• 한국균학회지
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• 제51권4호
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• pp.397-403
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• 2023

Wilt symptoms were observed in basil (Ocimum basilicum) plants grown in a vinyl greenhouse located in Gokseong, Korea, during crop disease surveys conducted in August 2022. The symptoms appeared as wilting of the plants and brown to dark brown longitudinal streaks on the stems at or above the soil line. The disease incidence among the plants in the vinyl greenhouse was 5-20%. Six isolates of Fusarium sp. were obtained from stem lesions and identified as Fusarium oxysporum species complex based on their morphological characteristics. Among the isolates, two were used for phylogenetic analysis and pathogenicity test. Phylogenetic analysis revealed that these isolates belonged to F. oxysporum. Pathogenicity of the isolates was confirmed through artificial inoculation test. The symptoms induced by the isolates were similar to those observed in basil plants in the investigated vinyl greenhouse. This is the first report of F. oxysporum causing Fusarium wilt in basil in Korea.

• 한국식물병리학회지
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• 제14권2호
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• pp.188-190
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• 1998

Fusarium wilt of lisianthus occurred severely throughout all cultivation areas, especially in alpoine areas during summer season and the disease incidence was 5 to 30 percent in Korea. The major symptoms of the disease were wilt with chlorosis and water deficiency, stunted plants and scorched leaves. Severe symptoms appeared just after high temperature period around late August in Daekwallyong area. Whit and pale red colored mycelia were developed on stems of infected plants near the soil surface. The causal organism of Fusarium wilt of lisianthus was isolated and identified as Fusarium oxysporum f. sp. eustomae on the basis of pathogenic and cultural characteristics. The causal organism was reisolated from all infected and inoculated stems of plants. This is the first report referring to F. oxysporum f. sp. eustomae of lisianthus in Korea.

• 한국유기농업학회지
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• 제12권2호
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• pp.183-196
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• 2004

This study was carried out to screen and select the effects of antifungal bacterial strains which inhibit the growth of plant pathogen, Fusarium oxysporum(fusarium wilt) occurred in carnation plants in greenhouse. We isolated an effective bacterial strains and investigated into the antifungal activity of the antagonistic microorganism and it's identification. Twenty bacterial strains which strongly inhibited Fusarium oxysporum were isolated from roots of carnation plants and the soil in greenhouse, and the best antifungal bacteria designated as C121, was finally selected. Antagonistic bacterial strain, C121 was identified to be the genus Bacillus sp. based on the morphological, biochemical and cultural characterizations. The Bacillus sp. C121 showed 58.1% of antifungal activity against the growth of Fusarium oxysporum. By the bacterialization of the cultural broth and the heat bacterialization culture filtrate of it, Bacillus sp. C121 was shown 92.1% and 21.0% of antifungal activity, respectively.

• The Plant Pathology Journal
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• 제25권3호
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• pp.256-262
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• 2009

The potential of. nonpathogenic Fusarium oxysporum strain Avr5, either alone or in combination with chitosan and Bion, for inducing defense reaction in tomato plants inoculated with F. oxysporum f. sp lycopersici, was studied in vitro and glasshouse conditions. Application Bion at concentration of 5, 50, 100 and $500{\mu}g$/ml, and the highest concentration of chitosan reduced in vitro growth of the pathogen. Nonpathogenic F. oxysporum Avr5 reduced the disease severity of Fusarium wilt of tomato in split plants, significantly. Bion and chitosan applied on tomato seedlings at concentration $100{\mu}g$ a.i./plant; 15, 10 and 5 days before inoculation of pathogen. All treatments significantly reduced disease severity of Fusarium wilt of tomato relative to the infected control. The biggest disease reduction and increasing tomato growth belong to combination of nonpathogenic Fusarium and Bion. Growth rate of shoot and root markedly inhibited in tomato plants in response to tomato Fusarium wilt as compared with healthy control. These results suggest that reduction in disease incidence and promotion in growth parameters in tomato plants inoculated with nonpathogenic Fusarium and sprayed with elicitors could be related to the synergistic and cooperative effect between them, which lead to the induction and regulation of disease resistance. Combination of elicitors and non-pathogenic Fusarium synergistically inhibit the growth of pathogen and provide the first experimental support to the hypothesis that such synergy can contribute to enhanced fungal resistance in tomato. This chemical could provide a new approach for suppression of tomato Fusarium wilt, but its practical use needs further investigation.

• 한국유기농업학회지
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• 제12권1호
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• pp.101-114
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• 2004

This study was carried out to clarify the effects of antagonistic microorganism, Bacillus sp. JC181 isolated from the greenhouse soil grown cucumber plants on the growth inhibition of plant pathogen, fusarium wilt (Fusarium oxysporum) occurred in cucumber plants in greenhouse. Antagonistic bacterial strains were isolated and were investigated into the antifungal activity of the antagonistic microorganism against fusarium wilt. Screened fourteen bacterial strains which strongly inhibited F. oxysporum were isolated from thc greenhouse soil grown cucumber plants, and the best antagonistic bacterial strain designated as JC181, was finally selected. Antagonistic bacterial strain JC181 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. JC181 showed 58.2% of antifungal activity against the plant pathogen growth of F. oxysporum. By the bacterialization of culture broth and heated filtrates of culture broth, Bacterial strain, Bacillus sp. JC181. showed 91.2% and 260% of antifungal activity against F. oxysporum, respectivrly.

• 한국식물병리학회지
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• 제14권2호
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• pp.145-149
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• 1998

Four nonpathogenic isolates of Fusarium oxysporum isolated from spinach showed suppressive effect on the occurrence of the Fusarium wilt of spinach caused by F. oxysporum f. sp. sprinaciae, among which NF01 controlled the disease most effectively. And NF01 was not pathogenic to tomato, cucumber, radish and spinach. This isolate was further tested for the biological control of the disease. The isolate was not inhibitory to the growth of the pathogen on potato sucrose agar medium, however the Fusarium wilt disease occurred less by drenching spore suspension of the nonpathogenic isolate. The control effect of the isolate was higher at lower inoculum level of the pathogen than at the higher inoculum level, and in the pretreatments than the simultaneous treatment of the isolate with the pathogen inoculation. The nit mutants of the isolate were easily formed on chlorate containing media, and was reisolated selectively as nit mutant from infected soil and plants. The reisolation rate of the isolate as opposed to pathogen was high at preinoculated soil and plants relative to the simultaneous inoculation of the isolate with the pathogen.

• Mycobiology
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• 제43권2호
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• pp.174-178
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• 2015

Fusarium wilt of zucchini in Jeonju, Korea, was first noticed in May 2013. Symptoms included wilting of the foliage, drying and withering of older leaves, and stunting of plants. Infected plants eventually died during growth. Based on morphological characteristics and phylogenetic analyses of the molecular markers (internal transcribed spacer rDNA and translation elongation factor $1{\alpha}$), the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was demonstrated via artificial inoculation, and it satisfied Koch's postulates. To our knowledge, this is the first report of F. oxysporum causing wilt of zucchini in Korea.

• 한국식물병리학회지
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• 제10권4호
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• pp.325-332
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• 1994

In order to find out formulation and effect of soil amendment on Fusarium wilt of sesame caused by Fusarium oxysporum f. sp. vasinfectum, the study was conducted during the last two years of 1992 to 1993. Among 14 chemicals (1%, w/w) added to soil including CaO individually, Al2(SO4)3, Alum, and CaO suppressed mycelial growth and conidial germination of F.oxysporum f. sp. vasinfectum. CaCl2 suppressed mycelial growth only, while glycerine, KCl, K2 HPO4, and triple superphosphate suppressed conidial germination. Suppression rate was ranged from 21 to 100% on mycelial growth. The 8 chemicals were finally selected. Among the 4 organic compounds, composted pine bark showed definite suppression on mycelial growth and conidial germination of the fungus, whereas milled alfalfa leaves was only effective on conidial germination of Fusarium wilt pathogen. The antagonist Trichoderma harzianum grew well in the soil medium amended with the composted pine bark and chemicals mixture (CPM) amendment (1%, w/w) and suppressed mycelial growth of the fungus effectively. In pot test, Fusarium wilt of sesame was completely controlled by CPM amendment.

• 한국유기농업학회지
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• 제11권4호
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• pp.61-74
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• 2003

This study was conducted to screen the antagonistic bacteria which inhibit the growth of plant pathogen, fusarium wilt(Fusarium oxysporum) occurred in tomato plants in greenhouse. We isolated an effective bacterial strains and investigated into the antifungal activity of the antagonistic microorganism and it’s identification. Ten bacterial strains which strongly inhibited Fusarium oxysporum were isolated from the nature, and the best antagonistic bacterial strain designated as KC175, was selected. The antagonistic strain KC175 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. The Bacillus sp. KC175 showed 58.2% of antifungal activity against the growth of Fusarium oxysporum. By the bacterialization of the culture broth and the heat bacterialization culture filtrate of it, Bacillus sp. KC175 showed 91% and 18% of antifungal activity, respectively.

• The Plant Pathology Journal
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• 제27권4호
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• pp.390-395
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• 2011

Fusarium wilt caused by Fusarium oxysporum has become a serious problem world-wide and relies heavily on chemical fungicides. We selected Pseudomonas sp. NJ134 to develop an effective biocontrol strategy. This strain shows strong antagonistic activity against F. oxysporum. Biochemical analyses of ethyl-acetate extracts of NJ134 culture filtrates showed that 2,4-diacetylphloroglucinol (DAPG) was the major compound inhibiting in vitro growth of F. oxysporum. DAPG production was greatly enhanced in the NJ134 strain by adding mannitol to the growth media, and in vitro antagonistic activity against F. oxysporum increased. Bioformulations developed from growth of NJ134 in sterile bean media with mannitol as the carbon source under plastic bags resulted in effective biocontrol efficacy against Fusarium wilt. The efficacy of the bioformulated product depended on the carbon source and dose. Mannitol amendment in the bean-based formulation showed strong effective biocontrol against tomato Fusarium wilt through increased DAPG levels and a higher cell density compared to that in a glucose-amended formulation. These results suggest that this bioformulated product could be a new effective biocontrol system to control Fusarium wilt in the field.