• 한국응용곤충학회지
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• 제20권3호
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• pp.135-145
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• 1981

전북고냉지 단경기채소단지인 무주, 남원, 진안, 장수지역의 무우, 배추 재배포장에 대한 병해발생, 기상관계, 매개진딧물 밀도등을 조사하였다. 7월부터 9월까지 순별로 조사한 결과는 다음과 같다. 발병상황은 지역적 특이성이 없고 비슷하였다. 배추의 주요병해는 흰빛썩음병, 흰무늬병, 노균병, virus병 검은무늬병 Fusarium에 의한 입고현상등이고, 무우에서는 바이러스명병, 흰녹가루병, 검은빛썩음병, 흰빛썩음병 검은 무늬병, Fusarium에 의한 입고현상등의 피해가 나타나고 있다. 발병상황을 시기적으로 보면 8월 20일경이 최고발병기이였다. 무는 총감염율이 $27\%$ 이고, 그후 점차 감소하였으나, 배추는 $20\%$의 감염상태가 계속 지속된다. 장기별 발병상황은 무우는 비대기 $25\%$, 수확기 $26\%$로 후반기에 급증한다. 배추는 초기생장기부터 계속적인 발병증가를 나타내여 결구기수확기 $20\%$의 총감염율을 나타낸다. 외국에서 보고된 Fusarium이 의한 입고현상과 Aphanomyces에 의한 근부병이 조사지역에 발병되고 있었다. 기상환경은 채소생장기간의 평균최고온도가 $25^{\circ}C$ 정도이나 우기가 겹치고, 냉량다습하여 발병의 유인적환경이였다. 매개진딧물의 분포밀도는 평난지보다 낮으며 총진딧물 대비 매개진딧물은 남원이 $73.53\%(289/393)$로 많고, 무주가 $18.12\%(31/171)$로 제일 낮았다. 매개진딧물중 우점종은 복숭아혹진딧물(Myzus persicae)이였다.

• Mycobiology
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• 제46권3호
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• pp.283-286
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• 2018

Fusarium graminearum causes the devastating plant disease Fusarium head blight and produces mycotoxins on small cultivated grains. To investigate the timeframe of F. graminearum infection during rice cultivation, a spore suspension of F. graminearum was applied to the rice cultivars Dongjin 1 and Nampyeongbyeo before and after the heading stage. The disease incidence rate was the highest (50%) directly after heading, when the greatest number of flowers were present, while only 10% of the rice infected 30 days after heading showed symptoms. To understand the mechanism of infection, an F. graminearum strain expressing green fluorescent protein (GFP) was inoculated, and the resulting infections were visually examined. Spores were found in all areas between the glume and inner seed, with the largest amount of GFP detected in the aleurone layer. When the inner part of the rice seed was infected, the pathogen was mainly observed in the embryo. These results suggest that F. graminearum migrates from the anthers to the ovaries and into the seeds during the flowering stage of rice. This study will contribute to uncovering the infection process of this pathogen in rice.

• 한국식물병리학회지
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• 제3권1호
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• pp.8-12
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• 1987

경기도 농촌진흥원에서 분양받은 녹두종자와 녹두 시험포의 뿌리 및 재배토양에서 Fusarium oxysporum, F. monitiforme, F. solani, F. equiseti, F. semitectum 및 F. sporotrichioides가 검출되었다. 종자를 대형 Petridish에서 발아시킨 유묘검정에서는 $7\%$, 자엽 및 배에서도 $2\%$의 감염율을 나타냈다. 녹두 종자에서 분리한 F. moniliforme, F. semitectum, F. equiseti 및 F. sporotrichioides를 Water-agar에서 병원성을 검정한 결과 모든 균주에서 병원성이 인정되었다. 이병근에서 F. oxysporum과 F. solani가 분리되었고, 이들의 병원성을 검정한 결과 Water-agar에서는 병원성이 인정되었으나 병원균접종토양에서는 약하게 나타났다. 재배토양에서는 F. oxysporum, F. solani 및 F. equiseti가 분리되었는데 이들도 Water-agar에서 병원성이 인정되었다. 병원균접종토양에서는 F. oxysporum과 F. equiseti는 병원성이 인정되었으나 F. solani는 병원성이 약하게 나타났다.

• The Plant Pathology Journal
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• 제37권4호
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• pp.315-328
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• 2021

Fusarium and Rhizoctonia genera are important pathogens of many field crops worldwide. They are constantly evolving and expanding their host range. Selecting resistant cultivars is an effective strategy to break their infection cycles. To this end, we screened a collection of Medicago truncatula accessions against Fusarium oxysporum, Fusarium solani, and Rhizoctonia solani strains isolated from different plant species. Despite the small collection, a biodiversity in the disease response of M. truncatula accessions ranging from resistant phenotypes to highly susceptible ones was observed. A17 showed relative resistance to all fungal strains with the lowest disease incidence and ratings while TN1.11 was among the susceptible accessions. As an initiation of the characterization of resistance mechanisms, the antioxidant enzymes' activities, at the early stages of infections, were compared between these contrasting accessions. Our results showed an increment of the antioxidant activities within A17 plants in leaves and roots. We also analyzed the responses of a population of recombinant inbred lines derived from the crossing of A17 and TN1.11 to the infection with the same fungal strains. The broad-sense heritability of measured traits ranged from 0.87 to 0.95, from 0.72 to 0.96, and from 0.14 to 0.85 under control, F. oxysporum, and R. solani conditions, respectively. This high estimated heritability underlines the importance of further molecular analysis of the observed resistance to identify selection markers that could be incorporated into a breeding program and thus improving soil-borne pathogens resistance in crops.

• 한국식품위생안전성학회지
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• 제8권2호
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• pp.23-32
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• 1993

Species of the genus Fusarium are worldwide in their distribution. They are saprophytes as soil inhabitants and parasites of cultivated plants. Some isolates of certain species car capable of producing mycotoxins. Mycotoxicoses, including moldy corn toxicosis, alimentary toxic aleukia, fusariotoxicosis, and rel mold disease are known to be associated with trichothecene-producing fungi. Historically severe epidemic of cereal scab occred in the southern part of Korea in 1963. The epidemic caused a social problem because of not only heavy economic losses but also mycotoxicoses to humans and farm animals. However the toxic principles were remained unknown until some publications in 1980's indicated that trichothecenes and zearalenone were major mycotoxins in Korea cereals contaminated with Fusarium moniliforme have been found to be associated with human and animal disease such as leukoencephalomalacia in horses, pulmonary edema in swine and esophageal cancer in humans. High concentrations of fumonisins have been detected in corn samples from high espohoageal cancer risk areas of South Africa and China. Thus fumonisins have been implicated in the etiolgy of human esophageal cancer in those high incidence countries. Recently increase of imported cereals from foreign countries demands to assess the safety of mycotoxins in Korea. The informations on the natural occurrence of mycotoxins are needed to solve the toxicological problems in humans and farm animals associated with the consumption of moldy cereals.

• 식물병연구
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• 제23권3호
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• pp.268-277
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• 2017

붉은곰팡이병은 주로 Fusarium graminearum에 의해 발생하며 전세계적으로 주요 곡물에 치명적인 피해를 주는 식물병이다. 관행농가에서는 일반적으로 붉은곰팡이병 방제에 합성살균제를 사용하고 있지만 장기적인 합성살균제의 사용으로 인하여 환경 오염 문제와 인간의 건강을 위협하는 문제가 야기되었다. 때문에 천연물살균제를 포함한 친환경 생물농약 개발에 대한 관심이 고조되고 있는 실정이다. 본 연구에서는 100종의 식물추출물을 이용하여 F. graminearum에 항진균 활성을 갖는 식물 추출물을 탐색하였다. 그 결과 자단 심재부인 자단향의 조추출물이 가장 강한 항진균활성을 보였으며, GC-MS 분석을 통하여 자단향으로부터 ${\alpha}$-cedrol과 widdrol로 동정된 두개의 항진균 활성물질을 분리하였다. ${\alpha}$-Cedrol과 widdrol의 F. graminearum 포자발아 억제활성 최소저해농도는 각각 31.25 mg/l과 62.5 mg/l였으며, 이 두 물질은 F. graminearum 이외에도 다양한 식물병원균의 균사 생육을 저해하였다. 더욱이 자단향 추출물을 분말 수화제로 제형화하여 처리한 결과, 밀 붉은 곰팡이병에 대한 방제효과는 유효성분 농도가 높을수록 효과적인 방제가를 보였으며, 250배 희석처리 시 2,000배의 상용농도로 희석한 합성살균제의 방제가(92.6%)와 통계적으로 유사한 87.2%의 병방제가를 보였다. 본 연구결과는 붉은곰팡이병방제를 위한 효과적인 생물살균제로 자단향 추출물이 활용 가능하다는 것을 제시하고 있다.

• 식물병연구
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• 제24권1호
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• pp.26-32
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• 2018

Fusarium oxysporum f. sp. fragariae (Fof)에 의한 딸기 시들음병은 국내에서 중요한 병해이다. 특히 딸기재배에서 시들음병 발생은 수경재배 면적이 증가하면서 증가하는 경향을 보이고 있다. 따라서 이 연구에서는 딸기 수경재배에서 시들음병 발생에 배양액의 pH와 EC의 영향을 in vitro와 재배포장에서 조사하였다. pH는 5, 5.5, 6, 6.5, 7, 7.5로 in vitro와 재배포장에서 검정하였고 EC는 0, 0.5, 0.8, 1, $1.5dS{\cdot}m^{-1}$로 재배포장에서 조사하였다. In vitro 상에서 딸기 시들음병균의 균사생육은 pH가 증가하면서 증가하였고 $25^{\circ}C$, pH 7에서 최대였으며 $20^{\circ}C$, pH 5에서 가장 낮았다. 재배포장에서 딸기 시들음병 발생은 pH 6.5에서 가장 낮았고 pH 5에서 가장 높은 경향을 보였다. 배양액의 pH는 높아질수록 배액의 EC는 감소하였고 딸기 잎의 칼륨함량은 증가되었다. EC 검정에서 배양액 EC가 상승함에 따라 딸기 시들음병 발생과 잎의 질소함량은 증가하였다. 이런 결과로 딸기 시들음병 발생은 수경재배에서 pH와 EC가 관련이 있다는 것을 알 수 있었다.

• 한국유기농업학회지
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• 제6권2호
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• pp.117-125
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• 1998

For isolation of antagonistic fungi antagonistic to Phytophthora capsici, a total of 157 isolates of fungi were screened from soil. Among the 157 isolates further screened by the dual culture test on potato dextrose agar and V-8 juice agar, 16 isolates were tested to show their antagonistic activity against P. capsici and Fusarium oxysporum. Fungal cul-ture filtrates of screened 16 isolates were shown to inhibit germination of zoospoorangia of P. capsici entirely and conidia of F. oxysporum considerably. Antagonistic fungi were shown to suppress of P. capsici infection of red-pepper plants maintained in the green house. Four isolates. 27 J5, 37 J10, 36 J13 and 31 K10, with the reduced disease incidence 53.3∼60.0% were identified as Fusarium sp. (27 J5). Trichoderma sp. (37 J10, 36 J13) and Penicillium sp. (31 K10).

• Animal cells and systems
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• 제9권2호
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• pp.75-78
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• 2005

Fungicides and antagonists were tested for their efficacy in the management of fungal pathogens of watermelon. The fungal species in different genera were isolated from the seeds of watermelon and their vulnerability was assessed against an array of chemicals and bioagents. Among the fungal pathogens, Fusarium species were effectively controlled by Bavistin. Topsin also showed the promising effects against all the fungal pathogens, and Dithane M-45 effectively controlled Didymella bryoniae. Seed treatment with antagonists like Trichoderma harzianum and T. viride improved the seed germination, seedling vigour and reduced the incidence of seed-borne fungal pathogens. Bavistin and Topsin among chemicals increased significantly the seed germination and vigour index. Trichoderma harzianum showed its efficacy against all Fusarium species and even stood effective than Captan and Blitox. However, Pseudomonas fIuorescens also showed promising effect against Didymella bryoniae over fungicides. Under field condition, Topsin and Dithane M-45 showed better yield than Bioagents.

• Journal of Microbiology and Biotechnology
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• 제7권1호
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• pp.13-20
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• 1997

Plant growth-promoting Psudomonas fluorescens GL20 was isolated from a ginseng rhizosphere on chrome azurol Sagar. P. fluorescens GL20 produced a large amount of hydoxamate siderophore in an iron-deficient medium. The siderophore showed significantly high specific activity of 20.2 unit. Using an in vitro antifungal test, P. fluorescens GL20 considerably suppressed growth of phytopathogenic fungus Fusarium solani, inhibiting spore germination and germ tube elongation. In pot trials of kidney beans with P. fluorescens GL20, disease incidence was remarkably reduced up to $68{\%}$ compared with that of F. solani alone, and plant growth was also increased nearly 1.6 fold as compared to that of the untreated control, promoting elongation and development of the roots. These results indicate that the plant growth-promoting activity of P. fluorescens GL20 can play an important role in biological control of soil-borne plant disease in a rhizosphere, enhancing the growth of plants.