Showing papers on "Mycelium published in 1986"
TL;DR: Carbon transfer between plants of Pinus spp.
Abstract: It is increasingly evident that in natural plant communities the vegetative mycelia of ectomycorrhizal fungi can form networks of hyphal interconnections which link the root systems of their host plants in both intraand inter-specific combinations. Root observation chambers have been used to examine the development of these mycelial networks and to assess their functional significance as pathways for the transfer of assimilate between individuals in a range of host-fungus associations. Carbon transfer between plants of Pinus spp. is significantly increased by the presence of mycelial connections and preliminary evidence suggests that such transfer may be enhanced where concentration gradients are induced by shading. The significance of these experimental results is discussed in relation to nutrient cycling processes in natural ecosystems.
263 citations
212 citations
TL;DR: An isolate of Trichoderma harzianum directly attacked and lysed the mycelium and sclerotia of Sclerotium rolfsii when the two fungi were grown in dual culture and was found tolerant to PCNB (Pentachloronitrobenzene) in vitro.
Abstract: An isolate of Trichoderma harzianum (IMI no. 238493) directly attacked and lysed the mycelium and sclerotia of Sclerotium rolfsii when the two fungi were grown in dual culture. The type of interactions between the antagonist and pathogen were hyphal coiling, entry through haustoria‐like structure and direct entry in the hyphae and sclerotia of S. rolfsii, the host fungus. In a glasshouse experiment, T. harzianum applied in the form of sorghum culture to 5. rolfsii infested soil gave as high as 76 and 88% disease control in first and second growth cycle of sugarbeet seedlings respectively. The degree of disease control obtained increased with the increase in the amount of T. harzianum applied. This isolate of T. harzianum was found tolerant to PCNB (Pentachloronitrobenzene) in vitro. PCNB at low concentration when integrated with T. harzianum improved disease control. Under field conditions, integration of PCNB and T. harzianum significantly reduced the incidence of Sclerotium root rot (76% diseas...
89 citations
TL;DR: Due to the large absorbing surface of the mycelium that grows in the upper parts of the soil mushrooms take up higher amounts of137Cs and40K than lichens, but only the long-lived radionuclides125Sb and60Co could be measured; but not the short-lived fission-products144Ce,95Zr and95Nb which probably decayed before absorption into the my celium.
Abstract: Due to the large absorbing surface of the mycelium that grows in the upper parts of the soil mushrooms take up higher amounts of137Cs and40K than lichens. Besides these nuclides only the long-lived radionuclides125Sb and60Co could be measured; but not the short-lived fission-products144Ce,95Zr and95Nb which probably decayed before absorption into the mycelium. These nuclides, however, are present in lichens because of their surface structures which enable high foliar deposition. The137Cs-content of lichens is probably due to absorption by the mycobiont and seems to be used to satisfy their potassium-requirements. Mushrooms on the other hand are characterized by a relatively stable potassium-content and a wide ranging137Cs-content which depends on the availability in different substrates. Occasionally the natural radionuclides238U and226Ra could be detected in mushroom and lichen samples, showing no correlation with the natural radionuclide content of the soil.
88 citations
TL;DR: Wood blocks colonized by the basidiomycetes Hypholoma fasciculare and Phanerochaete velutina were placed in plastic trays containing moist unsterilized soil and grew out radially from the inoculum blocks in the form of networks of mycelial cords.
Abstract: SUMMARY: Wood blocks colonized by the basidiomycetes Hypholoma fasciculare and Phanerochaete velutina were placed in plastic trays containing moist unsterilized soil. Both fungi grew out radially from the inoculum blocks in the form of networks of mycelial cords. When a second, uncolonized wood block, or set of wood blocks, was provided as a ‘bait’ about 5 cm from the inoculum block, marked changes in the form and growth characteristics of the mycelial network followed contact with the bait. These changes were influenced by the relative size of inoculum and bait and included inhibition of radial extension from the inoculum; stimulation of development of connective mycelium; directed growth responses to the bait; fan-shaped outgrowth with conserved polarity from the bait; eventual regression of non-connective mycelium originating from the inoculum. These effects presumably reflect the capacity of the mycelium to behave as a co-ordinated unit and to economize on biomass when growing between discontinuously supplied resource units.
87 citations
TL;DR: Germination rate of surface-sterilized chlamydospores of the vesicular-arbuscular (VA) mycorrhizal endophyte Glomus mosseae was significantly hastened by the presence of freeliving fungi in a time-course experiment on water-agar.
Abstract: Germination rate of surface-sterilized chlamydospores of the vesicular-arbuscular (VA) mycorrhizal endophyte Glomus mosseae was significantly hastened by the presence of freeliving fungi in a time-course experiment on water-agar. The fungi also stimulated hyphal growth, while vegetative spores formed only on the mycelium arising from resting spores grown in the presence of such free-living micro-organisms. The time of appearance of vegetative spores was related to the time when the free-living fungi were added. The interest in soil biology and ecology of these microbe-microbe relationships involving VA fungi is discussed.
84 citations
TL;DR: Five entomopathogenic Hyphomycetes were tested under field conditions for biological control of brown planthopper, Nilaparvata lugens (Stal), in rice and the mycelium preparation sporulated on the plant and was as effective as the conidia suspension in infecting brown planTHopper.
Abstract: Five entomopathogenic Hyphomycetes were tested under field conditions for biological control of brown planthopper, Nilaparvata lugens (Stal), in rice. Suspensions of conidia of Metarhizium anisopliae (Metsch.) Sorokin, M. flavoviride Gams & Roszypal, Beauveria bassiana (Bals.) Vuill., and Hirsutella citriformis Speare were applied at a rate of 4–5.1012 conidia per ha. In addition, M. anisopliae and Paecilomyces lilacinus (Thorn) Samson were applied as preparations of dry mycelium at a rate of 1.5–2 kg/ha. Mortality due to fungus infection ranged from 63 to 98% 3 weeks after application. There were no consistent differences between fungus species. The mycelium preparation sporulated on the plant and was as effective as the conidia suspension in infecting brown planthopper. Hyphomycetous fungi should be evaluated further for control of brown planthopper in rice.
83 citations
TL;DR: Antitumor glucan (grifolan LE) was purified from LELFD by diethylaminoethyl-Sephadex A-25 chromatography and ethanol precipitation and showed antitumor activity against sarcoma 180 cells in ICR mice.
Abstract: Chemical characterization of the extracts, and purification and structural characterization of an antitumor glucan obtained from liquid-cultured mycelium of Grifola frondosa are described in this paper. The mycelium (13 g dry weight/1 culture) was extracted successively with hot water (LMHW, 14.9 g/100 g mycelium), cold alkali (LMCA, 6.3 g/100 g mycelium), and hot alkali (LMHA, 4.5 g/100 g mycelium). Each extract was dialyzed and then the polysaccharide fraction was precipitated with ethanol. Another portion of the mycelium was incubated with a buffer composed of glucose (5.0%) and citric acid, pH 4.5, for 3 d and the supernatant was obtained (LELFD, 50 g/100 g mycelium). The brothe was dialyzed and the nondialyzable fraction was precipitated with ethanol (LLFD, 1.3 g/1 culture). All of the above fractions were composed of glucose as the major carbohydrate. Except for LMHW, all fractions showed antitumor activity against sarcoma 180 cells in ICR mice. The activity was the strongest in the LELFD fraction. Antitumor glucan (grifolan LE) was purified from LELFD by diethylaminoethyl-Sephadex A-25 chromatography and ethanol precipitation. Grifolan LE gave Mr of more than 5×106 (8 M urea/0.2 N NaOH), [α]D -6°--9° (c=0.1%; 0.3 N NaOH), and showed metachromasy coupled with Congo red. By carbon-13 nuclear magnetic resonance spectra and methylationanalyses, grifolan LE was found to be a branched β-1, 3-glucan containing a branch at C-6 of every three main chain glucosyl units.
76 citations
TL;DR: The onset of sporogenesis was always accompanied by a new accumulation of glycogen in sporulating hyphae and during spore maturation the accumulated polysaccharide was degraded and the possible roles of both carbohydrates in the developmental cycle of Streptomyces are discussed.
Abstract: Summary: Streptomyces antibioticus accumulated glycogen and trehalose in a characteristic way during growth on solid medium. Glycogen storage in the substrate mycelium took place during development of the aerial mycelium. The concentration of nitrogen source in the culture medium influenced the time at which accumulation started as well as the maximum levels of polysaccharide stored. Degradation of these glycogen reserves was observed near the beginning of sporulation. The onset of sporogenesis was always accompanied by a new accumulation of glycogen in sporulating hyphae. During spore maturation the accumulated polysaccharide was degraded. No glycogen was observed in aerial non-sporulating hyphae or in mature spores. Trehalose was detected during all phases of colony development. A preferential accumulation was found in aerial hyphae and spores, where it reached levels up to 12% of the cell dry weight. The possible roles of both carbohydrates in the developmental cycle of Streptomyces are discussed.
74 citations
TL;DR: Comparing the chemical constituents of fruiting bodies produced on cotton straw and mycelial pellets revealed several similarities in total nitrogen, protein, glycogen, fatty acids, RNA, and ash content, but differences were observed in the contents of six amino acids.
Abstract: Pleurotus ostreatus `Florida9 was grown in submerged liquid culture. The biomass yield of the fungus, grown for 3 days in 2-liter fermentors, where the mycelial pellets measuring 5 mm in diameter were formed, was 11.7 g (dry weight)/liter. Comparing the chemical constituents of fruiting bodies produced on cotton straw and mycelial pellets revealed several similarities in total nitrogen, protein, glycogen, fatty acids, RNA, and ash content. Differences were observed in the contents of six amino acids. Although the total fatty acid content was similar, there were more saturated fatty acids in the mycelium. Cell wall composition, typical for basidiomycetes, was observed in both mycelium and fruiting bodies, with laminarin as the main polymer. Images
69 citations
TL;DR: The purified laccase was a single protein of Mr 59000, pI 2.9 and was active on o-diphenyl substrates and Amino acid composition and N-terminal sequence (15 residues) were determined.
Abstract: Laccase was purified from culture broth ofPleurotus ostreatus mycelium. The enzyme was a single protein of Mr 59000, pI 2.9 and was active on o-diphenyl substrates. Amino acid composition and N-terminal sequence (15 residues) were determined. Polyclonal anti-laccase antibodies were obtained.
TL;DR: The numbers of bugs were significantly reduced in all fungal treatments compared to the control over a period up to 9 weeks, except in one of the plots where severe drought hampered control.
TL;DR: The mobilities of three enzymes, esterase (EST), glutamate oxaloacetate transaminase (GOT) and peptidase (PEP), during polyacrylamide gel electrophoresis have been used to identify individual species of vesicular–arbuscular mycorrhizal fungi in roots.
Abstract: Summary
The mobilities of three enzymes, esterase (EST), glutamate oxaloacetate transaminase (GOT) and peptidase (PEP), during polyacrylamide gel electrophoresis have been used to identify individual species of vesicular–arbuscular mycorrhizal fungi in roots. The enzyme banding patterns obtained from mycorrhizal root extracts were compared with those of uninfected roots. Chlamydospores, external mycelium and internal mycelium (obtained by enzymic digestion of host root tissue) were used as controls to confirm the position of the fungal specific enzyme bands on the gels. Glomus caledonium (Nicol. and Gerd.) Trappe and Gerd. and Glomus mosseae (Nicol. and Gerd.) Gerd. and Trappe could be detected in leek (Allium porrum L.) roots against the host background by the mobility of bands of EST, GOT and PEP activity and it was possible to detect both G. caledonium and G. mosseae in leek roots which had been grown in the presence of a mixed inoculum, by staining for any of these three enzymes. Glomus mosseae could be identified in maize (Zea mays L.) roots by location of GOT and PEP activity but the major bands of EST, GOT and PEP activity in G. caledonium had the same mobility as those of maize and so this fungus could not be easily identified in this host using these experimental conditions. Glomus fasciculatum (Thaxter sensu Gerd.) Gerd. and Trappe type E3 had a characteristic PEP band which was separable from leek and maize host bands and this fungus could also be identified in maize roots by the position on the gel of fungal GOT activity.
TL;DR: Strain hOG301 was stable and exhibited mycelial morphology over a wide temperature range (5 to 40 degrees C) in several media and showed morphological features described in the literature as being typical of both true hyphae and pseudohyphae, the first report of aMycelial C. albicans that is stable at ambient temperatures.
Abstract: In this paper we describe the isolation of a novel strain of Candida albicans which is a mycelium at ambient temperatures. Mutagenesis of C. albicans ATCC 10261 with N-methyl-N-nitro-N-nitrosoguanidine followed by plating on solid media at 28 degrees C yielded colony morphology variants which were characterized by a raised, rough-surfaced colony of irregular outline in marked contrast to the flat, shiny circular colonies of the parental 10261 strain. One mutant colony, hOG301, was studied in detail. Strain hOG301 was stable and exhibited mycelial morphology over a wide temperature range (5 to 40 degrees C) in several media. The hyphae comprising hOG301 mycelium were examined by light microscopy, scanning electron microscopy, and transmission electron microscopy and showed morphological features described in the literature as being typical of both true hyphae and pseudohyphae. In contrast to 10261, hOG301 was not pathogenic after intraperitoneal injection in mice. This is the first report of a mycelial C. albicans that is stable at ambient temperatures.
TL;DR: In this paper, mass loss of barley straw exposed at 10 cm depth in an unfertilized field plot was followed for 2 years, and the amount of FDA-active fungal mycelium remained at a low and constant level for the 2 years while total fungal biomass started to increase after the first winter.
Abstract: Mass loss of barley straw exposed at 10 cm depth in an unfertilized field plot was followed for 2 yr. Organic-chemical changes in the decomposing straw were also followed as well as the ingrowth of flourescein-diacetate-active (FDA) fungal mycelium and total mycelium. Mass loss was faster during the first year than in the second. Concentration of total solubles decreased initially to a low but fairly constant level which was maintained for 2 yr. Total solid polysaccharides increased initially, but began to decompose after about 200 days, while sulfuric-acid lignin, which also increased initially, later began to decompose slightly. The amount of FDA-active fungal mycelium remained at a low and constant level for the 2 yr while total fungal biomass started to increase after the first winter and continued for the rest of the investigation. Within 3 weeks about 30% of the N had been leached from the straw and after the first winter about 50% of the N was released. After that a net uptake took place and after 2 yr the total net release was about 25%. The relative amount of N increased continuously after the first winter and was linear to mass loss.
TL;DR: Sorghum infected with vesicular-arbuscular mycorrhiza was better equipped than non-infected sorghum to compete with young cabbage for soil nutrients and nutrient transfer seemed to depend on the nutrient status of the nurse plant.
Abstract: The effect of host plant infection on the mycorrhizal response of non-host plants was examined in a double pot system. The absence of nutrient transfer from a mature host (sorghum) to a young-non-host (cabbage) indicates the inability of the atypical infection of non-host plants to take up nutrients. However, nutrient transfer between mature and young sorghum plants, possibly through mycelial connections, was observed. The direction of this nutrient transfer seemed to depend on the nutrient status of the nurse plant. Because the nurse plants were grown in P-deficient soil, mature sorghum competed with young sorghum plants. Sorghum infected with vesicular-arbuscular (VA) mycorrhiza was better equipped than non-infected sorghum to compete with young cabbage for soil nutrients.
TL;DR: It is concluded that aerial mycelium formation by Streptomyces results from a decrease in the pool of GTP (or GDP), whereas antibiotic synthesisresults from a different signal(s).
Abstract: Summary: Aerial mycelium formation by Streptomyces sp. MA406-A-1, a formycin-producing strain, was suppressed by the presence of excess nutrient. In such suppressed cultures, decoyinine, which specifically inhibits GMP synthetase, initiated the formation of aerial mycelium at concentrations which only partially inhibited growth. The intracellular GTP pool of organisms growing in liquid culture markedly decreased on the addition of decoyinine. Decoyinine was also effective in initiating aerial mycelium formation of three other Streptomyces spp. examined. Regardless of the successful initiation of aerial mycelium formation, the ability of the cells to produce antibiotics (formycin or actinomycin D) did not increase, but decreased, on the addition of decoyinine. It is concluded that aerial mycelium formation by Streptomyces results from a decrease in the pool of GTP (or GDP), whereas antibiotic synthesis results from a different signal(s).
TL;DR: The fungus Fusarium moniliforme was entrapped in sodium alginate gel to synthesize gibberellic acid from paneer (cheese) whey resulting in comparatively higher yield than free fungal mycelium under optimized conditions.
TL;DR: The GC/MS analysis of trimethylsilyl derivatives of extracts from the culture medium and from the mycelium of Ophrys lutea Cav.
Abstract: Summary
The GC/MS analysis of trimethylsilyl derivatives of extracts from the culture medium and from the mycelium of Ophrys lutea Cav., a mycorrhizal fungus grown in a liquid culture medium, revealed the ability of this fungus to synthesize indole-3-ethanol and indole-3-acetic acid.
The identification of these compounds in the liquid medium and in the mycelial extracts suggested their transference from the fungus to the host during the establishment of mycorrhizas.
TL;DR: In this paper, the authors reported that the best results were obtained with mycelium entrapped in κ-carrageenan and in cubes of polyurethane sponge, and that the maximum protease activity secreted in the tenth cycle being about 85% of that produced in the initial use.
01 Jan 1986
TL;DR: In this article, the formation and regeneration of protoplasts from the ectomycorrhizal basidiomycete Luccaria bicolor using the lytic enzyme preparation NovoZyme 234 was studied.
Abstract: KROPP, B. R., and J. A. FORTIN. 1986. Formation and regeneration of protoplasts from the ectomycorrhizal basidiomycete Luccaria bicolor. Can. J. Bot. 64: 1224 1226. Protoplasts were released from dikaryotic mycelium of the ectomycorrhizal basidiomycete Luccaria bicolor using the lytic enzyme preparation NovoZyme 234. Protoplast release depended strongly on mycelium age, osmotic stabilizer, and temperature. The protoplasts could regenerate to form both monokaryotic and dikaryotic cultures capable of forming normal ectomycorrhizae with Pinus banksiana.
TL;DR: Protoplasts were released from dikaryotic mycelium of the ectomycorrhizal basidiomycete Laccaria bicolor using the lytic enzyme preparation NovoZyme 234 and could regenerate to form both monokaryotic and dkaryotic cultures capable of forming normal ectomyCorrhizae with Pinus banksiana.
Abstract: Protoplasts were released from dikaryotic mycelium of the ectomycorrhizal basidiomycete Laccaria bicolor using the lytic enzyme preparation NovoZyme 234. Protoplast release depended strongly on mycelium age, osmotic stabilizer, and temperature. The protoplasts could regenerate to form both monokaryotic and dikaryotic cultures capable of forming normal ectomycorrhizae with Pinus banksiana.
TL;DR: Sialic acid residues in conidia are linked to galactopyranosyl units as indicated by the increased reactivity of neuraminidase-treated cells with peanut agglutinin.
Abstract: Sialic acids were characterized on the cell surface of conidia and hyphae of Fonsecaea pedrosoi, one of the agents of chromoblastomycosis. Neuraminidase-treated conidia had a reduced negative electrophoretic mobility and, in comparison with untreated cells, bound fewer particles of colloidal iron hydroxide and of cationized ferritin. Sialic acid residues in conidia are linked to galactopyranosyl units as indicated by the increased reactivity of neuraminidase-treated cells with peanut agglutinin. N-acetylneuraminic acid was the only derivative found in the mycelium whereas conidia contained both N-glycolyl- and N-acetylneuraminic acids.
TL;DR: The different stages of development of this fungus were studied by light microscopy and scanning electron microscopy to illustrate the morphology and surface structures of conidia and mycelium.
Abstract: Exophiala pisciphila is a dematiaceous fungus that belongs to a group of fungi known as the 'black yeasts'. It was isolated from the skin lesions of a smooth dogfish, Mustelus canis Mitchill, that had been born in the shark exhibit tank of the New York Aquarium. The different stages of development of this fungus were studied by light microscopy and scanning electron microscopy to illustrate the morphology and surface structures of conidia and mycelium. The list of marine and fresh water fish, which have been infected by Exophiala spp. and Exophiala-like fungi has been up-dated. Potato Dextrose Agar and Malt Agar proved to be the best growth media, while Corn Meal Agar proved to be the best medium for studying the morphological features of the conidia and mycelial development of E. pisciphila, which exhibited polymorphic conidiogenesis.
TL;DR: Secretion of enzymes active on native cellulose is enhanced on a diet of leaves already partially degraded by fungal enzymes, and specific enzyme secretion is enhanced by the presence in the diet of exposed, accessible substrates.
Abstract: SUMMARY. 1. Sets of ten Gammarus pulex fed on controlled diets of sterile alder leaves, or fungal mycelium, or alder leaves incubated for 10 days with an aquatic hyphomycete, were assayed for cellulase, β-1,3-glucanase an d chiitinase activity and compared with (a) animals taken directly from the stream, (b) animals starved for 2 days, and (c) enzyme activity in fungal mycelium.
2. Gut enzyme activity was compared on natural substrates of sterile leaves, mycelium and inoculated leaves as well as on model substrates.
3. G. pulex secretes an endogenous coupled cellulase system capable of degrading native cellulose in plant cell walls. It also secretes β-1,3-glucanase and chitinase capable of degrading fungal cell walls thus affording access for gut enzymes to cell contents.
4. Secretion of enzymes active on native cellulose is enhanced on a diet of leaves already partially degraded by fungal enzymes. Gut enzymes extract more reducing sugar from this substrate than from sterile leaves. Specific enzyme secretion is enhanced by the presence in the diet of exposed, accessible substrates. Fungal enzymes do not appear to contribute to the digestive processes of G. pulex.
TL;DR: The germination pattern of six species of fungi on synthetic soil containing antibiotic-producing or non-antibiotic-producing micro-organisms was similar to that on natural soil.
Abstract: SUMMARY: The germination pattern of six species of fungi on synthetic soil containing antibiotic-producing or non-antibiotic-producing micro-organisms was similar to that on natural soil. Sterilization by autoclaving destroyed the fungistatic effect of both natural and synthetic soils. Mixed microorganisms were more effective than bacteria, actinomycetes or fungi alone in inducing fungistasis in synthetic soil. The percentage germination of Exserohilum rostratum and Bipolaris maydis on both natural and synthetic soils increased with increase in the proportion of silica sand added. Bacteriostasis, actinostasis and fungistasis occurred concurrently in the synthetic soil, which also induced lysis of mycelia of Neurospora tetrasperma. Preincubation on natural or synthetic soil rendered nutrient agarose blocks incapable of supporting germination of nutrient-dependent fungi without reducing their ability to support germination of nutrient-independent fungi. Individual groups of micro-organisms were not as effective as mixed micro-organisms in causing diffusion of nutrients from agarose blocks to synthetic soil.
TL;DR: Voltammetric analysis of medium which had supported growth of the fungus showed that copper added at a final concentration of 40 μM was complexed, and energy-dependent copper uptake from 2-(N-morpholino)ethanesulfonic acid buffer at pH 5.5 containing 40μM copper could not be demonstrated in nongrowing mycelium.
TL;DR: Mycelium of Mucor flavus Bainier adsorbed calcium silicate, elemental sulphur, lead sulphide and zinc dust from water suspension as mentioned in this paper, and ochre (ferric hydroxide) from acid mine drainage.
TL;DR: The antisera were used for the detection and differentiation of fungi in thin sections of roots of Rhododendron by an indirect immunocytochemical procedure using colloidal gold-labelled goat antirabbit immunoglobin G.
Abstract: Antisera were prepared from fruiting structures of a Clavaria sp. found growing in the vicinity of Rhododendron plants and from mycelium of Pezizella ericae grown in culture. The antisera were used for the detection and differentiation of fungi in thin sections of roots of Rhododendron by an indirect immunocytochemical procedure using colloidal gold-labelled goat antirabbit immunoglobin G. Three distinct fungal types could be detected in roots: hyphae that reacted only with the Clavaria antiserum; hyphae that reacted only with the Pezizella antiserum; and hyphae that did not react with either antiserum.
TL;DR: P. brasiliensis conidia were studied for their ability to grow as yeasts or as molds according to temperature and it was found that such conidia shared the ability of the parent mycelium to transform directly into multiple-budding yeast cells at 36 degrees C.
Abstract: P. brasiliensis conidia were studied for their ability to grow as yeasts or as molds according to temperature. Using a microculture system we found that such conidia shared the ability of the parent mycelium to transform directly into multiple-budding yeast cells at 36°C or to produce germ tubes and branching mycelia if kept at 22°C.