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Reduction of the fungal community in soil caused by the addition of the fungicide methiram and the antibiotic actidione was accompanied by an intensive development of the community of copiotrophic bacteria. Irrespective of the fungal toxic substances used, there was a particularly conspicuous increase in the numbers of bacteria belonging to fluorescent Pseudomonas, among which three morphologically and physiologically different groups were distinguished. All the isolated strains of Pseudomonas were mycolytic and antibiotic for typical bacteria and actinomycetes; most of them decomposed methiram, but none decomposed actidione. Moreover, propagating rapidly in the presence of methiram were also bacteria from the species Vibrio proteolyticus (Aeromonas proteolyticus), and in the presence of actidione, bacteria from the species Sporocytophaga myxococcoides. The Vibrio strains, but not those of Sporocytophaga, were also mycolytic, like fluorescent Pseudomonas. Contrary to Pseudomonas, no strain of Vibrio nor of Sporocytophaga was antibiotic for typical bacteria and actinomycetes or able to decompose methiram or actidione.
Acta Mycologica
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2009
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tom 44
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nr 1
49-75
This article begins a four-part series, which presents the results of mycological research carried out in 2000-2007 in the agricultural landscape of the General Dezydery Chłapowski Landscape Park. This part includes description of the study area and field research methods, as well as a list and localities of 617 macrofungal taxa recorded in the Park. The next parts of this series will deal with: species that are rare, protected by law or recorded for the first time in Poland; the role of wooded patches for preservation of fungal diversity in the agricultural landscape; and changes in species diversity and structure of fungal communities in forest communities under strong human pressure.
A Scots pine forest, affected by the great cormorant colony, was studied by plot-based fungal survey method during the years 2010-2012 in Lithuania. Diversity and composition of fungal communities were investigated at five zones that had been influenced by different stages of breeding colony establishment: starting-point and almost abandoned cormorant colony part (zones A and B), active part (zones C and D), and the edge of the colony (zone E). The control zone G in undamaged by cormorants pine stand was assessed too. A total of 257 fungal species of ascomycetes including anamorphic fungi, basidiomycetes and zygomycetes were recorded. Seven species were registered for the first time in Lithuania. Species richness in the examined zones varied, lowest being in zones B (51 species), C (46) and D (73) and almost twice as high in the zones A and E (129 and 120, respectively). The comparison of fungal species compositions of different zones showed that their similarity was rather low (SS: 0.22–0.59). The most obvious changes in the trophic structure of fungal communities in the territory occupied by the bird colony were a strong decrease of mycorrhizal species, the presence of coprophilous fungi on forest litter, and the appearance of host-specialized fungi on alien and non-forest plants that have established in the disturbed forest.
Saprotrophic filamentous microfungi were isolated by means of the soil dilution method from soil samples collected from four locations in the Bellsund region of Spitsbergen (77°33'N, 14°31'E) representing the following forms of surface micro-relief: an old stormbank, a sorted circle, a frost fissure between tundra polygons, and the central part of a tundra polygon. The fungal isolates were identified and screened for their ability to grow at low temperatures. The oligotrophy of psychrophilic and psychrotrophic strains was then determined as the ability of growth on silica gel without a C source added. Differences in some physico-chemical properties were found between the soils sampled from the four sites. A total of 89 taxa from 17 genera were isolated. Most of the isolates were species of Mortierella, Penicillium, Chrysosporium and Phialophora, and half of them were psychro- philes. Fungal communities isolated from a frost fissure between tundra polygons (site 3) and from the central part of a tundra polygon (site 4) were dominated by psychrophiles but those isolated from an old stormbank (site 1) and a sorted circle (site 2) were predominantly psychrotrophic. Oligopsychrophilic taxa accounted for 27% and oligopsychrotrophic for 20% of all the isolated taxa but only from 0.7% to 11.7% and from 1.2% to 6.3% of the total number of cfu (colony forming unit) isolated from an individual site, respectively. The results of the present study suggest that the abundance of fungi in Arctic soil is mostly affected by the content of organic matter in the A horizon and the plant cover, but other factors, such as the stage of soil development and the micro-relief of the surface, are more important for species richness of fungal communities. Key words: Arctic, tundra, filamentous fungi, species richness, ecology.
The purpose of the studies conducted in the years 1996-1998 was to determine the quantitative and qualitative composition of bacterial and fungal communities in rhizosphere of soybean cultivated in monoculture and non-rhizosphere soil. Besides, the proportion of bacteria and fungi, which were distinguished by their antagonistic effect towards soil-borne pathogens was established. A microbiological analysis of 1g of dry weight of soil from rhizosphere of soybean resulted in 3.21 x 10⁶ to 8.70 x 10⁶ bacterial colonies and from 70.51 x 10³ to 123.74 x 10³ fungal colonies. In the case of non-rhizosphere soil, 3.50 x 10⁶ to 4.75 x 10⁶ bacterial colonies and 16.16 x 10³ to 51.38 x 10³ fungal colonies were obtained. Besides, soybean cultivation in monoculture had a negative effect on the number of antagonistic isolates of bacteria (Bacillus spp., Pseudomonas spp.) and fungi (Gliocladium spp., Penicillium spp., Trichoderma spp.). Smaller numbers of antagonistic bacteria and fungi in rhizosphere soil of soybean cultivated in monoculture as compared to non-rhizosphere soil, can prove little biological activity, which results in a worse phytosanitaty condition of the soil.
Effects of Scots pine wood amendment on the fungal community in forest soil infested with cockchafers and foraged or non-foraged by wild boars and hares were investigated. We hypothesized that sawdust amendment would increase the abundance of entomopathogenic and insect-associated species effective in cockchafer predation. The soil dilution method and morphotyping were used for fungal isolation and identification in order to quantify and qualify the viable components of the microbiota that are important for evaluating soil functions. There was usually increased abundance and decreased diversity of soil fungi one year after sawdust amendment. Application of pine sawdust more often increased than decreased the abundance of some insect-associated fungi or dermatophytes and keratinophilic species and decreased the number of cockchafer larvae. Abundance of Geomyces pannorum, Mortierella spp. + M. luteus, Pseudogymnoascus roseus, Tolypocladium inflatum and Trichoderma koningii increased, at least locally, whilst Chrysosporium merdarium, Penicillium spp. (including the most common P. citrinum, P. daleae and P. janczewskii), Sporothrix schenckii and Trichoderma spp. decreased. Application of pine sawdust under roots of 1-year-old Scots pine seedlings significantly increased the abundance of Phoma + Pyrenochaeta spp. in neighbouring soil, thus increasing the risk from Phoma blight. Trichoderma strigosum was among the dominants (frequency >5%). Another six and two Trichoderma species were among the subdominants (frequency 1–5%) and subrecedents (frequency <1%), respectively. Dermatophytes, coprophilous and keratinophilic species, e.g. Cephalotrichum, Chrysosporium merdarium or S. schenckii, occurred only or mostly in foraged plots. The altered communities resulting from pine sawdust amendment may contribute to biological control of the cockchafer larvae.
Scots pine sawdust, composted bark or coarse, post-harvest woody debris from conifers had been spread over the surface of barren forest soil before planting with Scots pine. The effects of the Scots pine sawdust, composted bark or coarse, post-harvest woody debris from conifers on the abundance and diversity of culturable fungi were investigated. The amendments were aimed at increasing the soil suppressiveness to Armillaria and Heterobasidion. The classical soil-dilution method was chosen for qualitative and quantitative analyses of fungal communities in soils because of its proven reliability and consistency. The soil was inhabited by saprotrophic fungi from Ascomycota and Zygomycota, including species known to be potential antagonists of Armillaria or H. annosum (i.e. Clonostachys + Trichoderma spp., Penicillium commune, P. daleae, P. janczewskii) or stimulants of Armillaria (i.e. Pseudogymnoascus roseus, Trichocladium opacum). Eleven years after treatment, the abundance and diversity of fungi, the abundance of P. commune, and locally the abundance of P. janczewskii increased, while Clonostachys + Trichoderma spp., and locally, P. daleae and T. opacum decreased. Amending the barren soil with organic matter does not guarantee effective, long-term suppressiveness of the sandy loam soil to Armillaria and Heterobasidion. Increased abundance of entomopathogenic and nematophagous species, 11 years after treatment, does suggest the long-term possibility of insect or nematode control in soil.
The mycological investigations were performed on three soil profiles, which represent the slightly, moderately and strongly mucked peat-muck soils located in the Biebrza Valley. The aim of the study was the comparison of quantitative-qualitative structures of the fungi communities in the chosen peat-muck soils. The results indicate that soil fungi communities from compared soils reveal only small degree of similarity. The variety in quantitative and in qualitative structure increase with increasing mucking of organic deposits. These results may suggest that decreasing moisture of habitat stimulates the development of soil fungi. The most numerous soil fungi communities were observed in the turf layer and subturf layer of all soils.
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