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Fungal Diversity (fungal + diversity)
Selected AbstractsPollen morphology, leaf surfaces, mycobiota diversity and leaf spots of three species of Zygophyllum growing along Cairo-Suez desert road, Eastern (Arabian) desert in EgyptFEDDES REPERTORIUM, Issue 1-2 2007S. M. El Naggar Three native species of Zygophyllum: Z. coccinum L., Z. decumbens L. and Z. simplex L. (Zygophyllaceae) have been investigated morphologically, palynologically and mycologically. Twenty-two fungal species belonging to 11 genera were collected from leaf surfaces (11 genera and 22 species) and anthers/ pollen grains (7, 13) of Zygophyllum coccinum, Z. decumbens and Z. simplex on Czapek-Dox agar at 25 °C. Fungal diversity of the two microhabitats is basically similar and the most prevalent fungi were Alternaria alternata /A. phragmospora, Cladosporium cladosporioides /C. herbarum and Ulocladium botrytis /U. consortiale. Alternaria alternata, Cladosporium cladosporioides and C. herbarum -leaf spots were rarely recorded in the three studied plant species. Leaf lamina size and sculpture of the studied taxa almost seem to be the most reliable factors of the fungal biodiversity on the studied plant species. On the other hand, reticulate-micro reticulate pollen type is the only pollen type recorded in the present study which reflects that the very narrow range of spectrum of fungal biodiversity between the studied plant species. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Pollenmorphologie, Blattoberfläche, mykobiotische Diversität und Blattflecken von drei Zygophyllum -Arten entlang der Wüstenstraße Kairo,Suez, Östliche (Arabische) Wüste Ägyptens Drei einheimische Zygophyllum -Arten (Z. coccinum, Z. decumbens und Z. simplex (Zygophyllaceae) wurden morphologisch, palynologisch und mykologisch untersucht. 22 Pilzarten aus elf Gattungen wurden von Blattoberflächen gesammelt (11 Gattungen, 22 Arten) und Antheren/Pollenkörner (7, 13) von Zygophyllum coccinum, Z. decumbens und Z. simplex mittels Czapek-Dox agar bei 25 °C untersucht. Die Pilzdiversität beider Mikrohabitate ist basisähnlich und die häufigsten Taxa sind: Alternaria alternata /A. phragmospora, Cladosporium cladosporioides /C. herbarum und Ulocladium botrytis /U. consor- tiale. Blattflecken von Alternaria alternata, Cladosporium cladosporioides und C. herbarum wurden auf den untersuchten Pflanzen selten verzeichnet. Die Größe der Blattlamina und die Skulptur der untersuchten Taxa scheinen die zuverlässigsten (häufigsten) Faktoren für die Pilz-Biodiversität auf den untersuchten Pflanzen zu sein. Andererseits ist der retikulate-microretikulate Pollentyp in vorliegender Studie der einzige Pollentyp, der dieses enge Spektrum der Pilz-Biodiversität zwischen den untersuchten Pflanzen aufzeigt (widerspiegelt). [source] Identification of the adherent microbiota on the gills and skin of poly-cultured gibel carp (Carassius auratus gibelio) and bluntnose black bream (Megalobrama amblycephala Yih)AQUACULTURE RESEARCH, Issue 9 2010Wenwen Wang Abstract PCR-denaturing gradient gel electrophoresis (DGGE) was applied to analyse the microbial community attached to the gills and skin of poly-cultured gibel carp (Carassius auratus gibelio) and bluntnose black bream (Megalobrama amblycephala Yih) and compare these results with those detected in the rearing water. The microbiota discussed included bacteria, fungi and a specific bacterial taxa of actinomycetes was also analysed. Proteobacteria, Firmicutes, Actinobacteria, Cyanobacteria, Ascomycota, Basidiomycota and some unclassified microbiota were identified. Based on our results, we concluded that: (1) the adherent bacterial/fungal communities on the gills and skin were different from those in the rearing water, (2) the bacterial/fungal diversities on fish gills were lower than that on fish skin, (3) the adherent bacterial/fungal communities on gill and skin of gibel carp were different from that of bluntnose black bream and (4) the adherent actinomycetal community showed certain similarity between the skin of different hosts. Based on our conclusions, we suggested that the topic investigated in the present study merits further investigations. [source] Ectomycorrhizal fungal succession in mixed temperate forestsNEW PHYTOLOGIST, Issue 2 2007Brendan D. Twieg Summary ,,Ectomycorrhizal (ECM) fungal communities of Douglas-fir (Pseudotsuga menziesii) and paper birch (Betula papyrifera) were studied along a chronosequence of forest development after stand-replacing disturbance. Previous studies of ECM succession did not use molecular techniques for fungal identification or lacked replication, and none examined different host species. ,,Four age classes of mixed forests were sampled: 5-, 26-, 65-, and 100-yr-old, including wildfire-origin stands from all four classes and stands of clearcut origin from the youngest two classes. Morphotyping and DNA sequences were used to identify fungi on ECM root tips. ,,ECM fungal diversities were lower in 5-yr-old than in older stands on Douglas-fir, but were similar among age classes on paper birch. Host-specific fungi dominated in 5-yr-old stands, but host generalists were dominant in the oldest two age classes. ECM fungal community compositions were similar in 65- and 100-yr-old stands but differed among all other pairs of age classes. ,,Within the age range studied, site-level ECM fungal diversity reached a plateau by the 26-yr-old age class, while community composition stabilized by the 65-yr-old class. Simple categories such as ,early stage', ,multi stage', and ,late stage' were insufficient to describe fungal species' successional patterns. Rather, ECM fungal succession may be best described in the context of stand development. [source] Summer drought decreases soil fungal diversity and associated phenol oxidase activity in upland Calluna heathland soilFEMS MICROBIOLOGY ECOLOGY, Issue 2 2008Hannah Toberman Abstract Natural moisture limitation during summer drought can constitute a stress for microbial communities in soil. Given globally predicted increases in drought frequency, there is an urgent need for a greater understanding of the effects of drought events on soil microbial processes. Using a long-term field-scale drought manipulation experiment at Clocaenog, Wales, UK, we analysed fungal community dynamics, using internal transcribed spacer-denaturing gradient gel electrophoresis (DGGE), over a 1-year period in the 6th year of drought manipulation. Ambient seasonality was found to be the dominant factor driving variation in fungal community dynamics. The summer drought manipulation resulted in a significant decline in the abundance of dominant fungal species, both independently of, and in interaction with, this seasonal variation. Furthermore, soil moisture was significantly correlated with the changes in fungal diversity over the drought manipulation period. While the relationship between species diversity and functional diversity remains equivocal, phenol oxidase activity was decreased by the summer drought conditions and there was a significant correlation with the decline of DGGE band richness among the most dominant fungal species during the drought season. Climatically driven events such as droughts may have significant implications for fungal community diversity and therefore, have the potential to interfere with crucial ecosystem processes, such as organic matter decomposition. [source] Comparative single-strand conformation polymorphism (SSCP) and microscopy-based analysis of nitrogen cultivation interactive effects on the fungal community of a semiarid steppe soilFEMS MICROBIOLOGY ECOLOGY, Issue 2-3 2001Jennifer L. Lowell Abstract The effects of nitrogen accretion on fungal diversity and community structure in early-seral (cultivated) and native (uncultivated) shortgrass steppe soils were evaluated using single-strand conformation polymorphism (SSCP) and microscopy in a comparative experiment. Selected haplotypes generated from fungal 18S gene fragments were also sequenced for species identification. Microscopy-based analyses showed significantly shorter fungal hyphal lengths in the early-seral control plots in comparison with the native control plots (P<0.0003), independent of nitrogen addition. Although diversity indices did not show significant differences between the plots, SSCP analyses indicated that fungal community structure differed in the native and early-seral control sites. In nitrogen-amended sites, gene sequences from dominant haplotypes indicated a shift to a more common nitrogen-impacted fungal community. While nitrogen amendments appear to be more important than cultivation in influencing these soil fungal communities, hyphal lengths were only decreased due to cultivation. The use of microscopic and molecular techniques, as carried out in this study, provided integrative information concerning fungal community responses to wide spread stresses being imposed globally on terrestrial ecosystems, that is not provided by the individual techniques. [source] Improvement of Cupressus atlantica Gaussen growth by inoculation with native arbuscular mycorrhizal fungiJOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2007L. Ouahmane Abstract Aims: The study aimed to determine whether inoculation with native arbuscular mycorrhizal (AM) fungi could improve survival and growth of seedlings in degraded soils of Morocco. Methods and Results: Soil samples were collected from the rhizosphere of Cupressus atlantica trees in the N'Fis valley (Haut Atlas, Morocco). AM spores were extracted from the soil, identified and this mixture of native AM fungi was propagated on maize for 12 weeks on a sterilized soil to enrich the fungal inoculum. Then C. atlantica seedlings were inoculated with and without (control) mycorrhizal maize roots, cultured in glasshouse conditions and further, transplanted into the field. The experiment was a randomized block design with one factor and three replication blocks. The results showed that a high AM fungal diversity was associated with C. atlantica; native AM fungi inoculation was very effective on the growth of C. atlantica seedlings in glasshouse conditions and this plant growth stimulation was maintained for 1 year after outplanting. Conclusions: Inoculation of C. atlantica with AM fungi increased growth and survival in greenhouse and field. Significance and Impact of the Study: The data indicate that use of native species of AM fungi may accelerate reforestation of degraded soils. Further studies have to be performed to determine the persistence of these mycorrhizae for a longer period of plantation and to measure the effects of this microbial inoculation on soil biofunctioning. [source] Ectomycorrhizal fungal communities at forest edgesJOURNAL OF ECOLOGY, Issue 2 2005IAN A. DICKIE Summary 1Ectomycorrhizal fungi are spatially associated with established ectomycorrhizal vegetation, but the influence of distance from established vegetation on the presence, abundance, diversity and community composition of fungi is not well understood. 2We examined mycorrhizal communities in two abandoned agricultural fields in Minnesota, USA, using Quercus macrocarpa seedlings as an in situ bioassay for ectomycorrhizal fungi from 0 to 20 m distance from the forest edge. 3There were marked effects of distance on all aspects of fungal communities. The abundance of mycorrhiza was uniformly high near trees, declined rapidly around 15 m from the base of trees and was uniformly low at 20 m. All seedlings between 0 and 8 m distance from forest edges were ectomycorrhizal, but many seedlings at 16,20 m were uninfected in one of the two years of the study. Species richness of fungi also declined with distance from trees. 4Different species of fungi were found at different distances from the edge. ,Rare' species (found only once or twice) dominated the community at 0 m, Russula spp. were dominants from 4 to 12 m, and Astraeus sp. and a Pezizalean fungus were abundant at 12 m to 20 m. Cenococcum geophilum, the most dominant species found, was abundant both near trees and distant from trees, with lowest relative abundance at intermediate distances. 5Our data suggest that seedlings germinating at some distance from established ectomycorrhizal vegetation (15.5 m in the present study) have low levels of infection, at least in the first year of growth. Distance from established vegetation represents an important gradient for ectomycorrhizal fungi, with different species occupying distinct niches along this gradient. This provides support for niche differentiation as a factor contributing to ectomycorrhizal fungal diversity. 6Ectomycorrhizal infection of seedlings is spatially complex, with high infection and high fungal diversity near trees, high infection but lower diversity at intermediate distances, and low infection and low fungal diversity distant from trees. This spatial complexity should be considered as a factor potentially influencing the establishment of ectomycorrhizal vegetation. [source] Detection and monitoring of anaerobic rumen fungi using an ARISA methodLETTERS IN APPLIED MICROBIOLOGY, Issue 6 2008S.E. Denman Abstract Aim:, To develop an automated ribosomal intergenic spacer region analysis (ARISA) method for the detection of anaerobic rumen fungi and also to demonstrate utility of the technique to monitor colonization and persistence of fungi, and diet-induced changes in community structure. Methods and Results:, The method could discriminate between three genera of anaerobic rumen fungal isolates, representing Orpinomyces, Piromyces and Neocallimastix species. Changes in anaerobic fungal composition were observed between animals fed a high-fibre diet compared with a grain-based diet. ARISA analysis of rumen samples from animals on grain showed a decrease in fungal diversity with a dominance of Orpinomyces and Piromyces spp. Clustering analysis of ARISA profile patterns grouped animals based on diet. A single strain of Orpinomyces was dosed into a cow and was detectable within the rumen fungal population for several weeks afterwards. Conclusions:, The ARISA technique was capable of discriminating between pure cultures at the genus level. Diet composition has a significant influence on the diversity of anaerobic fungi in the rumen and the method can be used to monitor introduced strains. Significance and Impact of the Study:, Through the use of ARISA analysis, a better understanding of the effect of diets on rumen anaerobic fungi populations is provided. [source] Co-existing grass species have distinctive arbuscular mycorrhizal communitiesMOLECULAR ECOLOGY, Issue 11 2003P. Vandenkoornhuyse Abstract Arbuscular mycorrhizal (AM) fungi are biotrophic symbionts colonizing the majority of land plants, and are of major importance in plant nutrient supply. Their diversity is suggested to be an important determinant of plant community structure, but the influence of host-plant and environmental factors on AM fungal community in plant roots is poorly documented. Using the terminal restriction fragment length polymorphism (T-RFLP) strategy, the diversity of AM fungi was assessed in 89 roots of three grass species (Agrostis capillaris, Festuca rubra, Poa pratensis) that co-occurred in the same plots of a field experiment. The impact of different soil amendments (nitrogen, lime, nitrogen and lime) and insecticide application on AM fungal community was also studied. The level of diversity found in AM fungal communities using the T-RFLP strategy was consistent with previous studies based on clone libraries. Our results clearly confirm that an AM fungal host-plant preference exists, even between different grass species. AM communities colonizing A. capillaris were statistically different from the others (P < 0.05). Although grass species evenness changed in amended soils, AM fungal community composition in roots of a given grass species remained stable. Conversely, in plots where insecticide was applied, we found higher AM fungal diversity and, in F. rubra roots, a statistically different AM fungal community. [source] 454 Pyrosequencing analyses of forest soils reveal an unexpectedly high fungal diversityNEW PHYTOLOGIST, Issue 2 2009M. Buée Summary ,,Soil fungi play a major role in ecological and biogeochemical processes in forests. Little is known, however, about the structure and richness of different fungal communities and the distribution of functional ecological groups (pathogens, saprobes and symbionts). ,,Here, we assessed the fungal diversity in six different forest soils using tag-encoded 454 pyrosequencing of the nuclear ribosomal internal transcribed spacer-1 (ITS-1). No less than 166 350 ITS reads were obtained from all samples. In each forest soil sample (4 g), approximately 30 000 reads were recovered, corresponding to around 1000 molecular operational taxonomic units. ,,Most operational taxonomic units (81%) belonged to the Dikarya subkingdom (Ascomycota and Basidiomycota). Richness, abundance and taxonomic analyses identified the Agaricomycetes as the dominant fungal class. The ITS-1 sequences (73%) analysed corresponded to only 26 taxa. The most abundant operational taxonomic units showed the highest sequence similarity to Ceratobasidium sp., Cryptococcus podzolicus, Lactarius sp. and Scleroderma sp. ,,This study validates the effectiveness of high-throughput 454 sequencing technology for the survey of soil fungal diversity. The large proportion of unidentified sequences, however, calls for curated sequence databases. The use of pyrosequencing on soil samples will accelerate the study of the spatiotemporal dynamics of fungal communities in forest ecosystems. [source] Ectomycorrhizal fungal succession in mixed temperate forestsNEW PHYTOLOGIST, Issue 2 2007Brendan D. Twieg Summary ,,Ectomycorrhizal (ECM) fungal communities of Douglas-fir (Pseudotsuga menziesii) and paper birch (Betula papyrifera) were studied along a chronosequence of forest development after stand-replacing disturbance. Previous studies of ECM succession did not use molecular techniques for fungal identification or lacked replication, and none examined different host species. ,,Four age classes of mixed forests were sampled: 5-, 26-, 65-, and 100-yr-old, including wildfire-origin stands from all four classes and stands of clearcut origin from the youngest two classes. Morphotyping and DNA sequences were used to identify fungi on ECM root tips. ,,ECM fungal diversities were lower in 5-yr-old than in older stands on Douglas-fir, but were similar among age classes on paper birch. Host-specific fungi dominated in 5-yr-old stands, but host generalists were dominant in the oldest two age classes. ECM fungal community compositions were similar in 65- and 100-yr-old stands but differed among all other pairs of age classes. ,,Within the age range studied, site-level ECM fungal diversity reached a plateau by the 26-yr-old age class, while community composition stabilized by the 65-yr-old class. Simple categories such as ,early stage', ,multi stage', and ,late stage' were insufficient to describe fungal species' successional patterns. Rather, ECM fungal succession may be best described in the context of stand development. [source] Culturing and direct DNA extraction find different fungi from the same ericoid mycorrhizal rootsNEW PHYTOLOGIST, Issue 1 2003Tamara R. Allen Summary ,,This study compares DNA and culture-based detection of fungi from 15 ericoid mycorrhizal roots of salal (Gaultheria shallon), from Vancouver Island, BC Canada. ,,From the 15 roots, we PCR amplified fungal DNAs and analyzed 156 clones that included the internal transcribed spacer two (ITS2). From 150 different subsections of the same roots, we cultured fungi and analyzed their ITS2 DNAs by RFLP patterns or sequencing. We mapped the original position of each root section and recorded fungi detected in each. ,,Phylogenetically, most cloned DNAs clustered among Sebacina spp. (Sebacinaceae, Basidiomycota). Capronia sp. and Hymenoscyphus erica (Ascomycota) predominated among the cultured fungi and formed intracellular hyphal coils in resynthesis experiments with salal. ,,We illustrate patterns of fungal diversity at the scale of individual roots and compare cloned and cultured fungi from each root. Indicating a systematic culturing detection bias, Sebacina DNAs predominated in 10 of the 15 roots yet Sebacina spp. never grew from cultures from the same roots or from among the > 200 ericoid mycorrhizal fungi previously cultured from different roots from the same site. [source] Effects of Forest Use on Aphyllophoraceous Fungal Community Structure in Sarawak, MalaysiaBIOTROPICA, Issue 3 2008Satoshi Yamashita ABSTRACT Aphyllophoraceous fungi are expected to reflect changes in the environmental conditions caused by forest use. To reveal the effects of forest uses on the fungal community structure, we performed a 3-month survey of aphyllophoraceous species in five forest types (undisturbed primary forest, isolated patches of primary forest, old and young fallow forest, and rubber plantations) in Sarawak, Malaysia in 2005. We used a canonical correspondence analysis (CCA) to reveal the relationships between fungal community composition and the environmental variables (canopy openness, soil water potential, amount and composition of coarse woody debris, litter mass, basal area, plant species composition). A total of 155 samples from 67 species were collected during the study period. The fungal species density represented by the number of species in a transect differed significantly among forest types. The fungal species density increased significantly with increasing number of pieces of coarse woody debris (CWD), but decreased significantly with increasing the scores of second axis of principal component analysis (PCA) for plant species composition. In the CCA ordination, automatic forward selection revealed that only the number of pieces of CWD significantly affected the fungal species composition. The occurrences of Flabellophora licmophora, Coriolopsis retropicta, Microporus vernicipes, and Amauroderma subrugosum were positively correlated with the number of pieces of CWD. Our study clearly demonstrated that forest use negatively affected aphyllophoraceous fungal diversity and suggest that the quantity of CWD would be an important determinant of fungal diversity and composition. [source] | ||||||||||||||||||||||