• Mycobiology
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• 제34권2호
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• pp.45-55
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• 2006

Although Fursarium oxysporum causes diseases in economically important plant hosts, identification of F. oxysporum formae speciales has been difficult due to confusing phenotypic classification systems. To resolve these complexity, we evaluated genetic relationship of nine formae speciales of F. oxysporum with random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), and translation elongation factor-l alpha ($EF-1{\alpha}$) gene. In addition, the correlation between mycotoxin content of fusaric acid and isolates based on molecular marker data was evaluated using the modified Mantel's test. According to these result, these fusaric acid-producing strains could not identify clearly, and independent of geographic locations and host specificities. However, in the identification of F. oxysporum formae speciales, especially, AFLP analysis showed a higher discriminatory power than that of a the RAPD and $EF-1{\alpha}$ analyses, all three techniques were able to detect genetic variability among F. oxysporum formae speciales in this study.

• The Plant Pathology Journal
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• 제35권4호
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• pp.301-312
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• 2019

Sorghum is the fifth most important cereal worldwide, spreading from Africa throughout the world. It is particularly important in the semi-arid tropics due to its drought tolerance, and when cultivated in Southeast Asia commonly occurs as a second crop during the dry season. We recovered Fusarium from sorghum in Thailand and found F. proliferatum, F. thapsinum and F. verticillioides most frequently, and intermittent isolates of F. sacchari and F. beomiforme. The relatively high frequencies of F. proliferatum and F. verticillioides, suggest mycotoxin contamination, particularly fumonisins and moniliformin, should be evaluated. Genetic variation within the three commonly recovered species was characterized with vegetative compatibility, mating type, Amplified Fragment Length Polymorphisms (AFLPs), and female fertility. Effective population number ($N_e$) was highest for F. verticillioides and lowest for F. thapsinum with values based on mating type allele frequencies higher than those based on female fertility. Based on AFLP genetic variation, the F. thapsinum populations were the most closely related, the F. verticillioides populations were the most distantly related, and the F. proliferatum populations were in an intermediate position. The genetic variation observed could result if F. thapsinum is introduced primarily with seed, while F. proliferatum and F. verticillioides could arrive with seed or be carried over from previous crops, e.g., rice or maize, which sorghum is following. Confirmation of species transmission patterns is needed to understand the agricultural systems in which sorghum is grown in Southeast Asia, which are quite different from the systems found in Africa, Australia, India and the Americas.

• 대한수의학회지
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• 제52권1호
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• pp.45-52
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• 2012

The present study was carried out to investigate the effect of barley and barley bran contaminated with Fusarium spp on growth performance and feed efficiency of fattening and growing pigs. In experiment 1, total 48 fattening Landrace pigs were used in a fattening trial for 71 days. Pigs weighing around 75 kg were allocated into different substitution groups containing 0, 10, 20 and 30% of barley contaminated Fusarium spp. In experiment 2, total 16 growing Landrace pigs were used in a growing trial for 45 days. Pigs weighing around 29.4 kg were allocated into different substitution groups containing 0, 5, 10 and 20% of barley bran contaminated Fusarium spp. Mycotoxin concentrations of barley and barley bran contaminated with 30% Fusarium spp were 0.452 and 1.049 ppm for deoxynivalenol, 8.125 and 17.646 ppm for nivalenol and 0.023 and 0.029 ppm for zearalenone, respectively. In experiment 1, no differences were found in weight gain and feed intake between control group (0%) and 10 or 20% substitution groups, but in 30% substitution group, weight gain and feed intake were significantly lower (p < 0.05) than those in control group. After slaughtering, the extended haemorrhage of the fundus region in stomach was observed in 20 or 30% substitution groups. In experiment 2, weight gain and feed intake were not significantly different among treatment groups. After slaughtering of experimental pigs, the extended haemorrhage of the fundus region in stomach was observed in pigs fed diet with 20% substitution group. These results suggest that the feeding of diet with contaminated highly levels of Fusarium spp was negative effect on growth and feed efficiency in growing and fattening pig.

• The Plant Pathology Journal
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• 제28권3호
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• pp.259-269
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• 2012

Protein phosphatase 2A (PP2A), a family of serine/threonine protein phosphatases, plays an important role in balancing the phosphorylation status of cellular proteins for regulating diverse biological functions in eukaryotic organisms. Despite intensive studies in mammals, limited information on its role is available in filamentous fungi. Here, we investigated the functional roles of genes for a putative B' delta regulatory subunit (FgPP2AR) and a catalytic subunit (FgPP2AC) of PP2A in a filamentous ascomycete, Fusarium graminearum. Molecular characterization of an insertional mutant of this plant pathogenic fungus allowed us to identify the roles of FgPP2AR. Targeted gene replacement and complementation analyses demonstrated that the deletion of FgPP2AR, which was constitutively expressed in all growth stages, caused drastic changes in hyphal growth, conidia morphology/germination, gene expression for mycotoxin production, sexual development and pathogenicity. In particular, overproduction of aberrant cylindrical-shaped conidia is suggestive of arthroconidial induction in the ${\Delta}FgPP2AR$ strain, which has never been described in F. graminearum. In contrast, the ${\Delta}FgPP2AC$ strain was not significantly different from its wild-type progenitor in conidiation, trichothecene gene expression, and pathogenicity; however, it showed reduced hyphal growth and no perithecial formation. The double-deletion ${\Delta}FgPP2AR;{\Delta}FgPP2AC$ strain had more severe defects than single-deletion strains in all examined phenotypes. Taken together, our results indicate that both the putative regulatory and catalytic subunits of PP2A are involved in various cellular processes for fungal development in F. graminearum.

• The Plant Pathology Journal
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• 제35권4호
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• pp.313-320
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• 2019

Rye was used here to dissect molecular mechanisms of resistance to Fusarium head blight (FHB) and to go deeper with our understanding of that process in cereals. F. culmorum-damaged kernels of two lines different in their potential of resistance to FHB were analyzed using two-dimensional gel electrophoresis and mass spectrometry to identify resistance markers. The proteome profiling was accompanied by measurements of ${\alpha}-$ and ${\beta}-amylase$ activities and mycotoxin content. The proteomic studies indicated a total of 18 spots with clear differences in protein abundance between the more resistant and more susceptible rye lines after infection. Eight proteins were involved in carbohydrate metabolism of which six proteins showed a significantly higher abundance in the resistant line. The other proteins recognized here were involved in stress response and redox homeostasis. Three remaining proteins were associated with protease inhibition/resistance and lignin biosynthesis, revealing higher accumulation levels in the susceptible rye line. After inoculation, the activities of ${\alpha}-$ and ${\beta}-amylases$, higher in the susceptible line, were probably responsible for a higher level of starch decomposition after infection and a higher susceptibility to FHB. The presented results could be a good reference for further research to improve crop resistance to FHB.

• 식물병연구
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• 제26권4호
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• pp.250-255
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• 2020

페룰산 함량이 붉은곰팡이병과 곰팡이독소 저항성 곡류 육종의 선발지표가 될 수 있는지 알기 위해 밀, 보리, 벼 육성 품종 80점의 페룰산 함량을 조사하였다. 페룰산 함량은 보리 20품종이 1.66-2.77 mg/g, 밀 40품종이 0.56-1.53 mg/g이었으며 벼 20품종은 0.91-2.13 mg/g이었다. 이 중 페룰산 함량이 다른 밀과 보리 각 7품종을 선정하여 F. graminearum과 F. asiaticum 각 2균주의 붉은곰팡이병과 독소 생성량을 분석하였다. 밀 품종의 평균 병원성은 페룰산 함량이 높은 보리에 비해 유의하게 낮았고 밀 품종 간에는 상관관계가 없었다. 곰팡이독소도 병원성과 같이 페룰산 함량이 낮은 밀이 보리보다 생성량이 낮았다. 그러나 보리에서는 F. asiaticum 균주의 병원성과 독소 생성량이 페룰산 함량과 음의 상관관계를 나타내었다. 이 결과는 페룰산 함량이 밀과 보리에서 F. graminearum과 F. asiaticum에 의한 붉은곰팡이병과 독소 생성에 저항성 요인이 아님을 보여준다.

• Food Science and Biotechnology
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• 제14권6호
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• pp.823-827
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• 2005

Fusarium mycotoxin deoxynivalenol (DON) contents and its critical quality parameters were analyzed using two-rowed, six-rowed, and hulless barleys. DON content in the two-rowed Korean barleys was lower than that in the six-rowed barleys. The average DON contents of six-rowed, two-rowed, and hulless barleys were 1.35 ppm, 0.36 ppm, and 0.49 ppm, respectively. The DON content was reduced by 6.2% by sieving, by 6.0% by washing with water and by 18.1-69.8% by treatment with aqueous chemical solutions. Of the reagents investigated, aqueous sodium bicarbonate gave the greatest reduction in the barley DON level. The DON content was reduced to 62.5% of initial level after 3 days of steeping and to 23.1% after 3 days of germination. DON was not detected after steeping barley for 24 hr in 0.1M $Na_2CO_3$ solution with 0.1 % activated carbon.

• 한국식품과학회지
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• 제27권2호
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• pp.221-224
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• 1995

1992년부터 1993년 사이에 수집된 옥수수를 주재료로 한 우리나라의 사료 106 시료중 82점(77.4%)에서 fumonisin $B_{1}$이 검출되었다. 검출된 시료들의 평균 검출량은 497 ng/g이었고 최고값은 1,281 ng/g이었다.

• Mycobiology
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• 제31권4호
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• pp.183-190
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• 2003

Five cereal grains(wheat, barley, rice, maize and sorghum) were collected from three Egyptian provinces known to be grain producers(Daqahlia, Gharbia and Kafer el-Sheikh). Two species of Alternaria(A. raphani and A. tenusinae); two species of Aspergillus(A. flavus and A. niger); one species of Cunninghamella(C. elegans); one Dreschslera species(D. myakt); three Fusarium species(F. graminearum, F. moniliform and F. solani); one Rhizopus species(R. stolonifer) and two species of Penicillium(P. digitatum and P. notatum) were isolated from the grains. The densities of these fungi and their frequencies of occurrence have been investigated. All the fungal isolates were tested for the production of toxic metabolites in culture media and the percentages of toxigenic isolates were calculated. The biological assay of the toxigenic fungal isolates showed significant variations in toxigenic activity. Thin layer chromatography revealed that the most active isolate produces moniliformin in culture media. The effect of culture conditions on the production of moniliformin was studied.

• Toxicological Research
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• 제12권1호
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• pp.17-20
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• 1996

The effect of Fumonisin B1, a mycotoxin produced by Fusarium moniliforme on bacterial viruses P1 and Lambda, was investigated by the virus plaque assay. Fumonisin B1 inhibited the P1 viral multiplication in the concentration range from $100{\mu}g$/ml to $400{\mu}g$/ml. The inhibition was Fumonisin B1 concentration-dependent. Another bacterial virus Lambda multiplication was also inhibited by lower concentration of Fumonisin B1 ($10{\mu}g$/ml~$50{\mu}g$/ml). This inhibition was dependent on Fumonisin B1 and on virus-Fumonisin B1 reaction time. Sensitivity of bacteriophage Lambda to Fumonisin B1 was higher than that of P1 virus. Lambda vital DNA was treated in vitro with Fumonisin B1 at various concentration. Significant DNA fragmentation by Fumonisin 191 was observed in the agarose gel electrophoresis. Lambda viral DNA was partially digested even in the Fumonisin B1 $10{\mu}g$ and the level of its fragmentation was dependent on Fumonisin B1 amount up to $30{\mu}g$ per assay.