• 한국유기농업학회지
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• 제28권1호
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• pp.95-108
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• 2020

To develop an environment-friendly fungicide for controlling tomato wilt diseases, antifungal active substance was isolated Rheum australe D. Don roots against Fusarium oxysporum f. sp. lycopersici, a pathogen of tomato wilt, in this study. Methanol extract obtained from Rheum australe roots was successively fractionated with hexane, chloroform, ethyl acetate, butanol and water. The ethyl acetate fraction, which showed the highest antifungal activity, was separated by column chromatography, and 60 subfractions were obtained. The 60 subfractions were anlayzed for antifungal activities by bioassay. The active compound was identified as 5-[(E)-2- (3-hydroxy-4-methoxyphenyl)ethenyl]benzene-1,3-diol (rhapontigenin) by NMR and GC-MS analysis. As a result of testing antifungal activity of rhapontigenin against Fusarium oxysporum, EC₅₀ of rhapontigenin was showed strong antifungal activity at 7.48 mg/L. Therefore, this study showed that the Rheum australe roots extract can be a potential candidate which is a environment-friendly fungicide against Fusarium oxysporum.

• 한국식물병리학회지
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• 제10권4호
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• pp.314-318
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• 1994

Incidence of stem rot on carnation (Dianthus caryophyllus L.) ranged 11 to 29% in Namwon and Chongup area during the growing seasons from 1993 to 1994. Among 129 isolates from carnations in Namwon, 77 isolates were identified as Rhizoctonia solani, 38 isolates were Fusarium oxysporum and 14 isolates were not identified. Among 169 isolates in Chongup, 19 isolates were identified as R. solani, 106 isolates as F. oxysporum and 44 isolates were not identified. Among 77 isolates of R. solani isolated from the specimens of Namwon, 52 isolates were classified as anastomosis group AG 2-2 by anastomosis test, 14 isolates as AG 2-1 and 11 isolates as AG 4. Among 19 isolates from specimens of Chongup, 14 isolates were classified as anastomosis group AG 2-2 and 5 isolates as AG 4. Pathogenicity tests revealed that isolates of F. oxysporum and R.solani AG 2-2 were highly virulent and isolates of R.solani AG 2-1 and AG 4 were mildly virulent.

• 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.

• 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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• 제12권2호
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• pp.137-141
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• 1996

오이에서 분리한 비병원성 Fusarium oxysporum 균주 4-1은 온실에서 오이에서 선접종하였을 때 덩굴쪼김병에 안정적인 방제효과를 보여 세 번의 시험에서 그 방제가가 67~100%에 달하였다. 이 균주는 접종후 90일에도 오이 뿌리에서 높은 빈도로 재분리 되었으며 g 토양당 분생포자 농도가 10\ulcorner개 이상의 높은 농도로 접종하였을 때는 뿌리의 갈변현상을 초래하였다. 1993년부터 1995년에 걸친 세 번의 포장시험에서 이 균주는 오이덩굴쪼김병의 발생을 무처리 발병율 56%, 11%, 35%에 비해 18%, 1%, 8%로 각각 억제하였다.

• 한국식물병리학회지
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• 제12권4호
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• pp.471-475
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• 1996

콩나물의 생육부진과 부패는 콩나물 재배에 중요한 제한요인이다. 콩나물 부패 병원 진균으로 Fusarium moniliforme, F. oxysporum과 F. solani를 분리 동정하였다. 이들은 종자 발아 후 3∼5일이 지난후 콩나물의 중간 이하에 연한 갈색의 외부 병징을 만들며 발아 후 6∼7일 경에 병징이 더욱 진전하여 진한 갈색의 외부 병징을 나타냄으로써 콩나물에 대한 병원성이 인정되었다. Hand-section과 microtome-section에 의한 병태 조직학적 관찰에서 F. oxysporum 접종 후 4일이 경과하여 초기 병징을 보인 조직에서 균사가 피층, 세포간극, 목부, 사부, 수에 분포하고 있음이 관찰되었다.

• The Plant Pathology Journal
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• 제36권6호
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• pp.637-642
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• 2020

Fusarium wilt in tobacco caused by the fungus Fusarium oxysporum f. sp. nicotianae is a disease-management challenge worldwide, as there are few effective and environmentally benign chemical agents for its control. This challenge results in substantial losses in both the quality and yield of tobacco products. Based on an in vitro analysis of the effects of different phenylpropanoid intermediates, we found that the early intermediates trans-cinnamic acid and para-coumaric acid effectively inhibit the mycelial growth of F. oxysporum f. sp. nicotianae strain FW316F, whereas the downstream intermediates quercetin and caffeic acid exhibit no fungicidal properties. Therefore, our in vitro screen suggests that trans-cinnamic acid and para-coumaric acid are promising chemical agents and natural lead compounds for the suppression of F. oxysporum f. sp. nicotianae growth.

• 한국식물병리학회지
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• 제12권2호
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• pp.245-250
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• 1996

식물병원균 Botrytis cinerea와 Fusarium oxysporum에 대한 생물학적 방제의 기초자료를 얻기 위하여 살충성 진균 Beauveria bassiana의 식물병원균에 대한 균사성장저해, 포자발아 억제, 균사와 포자의 형태변화 등의 효과를 살펴보았다. 평판배지 상에서 두 식물병원균의 균사생장이 저해되었으며, 저해효과는 배지종류에 따라 달랐는데 B. cinerea의 경우 PDA배지에서 가장 크게 저해되었으며 F. oxysporum의 경우에는 TSA배지에서 가장 크게 저해되었다. B. bassiana는 $25^{\circ}C$에서 6일간 배양했을 때 F. oxysporum에 대한 항균력이 가장 높았으며 동시에 최대의 균체량을 생산하였다. 또한 B. bassiana의 배양여액을 식물병원균에 30% 농도로 첨가하여 배양했을 때 식물병원균의 포자 발아율은 B. cinerea, F. oxysporum에서 각각 30%(control: 88.2%), 10.0%(control: 78.6%)로 낮아졌으며 발아 개시 시간도 4~8시간 지연되었다. 현미경을 통한 미세구조관찰에서는 10%의 B. bassiana배양여액을 첨가했을 때 F. oxysporum의 포자 크기가 1/2~1/3으로 줄어들었으며 균사와 격막의 형태도 비정상적으로 변하여 균사외막과 격막-격막 사이의 구분이 불명확해졌다.

• 한국식물병리학회지
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• 제14권6호
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• pp.583-588
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• 1998

This study was conducted to investigate the potential of nitrate-nonutilizing mutants (nit mutants) in ecological studies of Fusarium disease of strawberry. Nit mutants of Fusarium oxysporum from strawberry were easily formed on chlorate-containing media. Nit mutants were assigned to three phenotypic classes, nit1, nit3, and NitM, on the basis of their growth on media containing one of the following five different nitrogen sources ; nitrate, nitrite, hypoxanthine, ammonium and uric acid. Frequency of nit mutation and proportion of three phenotypes of nit mutants depended on the isolate. Mutation rate was 45.6% and ranged from 15.0% to 95.0%. The frequency of nit1 mutants was higher than that of nit3 or NitM. The complementary reaction between nit1 and NitM was higher than that of other combination. There has been no complementary response observed between nit3 and nit3. The nit mutants showed similar growth pattern as the that of wild type isolate on potato sucrose agar and potato sucrose liquid media. Most of the mutants retained pathogenicity, and maintained their phenotypes even after two year preservation through subculture on slanted PSA at room temperature. Nit mutants were selctively isolated from infested soil and infected plants on the selective medium (MMCPA) containing potassium chlorate with their original phenotypes, while naturally occurring isolates of Fusarium oxysporum were not grow on the medium. On the contrary, nit mutants showed very slight growth on the medium (MMPA) containing nitrate as a sole nitrogen source, and therefore could be distinguished from wild type isolate.

• 한국균학회지
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• 제51권1호
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• pp.51-56
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• 2023

황칠나무는 두릅나무과에 속하는 난대성 상록활엽수로 우리나라 제주도, 보길도, 거문도, 거제도, 완도, 해남 등에 분포한다. 2021년 6월 전라남도 나주에서 황칠나무 유묘의 지제부가 갈변하고 잘록해지는 뿌리썩음병을 국내 최초로 발견하였다. 황칠나무 뿌리썩음병균을 분리 및 동정하기 위해, 유묘의 병든 조직에서 3개의 균주를 분리하였고, PDA 배지에서 형태적, 균학적 특성 조사한 결과 Fusarium oxysporum으로 동정되었다. Internal transcribed spacer (ITS) 및 translation elongation factor 1-α (EF1-α) 염기서열을 통한 분자계통학적 분석을 수행하여 한국의 황칠나무 뿌리썩음병균은 F. oxysporum임을 확인하였다. 병원성 테스트를 위해 유묘의 뿌리를 분생포자 현탁액에 침지하여 정식하였고, 접종 20일 후 처리구에서 뿌리썩음 및 지제부의 갈변 증상을 확인하였다. 본 연구는 한국의 황칠나무 유묘에서 뿌리썩음병균 F. oxysporum의 첫 보고이다.