) and 18S rRNA region sequences. The Keratinophilic isolates were identified as Chrysosporium carmichaelii, C. queenslandicum, C. zonatum, C. indicum, Aphanoascus mephitalis, and Uncinocarpus reesii. Chrysosporium zonatum was the most prevalent species and represented 42.5% of the total number of isolates. Each of C. carmichaelii and C. queenslandicum were equal in their prevalence and represented 15%. C. indicum comes next constituting 12.5%; followed by Uncinocarpus reesii which represented 10%. The least prevalent species in our study was Aphanoascus mephitalis, which was represented only 5% of the total keratinophilic isolates.

Ascomycota↗
PubMed2005

Eastern cottontail (sylvilagus floridanus) as carrier of dermatophyte fungi.

Eastern cottontail (Sylvilagus floridanus, fam. Leporidae), introduced into Piedmont (Italy) in the 1960s, was studied as carrier of dermatophyte fungi. Of 216 hair samples collected from animals culled between September 1999 and July 2000 in the Province of Alessandria (Piedmont, Italy) during a pest control project, 57 (26.4%) yielded dermatophyte colonies. As two different species of dermatophytes grew from two samples, a total of 59 fungal isolates (26.5%) were obtained. Six dermatophyte species both geophilic (M. gypseum, M. cookei, Trichophyton ajelloi, T. terrestre) and zoophilic (M. canis, T. mentagrophytes) were identified. No sex-related differences were found but season-related differences were observed. The highest prevalence of dermatophyte-positive samples was recorded in May-September, due to the geophilic fungi whose prevalence decreased during colder and increased during warmer months (p < 0.001). The presence of zoophilic dermatophytes, T. mentagrophytes, commonly associated with rodents, small mammals and lagomorphs and M. canis, usually correlated with domestic environment, did not change the whole year round. As Eastern cottontail has been showed to be a carrier of dermatophytes transmissible to man (M. canis, T. mentagrophytes and M. gypseum), it may represent a source of infection for gamekeepers, hunters and veterinarians.

Animals↗
PubMed1981

Fungal infection in chronic granulomatous disease. The importance of the phagocyte in defense against fungi.

Among 245 cases of chronic granulomatous disease which were evaluated, fungal infection occurred in 20.4 percent. Fungi encountered include Aspergillus, Torulopsis and Candida. In 18 percent of the patients with fungal infection, the disease was limited to soft tissue or bone; all did well. Most of the patients had fungal pneumonia and/or widely disseminated disease; diagnosis was usually confirmed by open lung biopsy. Patients with pneumonia or disseminated disease who received no therapy succumbed to infection, whereas more than half the patients who received antifungal therapy were cured. Modalities of treatment included antifungal chemotherapy, surgical removal of infected tissue and granulocyte transfusion. Although several patients showed dramatic improvement during granulocyte transfusions given in combination with antifungal chemotherapy, the improvement achieved was not statistically significant when compared with that achieved with chemotherapy alone. These results emphasized the importance of phagocytic cells in defense against fungi and the need for further evaluation of granulocyte transfusion therapy in compromised hosts in whom fungal infections develop.

Adolescent↗
PubMed1992

Fungi causing thread mould spoilage of vacuum packaged Cheddar cheese during maturation.

Thread mould is a defect which occurs sporadically in maturing vacuum packaged Cheddar cheese, caused by the growth of fungi in folds and wrinkles of the plastic film in which the cheese is packaged. Fungi were isolated and identified from 110 Cheddar cheese blocks exhibiting typical thread mould defects. The major causative species were found to be Cladosporium cladosporioides, Penicillium commune, C. herbarum, P. glabrum and a Phoma species. Yeasts were also frequently isolated from the cheese, the majority belonging to the genus Candida. Fungal species which can cause thread mould defects were also found in the cheese factory environment, on cheesemaking equipment, in air, and in curd and whey, providing a wide range of potential sources of contamination.

Air Microbiology↗
PubMed1993

Nematophagous fungi: prospective biological control agents of animal parasitic nematodes?

The rapidly escalating problem of anthelmintic resistance and the increasing concerns of chemical residues in livestock products and the environment pose serious threats to the future of chemotherapeutic control o f animal parasitic nematodes. One possible non-chemotherapeutic approach is biological control using nemotophagous fungi. Although Grønvold and colleagues recently described their experiments with two nematode-destroying fungi, Arthrobotrys and Duddingtonia, this alternate control option has received relatively little research attention. Here, Peter Waller broadens the discussion to consider the fundamental problems and prospects of this non-chemotheropeutic control strategy.

Journal Article↗
PubMed1993

Nematode-trapping fungi against parasitic cattle nematodes.

Interactions between larvae of bovine gastrointestinal nematode parasites and nematode-trapping fungi, such as Arthrobotrys and Duddingtonia species and strains have been studied in Denmark. In this article Jørn Grønvold, Jens Wolstrup, Peter Nansen and Svend Aage Henriksen discuss how these fungi are able to grow, trap and kill parasitic nematode larvae, both on agar in the laboratory and in cattle faeces in the field.

Journal Article↗
PubMed1991

Impact of sulphur dioxide exposure on conidial germination of powdery mildew fungi.

The impact of sulphur dioxide, in two different concentrations (286 microg m(-3) and 571 microg m(-3)) for various exposure periods, on conidial germination of some powdery mildew fungi was investigated in artificial treatment conditions. SO(2) in general was inhibitory for conidial germination of all the studied powdery mildew fungi and the species did not differ much from each other in their sensitivity to SO(2). The per cent conidial germination was increasingly inhibited with an increase in the concentration of SO(2). The concentration of SO(2) and the exposure period were important determinants of the inhibitory effect.

Journal Article↗
PubMed1983

Defense against infection with filamentous fungi in rainbow trout.

1. Healthy rainbow trout effectively resisted infection after subcutaneous inoculation with isolates of filamentous fungi recovered from cutaneous infections in fish. 2. The organisms were capable of growth on the tissues of freshly sacrificed fish following inoculation by the same method. 3. Microscopic examination of the inoculation sites revealed a prominent cellular infiltrate with higher proportions of neutrophils than those found at control sites or in peripheral blood. Inflammatory cells were found to be adherent to the surface of fungal hyphae removed from the inoculation site after 24-72 hr. 4. Neither precipitating antifungal antibody nor plasma factors capable of inhibiting fungal growth were found in the fish used in these experiments. 5. These studies suggest that inflammatory cells, particularly neutrophils, may be involved in the defense against filamentous fungi by rainbow trout.

Animals↗

Refine your search to explore more results.