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Fusarium Spp. (fusarium + spp)
Selected AbstractsApplication of nr-DNA ITS sequence for identification of Fusarium culmorum isolates,EPPO BULLETIN, Issue 3-4 2000P. K. Mishra Variation within the internal transcribed spacers (ITS1 and ITS2) and 5.8S ribosomal DNA region of 60 Fusarium culmorum isolates (section Discolor), representing different hosts and diverse geographical origins was examined by polymerase chain reaction (PCR), coupled with sequencing. Phylogenetic relationships of these F. culmorum isolates were estimated in relation to Fusarium spp. from this and other sections of the form-genus, using sequences available from Genbank. The amplified ITS region was approximately 570 bp long in 56 isolates and approximately 585 bp in four other isolates. The inferred phylogeny distinguished clearly four isolates supplied as F. culmorum. These isolates differed in both morphology and sequence from the remaining F. culmorum material. Sequence analysis revealed that the remaining 56 isolates were divided into three ITS types, within which the divergence was extremely low. ITS sequence comparison among the Fusarium isolates showed two major clades, one comprising sections Discolor, Sporotrichiella and Gibbosum and the other comprising Elegans, Liseola, Martiella and Roseum. These results demonstrate the use of the ITS region to resolve the identification and taxonomic problems of Fusarium spp. especially at sectional level but demonstrate the need to develop some other molecular markers for identification at the level of species or race. [source] The use of ITS DNA sequence analysis and MALDI-TOF mass spectrometry in diagnosing an infection with Fusarium proliferatumEXPERIMENTAL DERMATOLOGY, Issue 11 2008Florian Seyfarth Abstract:, Although mycoses are among the most common diseases worldwide, infections with Fusarium spp. occur only rarely. Mostly patients suffering from underlying immune deficiency are infected with this mould, resulting in a considerably decreasing prognosis. In immunocompromised patients, cutaneous manifestations are more often associated with Fusarium sp. than with Candida sp. or Aspergillus sp. We describe one patient with acute lymphoblastic leukaemia, who was first treated with chemotherapy after GMALL protocol 07/03. After relapse, the patient was successfully transplanted in second remission with a human leukocyte antigen (HLA)-matched unrelated peripheral blood stem cell graft. Ten months later, the patient died from respiratory insufficiency and recurrence of leukaemia. Previously, Aspergillus antigen was detected in blood. In the latter course, disseminated papules appeared. One of these was examined histologically and mycologically. Conventional cultural diagnostics led to the diagnosis of a fusariosis, further supported by internal transcribed spacer (ITS) sequencing and matrix assisted laser desorption/ionisation,time-of-flight mass spectrometry (MALDI-TOF) mass spectrometry, both determining the isolated strain as Fusarium proliferatum, which is a very infrequent pathogen within this genus. Our investigations underline the potential of MALDI-TOF MS based identification of Fusarium species as an innovative, time and cost efficient alternative to ITS sequencing. [source] Pathogenicity of Fusarium verticillioides and Fusarium oxysporum on Pinus nigra seedlings in northwest SpainFOREST PATHOLOGY, Issue 2 2008P. Martín-Pinto Summary Fusarium verticillioides may be responsible for causing significant damping-off damage similar to that incited by F. oxysporum on forest seedlings, resulting in considerable losses in nurseries in northwest of Spain. Traditionally, F. oxysporum has been considered the most important agent of this disease in Spanish forest nurseries. However, recent studies have showed that F. verticillioides also has been frequently isolated from diseased plants. This has increased the necessity for a more comprehensive knowledge of the behaviour and pathogenicity of both Fusarium spp. isolated from these sites. The effect of Fusarium spp. on seed germination and on seedling mortality was analysed by inoculating the fungus at seeding. The in vitro growth of the two species was studied and is discussed in relation to in vivo virulence. Both species caused a reduction in seed germination and an increase in seedling mortality. Mortality caused by F. verticillioides treatments occurred sooner than that for F. oxysporum and the growth rate of F. verticillioides was also greater. [source] Antifungal activity of fatty acids and their monoglycerides against Fusarium spp. in a laboratory mediumINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 2 2009Clelia Altieri Summary The antifungal activity of lauric, myristic and palmitic acids and their monoglycerides against fusaria was investigated. Data were modelled through a re-parameterized Gompertz equation and the Minimum Detection Time (MDT), i.e. the time (days) to attain 1 cm colony diameter, was evaluated. Lauric acid exerted a strong bioactivity against moulds; palmitic and myristic acids and their monoglycerides showed a moderate effectiveness and in a reversible manner. The results of this work could be considered quite promising; however, further investigations are proposed to validate these data in foods. [source] Consumer preferences and fungal and mycotoxin contamination of dried cassava products from GhanaINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2001Peter W. Wareing Summary Members of one hundred and twenty five households from 19 villages producing dried cassava products were interviewed in Ghana. Kokonte was the most important cassava product in 19% of the households processing it. Most kokonte was produced between January and March. Mould growth during processing or storage was a problem during June and July, which is part of the rainy season. Most producers and market traders preferred non-mouldy kokonte, although many (59%) would consume a mouldy product. There was a price premium for non-mouldy kokonte. The most commonly isolated fungi were yeasts and Cladosporium spp. (44 out of 49 samples). Other fungi isolated included Aspergillus spp. (20 samples); Penicillium spp. (15 samples) and Fusarium spp. (30 samples). Sterigmatocystin was detected in 10 samples at 0.17,1.67 mg kg,1; patulin in 4 samples at 0.55,0.85 mg kg,1; cyclopiazonic acid in 4 samples at 0.08,0.72 mg kg,1; penicillic acid in 5 samples at 0.06,0.23 mg kg,1 and tenuazonic acid in 3 samples at 0.02,0.34 mg kg,1. Mycotoxin contamination of mouldy kokonte was a potential problem; there is therefore the need to improve kokonte processing to avoid mould growth. [source] Micro-scale Systematic Sampling of Soil: Heterogeneity in Populations of Fusarium oxysporum, F. solani, F. roseum and F. moniliformeJOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2000M. C. Rodríguez-Molina Abstract The variability of Fusarium spp. density in soil was studied in a field located in Badajoz (south-western Spain). The upper 40 cm of each side of a 1 m × 1 m × 1 m pit were sampled intensively, taking soil samples from points 10 cm apart. The species isolated were F. oxysporum, F. solani, F. roseum and F. moniliforme. For all four sides of the pit population densities of F. oxysporum, F. solani and F. roseum significantly decreased with increasing soil depth and for all the four layers significant differences were detected between sides of the pit. Horizontal variability also occurred on a smaller sampling scale: when a layer of a side was sampled, densities might be significantly different between points in the layer. However, no clear trend in horizontal variability was observed for any species. These findings demonstrate that Fusarium spp. populations were heterogeneously distributed in this reduced soil volume. Zusammenfassung Die Variabilität der Dichte von Fusarium spp. im Boden wurde in einem Feld in Badajoz (Südwestspanien) untersucht. Die oberen 40 cm jeder Seite einer 1 m × 1 m × 1 m großen Grube wurden intensiv beprobt, wobei im Abstand von jeweils 10 cm Bodenproben entnommen wurden. Aus den Proben wurden F. oxysporum, F. solani, F. roseum und F. moniliforme isoliert. An allen vier Seiten der Grube nahmen die Populationsdichten von F. oxysporum, F. solani und F. roseum mit zunehmender Bodentiefe signifikant ab. Bei allen vier Schichten wurden signifikante Unterschiede zwischen den Seiten der Grube festgestellt. Bei kleinerem Beprobungsmaßstab wurde auch horizontale Variabilität festgestellt: Wenn eine Schicht einer Seite beprobt wurde, unterschieden sich die Dichten zwischen den einzelnen Punkten der Schicht teilweise signifikant. Für keine Art war jedoch eine deutliche Tendenz bei der horizontalen Variabilität feststellbar. Die Ergebnisse zeigten, daß die Populationen von Fusarium spp. in diesem kleinen Bodenvolumen heterogen verteilt waren. [source] Identity and Pathogenicity of Fungi Associated with Root and Crown Rot of Soft Red Winter Wheat Grown on the Upper Coastal Plain Land Resource Area of MississippiJOURNAL OF PHYTOPATHOLOGY, Issue 2 2000M. S. Gonzalez Seedling stand, disease severity and fungal incidence were determined from untreated ,Wakefield' soft red winter wheat planted on a Leeper silty clay loam in field tests conducted at the Mississippi Agricultural and Forestry Experiment Station, Plant Science Research Center, Mississippi State University, Starkville, Mississippi during the 1996,97 and 1997,98 growing seasons. Seedling stand was reduced by 40% each year in plots established with untreated seed. Cochliobolus sativus was the most frequently isolated fungus. Fusarium acuminatum, Fusarium equiseti and Fusarium solani were the most prevalent Fusarium spp. Seven other Fusarium spp. and 23 species of other fungal genera were isolated. Pathogenicity tests with three isolates each of C. sativus, Cochliobolus spicifer, F. acuminatum, F. solani, F. equiseti, Fusarium compactum, Embellisia chlamydospora and Microdochium bolleyi were performed in test tube culture and two isolates each of C. sativus, C. spicifer, F. acuminatum, E. chlamydospora and M. bolleyi under greenhouse conditions. In test tubes and in the greenhouse, seedlings infected with isolates of C. sativus developed seedling blight, discoloration and necrosis, primarily in seminal roots and crowns. In the greenhouse, C. sativus induced lesions on the lower leaf sheath and reduced seedling height, seedling emergence, dry and fresh weight of roots and shoots. Isolates of F. acuminatum, F. solani, F. equiseti, F. compactum, E. chlamydospora and M. bolleyi induced slight to moderate orange to light-brown discoloration of crown and seminal roots in test tubes. Cochliobolus spicifer isolates had the most pre-emergence activity, inducing black root discoloration and root pruning of wheat seedlings and reducing seedling emergence, root fresh weight and shoot dry weight. In the greenhouse, F. acuminatum reduced seedling height, seedling emergence and root and shoot dry weights. Microdochium bolleyi and E. chlamydospora reduced fresh and dry weight of roots, plant emergence and shoot dry weight. Fusarium acuminatum and C. spicifer reduced the growth rate of wheat seedlings. All fungi evaluated showed increased disease severity compared to the untreated control. The high frequency of isolation of C. sativus from crown and root tissues can be partially explained by the dry, warm conditions during the early stages of wheat seedling development in the Upper Coastal Plain Land Resource Area of Mississippi. Zusammenfassung Die Auflaufrate von Sämlingen, die Stärke des Krank-heitsbefalls sowie die Häufigkeit von Pilzarten wurden bei nicht behandelten roten Weichwinterweizen der Sorte Wakefield ermittelt, welche in einem Leeper schlammigen Tonboden an der Mississippi Agricultural & Forestry Experiment Station, Plant Science Research Center, Mississippi State University, Starkville, Mississippi in der 1996,97 und 1997,98 Saison gesät worden waren. In beiden Jahren wurde die Auflaufrate von nicht behandeltem Saatgut um 40% reduziert. Cochliobolus sativus wurde am häufigsten isoliert. Fusarium acuminatum, Fusarium equiseti und Fusarium solani waren die überwiegenden Fusarium spp. Außierdem wurden sieben weitere Fusarium spp. sowie 23 weitere Pilzarten isoliert. Pathogenitätstests mit je 3 Isolaten von C. sativus, Cochliobolus spicifer, F. acuminatum, F. solani, F. equiseti, Fusarium compactum, Embellisia chlamydospora und Microdochiumbolleyi wurden in Reagenzröhrchen durchgeführt, sowie mit je 2 Isolaten von C. sativus, C. spicifer, F. acuminatum, E. chlamydospora und M. bolleyi unter Gewächshausbedingungen. Sowohl in den Reagenzröhrchen als auch im Gewächshaus entwickelten Sämlinge, die mit C. sativus inokuliert worden waren, eine Fäule, Verfärbung sowie Nekrosis, hauptsächlich in den sekundären Wurzeln und in den Halmbasen. Unter Gewächshausbedingungen verursachte C. sativus außierdem Läsionen der unteren Blattscheide sowie eine Reduzierung des Sämlingswachstums, des Sämlingsauflaufs, des Trocken-und Frischgewichts der Wurzeln und Sprossen. Im Reagenzröhrchentest induzierten Isolate von F. acuminatum, F. solani, F. equiseti, F. compactum, E. chlamydospora und M. bolleyieine schwache bis mäßiige orange bis hell braune Verfärbung des Halmbasis und der Sekundärwurzeln. Isolate von C. spicifer besaßien die höchste Vorauflaufaktivität und induzierten eine Verschwärzung und Verkürzung der Wurzeln sowie eine Reduzierung des Sämlingsauflaufs, des Wurzelfrischgewichts sowie des Sproitrockengewichts. Unter Gewächshausbedingungen reduzierte F. acuminatum die Sämlingshöhe, die Auflaufrate sowie das Trockengewicht der Wurzeln und Sproien. Microdochium bolleyi und E. chlamydospora reduzierten das Frisch-und Trockengewicht der Wurzeln, die Auflaufrate sowie das Sproßitrockengewicht. Die Wachstumsrate der Sämlinge wurde durch F. acuminatum und C. spicifer reduziert. Alle untersuchten Pilzarten erhöhten die Befallsstärke verglichen mit der unbehandelten Kontrolle. Die hohe Isolierungsrate von C. sativus aus dem Halmbasis-und Wurzelgewebe kann zum Teil dadurch erklärt werden, dass während der Frühentwicklungsphase der Sämlinge trockene und warme Wachstumsbedingungen in diesem Gebiet herrschten. [source] Effects of weather variables on grain mould of sorghum in South AfricaPLANT PATHOLOGY, Issue 2 2006G. Tarekegn Effects of weather variables of mould development on sorghum grain were studied over three consecutive seasons in South Africa. Five sorghum hybrids planted at different dates ensured developing seeds were exposed to different weather conditions. Incidence of grain mould fungi was determined at harvest by incubating seeds on 2% malt extract agar. Averages of different weather variables (maximum and minimum temperatures, maximum relative humidity, total precipitation and frequency of precipitation) were determined for all permutations of weekly time intervals for a 2-month postflowering period to identify when these variables and pathogen incidence were significantly correlated. Significant correlations were used to develop models to quantify relationships between variables. Significant positive correlations were observed between the incidence of mould fungi and weather 4,6 weeks after flowering in the shorter season hybrid cv. Buster, and 5,8 weeks after flowering in the remaining hybrids. In most hybrids, correlations between the incidence of grain mould pathogens, including Alternaria alternata, Curvularia spp. (C. lunata and C. clavata), Fusarium spp. (F. proliferatum and F. graminearum), and Drechslera sorghicola, and average minimum temperature, total rainfall and frequency of rainfall were significant (P = 0·05). In four hybrids, models showing a linear relationship between the logarithm of pathogen incidence and minimum temperature, and in one hybrid, between pathogen incidence and rainfall frequency, were developed. Depending on the hybrid, models that used minimum temperature as predictor described 60,82% of variation in the incidence of pathogens. Frequency of rainfall explained 93% of the variation in pathogen incidence in one sorghum hybrid genotype. Evaluation of the models using an independent data set yielded average prediction errors near zero, indicating that the models were acceptable. [source] Disease complex in coffee involving Meloidogyne arabicida and Fusarium oxysporumPLANT PATHOLOGY, Issue 3 2000B. Bertrand Coffee corky-root disease, also called corchosis, was first detected in 1974 in a small area of Costa Rica where the root-knot nematode Meloidogyne arabicida is the dominant species. An epidemiological study revealed a constant association between Meloidogyne spp. and Fusarium sp. in cases of corky root. No corky root appears to have been reported in association with Meloidogyne exigua, which is the prevalent root-knot nematode on coffee in Costa Rica. Fusarium spp. are often cited as components of disease complexes in association with nematodes. Combined inoculations using M. arabicida or M. exigua with Fusarium oxysporum under controlled conditions showed that only the combination with M. arabicida produced corky-root symptoms on Coffea arabica cvs Caturra or Catuai. Fusarium oxysporum alone was nonpathogenic. Meloidogyne exigua or M. arabicida alone caused galls and reduction in shoot height, but no corky-root symptoms. When cultivars susceptible and resistant to M. arabicida were studied under field conditions for 5 years, all the susceptible cultivars exhibited corky-root symptoms on 40,80% of their root systems. Cultivars that were resistant to M. arabicida but not to M. exigua showed no corky root. These observations lead to the conclusion that corky-root disease has a complex etiology, and emphasize the dominant role of M. arabicida as a predisposing agent to subsequent invasion by F. oxysporum. Consequently, genetic resistance to M. arabicida appears to provide an effective strategy against the disease. [source] Studies on Colletotrichum acutatum and Greeneria uvicola: Two fungi associated with bunch rot of grapes in sub-tropical AustraliaAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 1 2007CHRISTOPHER C. STEEL Abstract Vineyards in the Hunter Valley and Hastings Valley (sub-tropical NSW) were examined by unaided eye for visible symptoms of bunch rot diseases at berry maturity in 2003 (for a total of five varieties over seven vineyards). Grey mould (Botrytis cinerea) was evident in three vineyards, and ripe rot (Colletotrichum acutatum) was evident in four of those seven vineyards surveyed. Other bunch rots at six of the vineyards could not be readily identified by visual inspection. The incidence of fungi on grapevine reproductive structures (and potentially bunch-rot fungi) was then recorded for a Cabernet Sauvignon vineyard in the Hastings Valley during the 2004/5 and 2005/6 growing seasons, and outcomes are reported here in some detail. By berry maturity, C. acutatum and Greeneria uvicola (bitter rot) were the predominant pathogens isolated from those structures, and constitute the first such report of bitter rot fungi on wine grapes in Australia. Indeed, the frequency of latent infection by C. acutatum and G. uvicola increased with berry development during the growing season. Other fungi isolated included Alternaria spp., Botryosphaeria spp., Cladosporium spp., Epicoccum sp., Fusarium spp., Nigrospora spp., Pestalotia spp., Phomopsis viticola and Trichoderma spp. Isolation of B. cinerea from this vineyard was rare. Infection of various wine grape varieties in vitro with C. acutatum and G. uvicola at post veraison revealed all varieties to be susceptible over a range of temperatures (20,35oC). Based on laboratory studies, there was no infection of berries at a relative humidity (RH) < 50%, and infection diminished at 87% RH. Infection did occur if the berries were first incubated at 100% RH for 24 hours, and then transferred to an environment of lower humidity. [source] Involvement of Fusarium spp. in fungal keratitisCLINICAL MICROBIOLOGY AND INFECTION, Issue 9 2004I. Dóczi Abstract Members of the filamentous fungal genus Fusarium are among the agents most frequently causing keratomycosis in humans. Fusarium keratitis is most common among agricultural workers in geographical regions with hot, humid, tropical or semi-tropical climates, but can occur more rarely in countries with temperate climates, such as Hungary. Keratitis is usually treated with a topical antifungal agent, sometimes in combination with sub-conjunctival injections and/or antimycotic agents, but therapeutic keratoplasty may be needed for patients whose corneal infection does not resolve. Early and accurate diagnosis, coupled with appropriate antifungal therapy, is crucial for improving the chances of complete recovery. [source] | |||||||||||||||||||||||||