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1.
Eumycetoma is a mycotic disease caused by saprophytic soil fungi that are usually inoculated through minor injuries. A case of mycetoma in a Brazilian farmer aged71 years is reported. This patient presented erythema and edema on the dorsal surface of the left hand with multiple crusted and cicatricial lesions. No macroscopic grains were observed. The histopathological findings showed grains consisted of numerous hyphae which stained well with Gomori-Grocott method. This material obtained by cutaneous biopsy was submitted to culture on Sabouraud’s medium and the colonies were identified as Fusarium solani. The radiological studies revealed bone osteolytic lesions and the ultrasound showed pseudocysts and fistulae at the site of this infection. The patient was treated with oral ketoconazole with a good clinical response. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

2.
A fungus was isolated from the stem cuttings of Taxus celebica, which produced paclitaxel in liquid-grown cultures. The fungus was identified as Fusarium solani based on colony characteristics, morphology of conidia and the 26S rDNA sequence. Paclitaxel was identified by chromatographic and spectroscopic comparison with authentic paclitaxel and its cytotoxic activity towards Jurkat cells in vitro.  相似文献   

3.
The pathogenicity of Cylindrocarpon tonkinense in the cornea was evaluated and compared with that of Fusarium solani in rabbits. F. solani was inoculated into the right eyes of 14 rabbits and C. tonkinense was into the left eyes of same rabbits. The corneal lesions of both eyes were examined carefully by slit lamp every day for three weeks and the severity of infections were compared each other. For histopathologic study, several eyes were enucleated periodically. C. tonkinense has a pathogenicity equally strong as F. solani in this inculum size (104 microconidia per cornea) and produced severe infection in rabbit eyes.  相似文献   

4.
Hartung C  Lugo MR 《Mycopathologia》1996,135(3):183-185
A strain ofFusarium solani sensu Snyder & Hansen invaded the eggs of the insectPanstrongylus geniculatus in a vivarium. None of the invaded eggs hatched. To establish experimentally the pathogenicity of thisFusarium species against the eggs ofP. geniculatus, the fungus and the eggs were incubated together under different relative humidities and temperatures. At 64% relative humidity and 26 °C, the fungus grew well colonizing and penetrating all of the chorions.Three embryos died and were also colonized byF. solani. Only 4 nymphs hatched and survived to day 20. It is concluded that the isolate ofF. solani was capable of colonizing and invading the chorion of the eggs under certain humidity and temperature conditions and cause the death of the embryos.  相似文献   

5.
Purified glucoamylase (GA) from Fusarium solani was chemically modified by cross-linking with aniline hydrochloride in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) for 1 [aniline-coupled glucoamylase-1 (ACG-1)], 7 (ACG-7), and 13 min (ACG-13). The aniline coupling of GA had a profound enhancing effect on temperature, pH optima, and pK a’s of active site residues. The specificity constants (K cat/K m) of native, ACG-1, ACG-7, and ACG-13 were 136, 244, 262, and 208 at 55°C for starch, respectively. The enthalpy of activation (ΔH*) and free energy of activation (ΔG*) for soluble starch hydrolysis were lower for the chemically modified forms compared to native GA. Proteolysis of ACGs by α-chymotrypsin and subtilisin resulted in activation.  相似文献   

6.
Fusarium venenatum A3/5 was transformed using the Aspergillus niger expression plasmid, pIGF, in which the coding sequence for the F. solani f. sp. pisi cutinase gene had been inserted in frame, with a KEX2 cleavage site, with the truncated A. niger glucoamylase gene under control of the A. niger glucoamylase promoter. The transformant produced up to 21 U cutinase l−1 in minimal medium containing glucose or starch as the primary carbon source. Glucoamylase (165 U l−1 or 8 mg l−1) was also produced. Both the transformant and the parent strain produced cutinase in medium containing cutin.  相似文献   

7.
Fumonisins were readily produced in cultures of Fusarium moniliforme using a defined liquid medium. Addition of 200 mg of d3-methyl L-methionine to 100-ml cultures of F. moniliforme gave increased overall yields and high levels of deuterium (2H) incorporation into fumonisin B1. Approximately 90% of the resulting fumonisin B1 contained 6 deuterium atoms, while 9% of the product contained 3 deuterium atoms. Deuterium was shown to be incorporated exclusively in the methyl groups of the fumonisin backbone. The addition of as little as 5 mg of labeled methionine stimulated fumonisin production, but only about 5% of the fumonisin produced contained 3 deuterium atoms.Abbreviations ELEM equine leukoencephalomalacia Mention of companies or products by name does not imply their endorsement by the US Department of Agriculture over others not cited.  相似文献   

8.
A lectin from the mycelial extract of an endophytic strain of Fusarium solani was purified. Its hemagglutinating activity was inhibited by glycoproteins possessing N-linked as well as O-linked glycans. The thermodynamics and kinetics of binding of glycans and glycoproteins to F. solani lectin was studied using surface plasmon resonance. The lectin showed high affinity for asialofetuin, asialomucin, asialofibrinogen, and thyroglobulin; and comparatively low affinity for mucin, fetuin, fibrinogen, and holotransferrin. Glycoproteins showed several fold higher affinity than their corresponding glycans with significant contribution from enthalpy and positive entropy, suggesting the involvement of non-polar protein-protein interaction. Moreover, the higher affinity of the glycoproteins was due to their faster association rates and low activation energy.  相似文献   

9.
A shift from cell-surface hydrophobicity to hydrophilicity was experimentally induced in the benthic hydrophobic cyanobacterium Phormidium sp. strain J-1, by mechanical shearing, chloramphenicol, and proteolytic treatment after preincubation with sodium dodecyl sulfate (SDS). Treatment with SDS alone, while releasing large amounts of protein and carbohydrates from the cell wall, did not affect cell surface hydrophobicity.Ultrastructural analysis showed the cells, to be enveloped by a double-layered minicapsule. Treatments affecting cellsurface hydrophobicity also caused changes in capsular components. A model, describing cell-surface structure, composition and properties in Phormidium J-1, was constructed by correlating ultrastructural data with surface properties.Abbreviations SDS Sodium dodecyl sulfate - DCMU 3(3,4-dichlorophenyl)-1,1-dimethylurea This paper is contributed in honor of Prof. G. Drews on the occasion of his sixtieth birthday  相似文献   

10.
Experiments were established in field microplots to examine the association between Heterodera glycines and the blue form of Fusarium solani in sudden death syndrome of soybean (SDS). Foliar disease symptoms occurred on more plants per plot, appeared 3 to 7 days earlier, and were more severe on plants grown in plots infested with F. solani + H. glycines than on those inoculated with F. solani only. Yields were suppressed only in treatments that included the nematode. Numbers of H. glycines cysts and second-stage juveniles were significantly lower in plots infested with F. solani + H. glycines than with the nematode alone. Fusarium solani was able to infect cysts and eggs.  相似文献   

11.
In previous greenhouse and laboratory studies, citrus seedlings infested with the citrus nematode Tylenchulus semipenetrans and later inoculated with the fungus Phylophthora nicotianae grew larger and contained less fungal protein in root tissues than plants infected by only the fungus, demonstrating antagonism of the nematode to the fungus. In this study, we determined whether eggs of the citrus nematode T. semipenetrans and root-knot nematode Meloidogyne arenaria affected mycelial growth of P. nicotianae and Fusarium solani in vitro. Approximately 35,000 live or heat-killed (60°C, 10 minutes) eggs of each nematode species were surface-sterilized with cupric sulfate, mercuric chloride, and streptomycin sulfate and placed in 5-pl drops onto the center of nutrient agar plates. Nutrient agar plugs from actively growing colonies of P. nicotianae or F. solani were placed on top of the eggs for 48 hours after which fungal colony growth was determined. Live citrus nematode eggs suppressed mycelial growth of P. nicotianae and F. solani (P ≤ 0.05) compared to heat-killed eggs and water controls. Reaction of the fungi to heat-killed eggs was variable. Root-knot nematode eggs had no effect on either P. nicotianae or F. solani mycelial growth. The experiment demonstrated a species-specific, direct effect of the eggs of the citrus nematode on P, nicotianae and F. solani.  相似文献   

12.
Fusarium root rot (Fusarium spp.) is one of the most important seedling diseases of coneflower (Echinacea spp.) in Alberta greenhouses. Effects of microbial antagonists (Trichoderma spp.) and fungicides, including difenoconazole, fludioxonil, and a mixture of fludioxonil, metalaxyl and difenoconazole, on the management of this disease, were investigated in Alberta. Twenty Trichoderma isolates demonstrated antagonistic activity to Fusarium in agar plate bioassays, with inhibition rates ranging from 44 to 65%. Some Trichoderma isolates significantly ( p < 0.05) reduced disease incidence and severity on seedlings in greenhouse experiments. An in vitro bioassay indicated that difenoconazole and the mixture equally inhibited the growth of both Fusarium and Trichoderma, but, while fludioxonil strongly inhibited the growth of Fusarium, it had little effect on Trichoderma, according to the dose--response models developed ( p < 0.01, R2= 0.902-0.998). Two Trichoderma isolates, T1 and T13 were applied singly or in combination with a low rate of fludioxonil in greenhouse evaluations. The results suggested that fludioxonil and Trichoderma could be integrated into a disease management program for fusarium root rot in coneflower.  相似文献   

13.
This study was focused on the role of two types of diametrically different carbon sources, n-alkanes represented by a mixture of dodecane–hexadecane, and phenol on modification of the cell surface hydrophobicity. Capabilities of using either solely hydrocarbons or hydrocarbons in the mixture with phenol as well as phenol itself by yeast species Candida maltosa, Yarrowia lipolytica and Pichia guilliermondii were investigated. Studies were complemented by cell biomass formation measurements. The corresponding cell surface hydrophobicity was assessed by microbial adhesion to the hydrocarbon test (MATH). Degradation of phenol was examined using GC-SPE technique, whereas hydrocarbons were extracted prior to gravimetric determination. Results obtained indicated that the hydrophobic or hydrophilic nature of the carbon source had significant influence on the cell surface hydrophobicity. Although the results differed for some individual yeast strains, the generalization can be made that there is the correlation between the best hydrocarbon and phenol degradation and corresponding cell wall properties of the yeast examined.  相似文献   

14.
To test the effect of seed treatment with fungicides on the development of mycorrhizal fungi, bean seeds were treated with fungicide dry or vehicled in the organic solvents, ethanol or dichloromethane and then planted in soil inoculated with the mycorrhizal fungus Glomus macrocarpum and/or the plant pathogenic fungus Fusarium solani. Measurements were made at 4 day intervals, to evaluate the location and extent of colonization of either Glomus macrocarpum or Fusarium solani in the root system. Most combinations of fungicide-solvent had little effect on the extent of colonization by each fungus individually. However, when both fungi were inoculated together, symptoms of F. solani were seen only in the tips of roots which indicate that the mycorrhizal fungus was able to limit the occurrence of the pathogenic fungus.  相似文献   

15.
Fusarium wilt is an economically important disease in carnation and tomato plants. The use of suppressive plant growth media has become an alternative method for plant disease control due to the lack of effective chemical control measures. Plant disease suppressiveness is sustained only in plant growth media with an adequate organic matter (OM) composition. Carbohydrate polymers are the most important sources of carbon nutrient for microbial community in these media, mainly consisting of cellulose and hemicellulose. This determines microbial activity, biomass and selects microbial communities in plant growth media, which are reported factors associated with Fusarium wilt suppressiveness.This work determined OM carbon functional groups using Single Pulse Magic Angle Spinning 13C-Nuclear Magnetic Resonance (SP-MAS 13C-NMR) in three plant growth media with different suppressiveness levels to Fusarium wilt in two crops, carnation and tomato. We propose that the critical role of OM to sustain naturally occurring suppressiveness in those media is not related with cellulose reserve. This could be explained because cellulose protected by lignin encrustation is not available to microbial degradation, meaning that cellulose availability is critical to sustenance of microorganism-mediated biological control. However, the hemicellulose relative abundance (peak 175 ppm) was associated to Fusarium wilt suppression level in plant growth media studied.Carbon source availability in OM was related to microbial biomass and econutritional group population densities involved in biocontrol. For these composts, Bacillus spp., oligotrophic and cellulolytic actinomycetes, and oligotrophic actinomycetes/oligotrophic bacteria and cellulolytic actinomycetes/cellulolytic bacteria ratios were indicated as microbial populations potentially involved in suppression.  相似文献   

16.
Fusarium species are hyaline moulds belonging to the hyalohyphomycosis group that are usually found in the soil and plants. This organism has emerged as a cause of disseminated invasive disease. The correlation between in vitro value and clinical efficacy is low and many patients remain unresponsive to treatment despite in vitro susceptibility. We determined growth control for Fusarium solani using the BioCell-Tracer system that measures the growth rate of a single fungal hypha, and the effect of different concentrations of amphotericin B and itraconazole. The MIC for these two drugs was also determined by a broth microdilution technique, using RPMI 1640. Different MICs for amphotericin B were obtained by the two different methods. This paper describes a case of infection due to Fusarium solani in an allogeneic bone marrow transplanted patient, the microbiological diagnostic, antifungal susceptibility tests for conidia and hypha and clinical correlation.  相似文献   

17.
Fifty commercial corn hybrids with different endosperm characteristics, vegetative cycle length and cross class grown in the same geographical area (Cordoba Province, Argentina) were analysed for fumonisin accumulation. All hybrids analysed showed fumonisin B1 and B2 contamination ranging from 185 to 27,050 ng/g for FB1 and from 40 to 9950 ng/g for FB2. Although most of the hybrids analysed had flint-type endosperm, two hybrids with dent-type endosperm (e.g. Prozea 10 and AX 746) showed the highest level of fumonisin (37,000 ng/g) and more FB2 than FB1 (FB2/FB1 ratio 2.42), respectively. There was no correlation between fumonisin concentration and length of the vegetative cycle. Among 18 hybrids examined for Fusarium species contamination there was also no correlation between fumonisin contamination and the level of infection with Fusarium species (Section Liseola). Eighteen hybrids showed fumonisin levels lower than 1000 ng/g. This result suggests that there is some possibility of selecting hybrids resistant or less susceptible to fumonisin and Fusarium contamination.  相似文献   

18.
Damping-off of tomato caused by Rhizoctonia solani was controlled in a pot test using the biological agent, Bacillus subtilis RB14-C, and the chemical pesticide, Flutolanil. The co-utilization of B. subtilis RB14-C, and Flutolanil decreased the amount of Flutolanil used from 375 g/pot when Flutolanil was used alone to 94 g/pot, while exerting the same effect of reducing disease occurrence.  相似文献   

19.
The purpose of this research was to determine whetherBacillus subtilis,nonpathogenicFusarium oxysporum,and/orTrichoderma harzianum,applied alone or in combination to chickpea (Cicer arietinumL.) cultivars ‘ICCV 4’ and ‘PV 61’ differing in their levels of resistance to Fusarium wilt, could effectively suppress disease caused by the highly virulent race 5 ofFusarium oxysporumf. sp.ciceris.Seeds of both cultivars were sown in soil amended with the three microbial antagonists, alone or in combination, and 7 days later seedlings were transplanted into soil infested with the pathogen. All three antagonistic microorganisms effectively colonized the roots of both chickpea cultivars, whether alone or in combination, and significantly suppressed Fusarium wilt development. In comparison with the control, the incubation period for the disease was delayed on average about 3 days and the final disease severity index and standardized area under the disease progress curve were reduced significantly between 14 and 33% and 16 and 42%, respectively, by all three microbial antagonists. Final disease incidence only was reduced byB. subtilis(18–25%) or nonpathogenicF. oxysporum(18%). The extent of disease suppression was higher and more consistent in ‘PV 61’ than in ‘ICCV 4’ whether colonized byB. subtilis,nonpathogenicF. oxysporum,orT. harzianum.The combination ofB. subtilis+T. harzianumwas effective in suppressing Fusarium wilt development but it did not differ significantly from treatments with either of these antagonists alone. In contrast, the combination ofB. subtilis+ nonpathogenicF. oxysporumtreatment was not effective but either antagonist alone significantly reduced disease development.  相似文献   

20.
The fungus Fusarium solani (Mart.) Sacc. was discovered as a native entomopathogen of the sugarbeet root maggot, Tetanops myopaeformis (R?der), in the Red River Valley of North Dakota during the 2004 sugarbeet production season. This is the first report of a native pathogen affecting the pupal stage of T. myopaeformis. Forty-four percent of larvae collected from a field site near St. Thomas (Pembina Co.) in northeastern North Dakota during May and June of 2004 were infected with the entomopathogen. The mean LC(50) of F. solani, assessed by multiple-dose bioassays with laboratory-reared pupae, was 1.8x10(6)conidia/ml. After isolation and confirmation of pathogenicity, a pure isolate of the fungus was deposited in the ARS Entomopathogenic Fungal Collection (ARSEF, Ithaca, NY) as ARSEF 7382. Symptoms of F. solani infection included rapid pupal tissue atrophy and failure of adults to emerge. Transverse dissections of infected pupae revealed dense hyphal growth inside puparia, thus suggesting fungal penetration and pathogenicity. Mycelia emerged from pupae after host tissues were depleted. Exposure of older pupae to lethal concentrations caused rapid mortality of developing adults inside puparia. A second, more extensive field survey was conducted during the 2005 cropping season, and F. solani infection was observed in root maggots at most locations, although at lower levels (1-10%) of prevalence than in 2004. Aberrant timing or amounts of rainfall received could have caused asynchrony between pathogen and host during the second year of the experiment.  相似文献   

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