• 생명과학회지
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• 제30권2호
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• pp.178-185
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• 2020

벼키다리병은 Fusarium fujikuroi의 감염에 의해 발생하는 대표적인 종자전염성 병이다. 이 병의 방제는 화학약제를 이용한 종자소독이 가장 효율적이지만 최근 약제에 저항성을 갖는 균주의 출현이 증가하고 있다. 미산성 차아염소산수는 환경이나 사람의 건강에는 유해성이 낮지만 바이러스, 박테리아, 곰팡이에 강력하고 광범위한 항균활성을 갖는 살균소독제로 알려져 있다. 본 연구는 화학 약제 저항성 또는 민감성 균주를 포함하는 16개의 F. fujikuroi 균주를 대상으로 미산성 차아염소산수의 항균활성을 조사하고, 이를 이용한 친환경적 병 방제 기술 개발을 목적으로 하였다. 미산성 차아염소산수는 화학약제 저항성 균주를 포함한 조사한 F. fujikuroi 균주 모두에 대해 유리염소 5±2.5 ppm 농도에서 비특이적이고 강한 항균 활성을 나타냈고, 처리 후 5분 이내에 F. fujikuroi 세포의 치명적 손상과 함께 완전한 살균 효과를 나타났다. F. fujikuroi 균주로 감염된 벼 종자를 20±10 ppm의 유리염소를 포함하는 미산성 차아염소산수로 12시간 침지 소독하였을 경우, 종자 소독 효과와 병 방제율은 각각 95~98%와 90.1~92.6%였다.

• Mycobiology
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• 제30권3호
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• pp.139-145
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• 2002

Gibberella fujikuroi is species complex. This species complex includes Fusarium tabacinum, F. moniliforme(=F. verticillioides), F. nygamai, F. proliferatum as well as F. subglutinans. Our objective was to develop a technique to differentiate between isolates of F. subglutinans, F. proliferatum and F. verticillioides. Thirty-two strains of F. subglutinans, six strains from F. verticillioides and five strains of F. Proliferatum isolated from maize in Austria were studied using random amplified polymorphic DNA(RAPD). F. subglutinans strains clustered very closely, with similarity ranging from $87{\sim}100%$. On the other hand, all the amplification patterns of F. verticillioides were identical, as well as in the case of F. proliferatum. Our results indicated that these Fusaria species are distinct species and hence RAPD markers can be quick and reliable for differentiating them.

• 농약과학회지
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• 제12권3호
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• pp.277-282
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• 2008

Fusarium spp. 균주들에 대한 Prochloraz의 살균효과를 비교하기 위하여 한천희석법을 사용하여 각 균주에 대한 prochloraz의 $EC_{50}$값을 구하였다. 전체 균주에 대한 평균 $EC_{50}$값은 $0.25{\mu}g\;mL^{-1}$이었으며, 최저값과 최고값은 0.02과 $1.78{\mu}g\;mL^{-1}$이었다. Fusarium의 종별로 조사한 평균 $EC_{50}$값을 보면 F. fujikuroi의 경우가 $0.31{\mu}g\;mL^{-1}$, F. moniliformis와 F. proliferatum의 경우는 0.09과 $0.11{\mu}g\;mL^{-1}$이었다. 실험에 사용한 36개 Fusarium 속 균주의 Prochloraz에 대한 감수성과 저항성을 판단할 수 있는 기준 $EC_{50}$ 값은 $0.5{\mu}g\;mL^{-1}$가 타당하며, 이 기준에 의한 저항성 균주의 분리 비율은 13.8%이었다. Prochloraz에 대한 저항성과 Fusarium 균주의 병원성간에는 전혀 상관관계가 없었다. 또한 prochloraz에 대해서 저항성인 균주들은 triflumizole, hexaconazole, difenoconazole, tebuconazole과 교차 저항성을 보이지 않았다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.25-25
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• 2014

Three species of Fusarium, F. fujikuroi, F. verticillioides and F. proliferatum, are known to be associated with bakanae disease of rice [1, 2]. F. fujikuroi infects rice flowers and survive in endosperm and embryo of the seeds. Infected seed is an important source of primary inoculum of pathogens [3]. Seeds of rice (Oryza sativa cv. Boramchan) collected from bakanae-infected field were found to be 96% infected with Fusarium sp., 52% with F. fujikuroi, 42% with F. verticillioides, and 12% with F. proliferatum as determined by incubation method and species-specific PCR assays. F. fujikuroi was detected at lemma/palea, endosperm and embryo whereas F. verticillioides and F. proliferatum were recovered only from lemma/palea by means of component plating test. Seed disinfection methods have been developed to control bakanae disease and prochloraz has been most widely used for rice seeds. Two chemicals formulated with prochloraz (PC 1) and prochloraz + hexaconazole (PC 2) that inhibit biosynthesis of ergosterol strongly reduced the incidence of Fusarium spp. on selective media to 4.7% and 2.0%, respectively. Disease symptoms of rice seedlings in nursery soil were alleviated by chemical treatment; seedlings with elongated leaves or wide angle between leaf and stem were strikingly reduced from 15.6 to 3.2% (PC 1) and 0 (PC 2), stem rots were reduced from 56.9 to 26.2% (PC 1) and 32.1% (PC 2), and normal seedling increased from 0.4 to 13.3% (PC 2). Prochloraz has some disadvantages and risks such as the occurrence of tolerant pathogens [4] and effects on the sterol synthesis in animals and humans [5]. For these reasons, it is necessary to develop new disinfection method that do not induce fungal tolerance and are safe to humans and animals. Chlorine dioxide ($ClO_2$), that is less toxic, produces no harmful byproducts, and has high oxidizing power, has been reported to be effective at disinfection of several phytopathogenic fungi including Colletotrichum spp. and Alternaria spp. [6]. Gaseous $ClO_2$ applied to rice seeds at a concentration of 20 ppm strongly suppressed mycelial growth of Fusarium fujikuroi, F. verticillioides and F. proliferatum. The incidence of Fusarium spp. in dry seed with 8.7% seed moisture content (SMC) tended to decrease as the concentration of $ClO_2$ increased from 20 to 40 ppm. Applying 40 ppm $ClO_2$ at 90% relative humidity, incidence was reduced to 5.3% and resulted in significant reduction of disease symptoms on MS media. In nursery soil, stem rot was reduced from 56.9 to 15.4% and the number of normal seedlings increased from 0.4 to 25.5%. With water-soaked seeds (33.1% SMC) holding moisture in the endosperm and embryo, the effectiveness of disinfection using $ClO_2$ increased, even when treated with only 20 ppm for four hours. This suggests that moisture was a key element for action of $ClO_2$. Removal of the palea and lemma from seeds significantly decreased the incidence of Fusarium spp. to 3.0%. Seed germination appeared to decrease slightly by water-soaking at $30^{\circ}C$ because of increased SMC and by physical damage of embryos from hulling. These results indicate that the use of gaseous $ClO_2$ was effective as a means to disinfect rice seeds infected with Fusarium spp. and that moisture around the pathogens in the seed was an important factor for the action of $ClO_2$. Further investigations should be conducted to ascertain the best conditions for complete disinfection of Fusarium spp. that infect deep site of rice seeds.

• 생명과학회지
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• 제34권4호
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• pp.215-226
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• 2024

독활 뿌리 추출물은 한국을 포함한 극동아시아 국가에 널리 분포하고 있다. 이 추출물은 한국에서 두통, 염증, 허리통증 및 치과질환 등 다양한 질환에 오랫동안 사용되어져 왔다. 활성물질은 에피-콘티넨탈산, 콘티넨탈산 그리고 카우레노산으로 동정되었다. 생체이용능을 향상시킨 디테르페노이드 유도체의 합성을 위해, Fusarium fujikuroi가 생물전환용 균주로 선발되었다. 생물전환을 통하여 16α-hydroxy-ent-kauran-2-on-19-oic acid 와 2β, 16α-dihydroxy-ent-kauran-19-oic acid의 두 가지 유도체가 얻어졌으며, 이들의 화학구조는 HPLC, MS 및 NMR 분석을 통해 확인되었다. 이러한 유도체들은 HPLC에서의 산물 유출시간과 구조적 특성을 통해 카우레노산에 비해 증가된 극성을 나타내었다. 인슐린 신호전달경로의 음성조절자인 PTP1B를 대상으로 한 항당뇨 활성을 평가한 결과, 4 ㎍/ml 농도에서 각각 30.8% 및 27.6%의 억제율을 나타냈으며, 두 유도체는 기존의 카우레노산 보다 18배 높은 IC₅₀ 값을 갖는 낮은 세포독성을 보여주었다. 따라서, F. fujikuroi에 의한 생물전환으로 인해 증가된 수용성과 감소된 독성을 갖는 두 카우레노산 유도체는 산업적 응용을 위한 유망한 후보물질로 평가된다.

• 식물병연구
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• 제17권3호
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• pp.369-375
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• 2011

Fusarium verticillioides(완전세대: Gibberella moniliformis)는 Gibberellea fujikuroi 종 복합체에 속하는 식물병원균으로서 옥수수의 줄기와 이삭에 썩음병을 일으킬 뿐 아니라 인축에 중독증을 일으키는 fumonisin 곰팡이 독소를 생산한다. 본 연구의 목적은 옥수수에 주로 발생하는 fumonisin 생성가능 G. fujikuori 종 복합체 소속 Fusarium 곰팡이 중 F. verticillioides와 그 외 F. proliferatum, F. fujikuori 등을 서로 구별할 수 있는 종 특이적 PCR primer 조합을 개발하는 것이다. RNA polymerase II beta subunit 유전자(RPB2)의 염기서열로부터 제작된 특이 primer 조합(RVERT1와 RVERT2)은 우리나라 옥수수에서 분리한 잠재적인 fumonisin 생성 G. fujikuori 종 복합체 균주 중 오직 F. verticillioides로부터 208 bp 크기의 단일 DNA 절편을 증폭하였다. 한편 F. verticillioides를 포함한 모든 조사균주는 fumonisin 생합성에 필수적인 FUM1 유전자를 포함하고 있었다. 개발된 특이 primer 조합의 검출한계는 분석 곰팡이 DNA 0.125 pg/${\mu}l$ 수준이었다. 한편, 같은 primer 조합으로 Fusarium spp.에 오염된 옥수수 시료의 게놈 DNA로부터 F. verticillioides 특이 DNA 절편이 증폭되었다. 이와 같은 결과를 종합할 때, 본 연구에서 개발된 primer 조합은 여러 곡물 시료에 오염되어 있는 F. verticillioides 균주의 검출과 종 동정에 유용하게 사용될 것이다.

• Mycobiology
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• 제41권4호
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• pp.225-233
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• 2013

Gibberella fujikuroi species complex (GFSC) was isolated from rice (Oryza sativa L.) seed samples from ten Asian countries and investigated for incidence of GFSC, molecular characteristics, and pathogenicity. Regardless of geographic origin, GFSC was detected with incidences ranging from 3% to 80%. Four species, Fusarium fujikuroi, F. concentricum, F. proliferatum, and F. verticillioides, were found to show an association with rice seeds, with F. fujikuroi being the predominant species. In phylogenetic analyses of DNA sequences, no relationship was found between species, isolates, and geographic sources of samples. Unidentified fragments of the ${\beta}$-tubulin gene were observed in ten isolates of F. fujikuroi and F. verticillioides. With the exception of three isolates of F. fujikuroi, F. fujikuroi, F. proliferatum, and F. verticillioides were found to have FUM1 (the fumonisin biosynthetic gene); however, FUM1 was not found in isolates of F. concentricum. Results of pathogenicity testing showed that all isolates caused reduced germination of rice seed. In addition, F. fujikuroi and F. concentricum caused typical symptoms of bakanae, leaf elongation and chlorosis, whereas F. proliferatum and F. verticillioides only caused stunting of seedlings. These findings provide insight into the characteristics of GFSC associated with rice seeds and might be helpful in development of strategies for management of bakanae.

• 한국환경농학회지
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• 제31권1호
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• pp.30-36
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• 2012

BACKGROUND: The resistance of rice bakanae disease pathogens against the fungicide prochloraz has been reported. Understanding the resistance mechanisms is an important for better control of the pathogens. In the present study, we investigated the resistance mechanisms of Fusarium fujikuroi CF337 (CF337) against prochloraz. METHODS AND RESULTS: Morphological changes in the cell wall of CF337 grown in potato dextrose broth (PDB) with or without prochloraz was investigated by transmission electron microscopy. Growth inhibition of CF337 was examined in PDB containing prochloraz or an ABC transporter inhibitor or both of them. Cell wall thickness of CF337 grown in PDB with prochloraz was significantly increased from $80.73{\pm}1.99nm$ to $193.11{\pm}7.07nm$. Significant inhibition in the growth of CF337 was observed in the presence of both prochloraz and the inhibitor, but no growth inhibition was observed in the presence of the inhibitor or prochloraz. Sequence analysis of ATP-binding cassette transporter (ABC) gene of CF337 showed 70 to 80% similarities to the genes of the pathogens resistant to other fungicides. CONCLUSION: Efflux transporter system and changes in cell wall thickness were suggested as resistance mechanisms of CF337 against prochloraz.

• Mycobiology
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• 제51권4호
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• pp.195-209
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• 2023

The seed borne disease such as bakanae is difficult to control. Crop yield loss caused by bakanae depending on the regions and varieties grown, ranging from 3.0% to 95.4%. Bakanae is an important disease of rice worldwide and the pathogen was identified as Fusarium fujikuroi Nirenberg (teleomorph: Gibberella fujikuroi Sawada). Currently, four Fusaria (F. fujikuroi, F. proliferatum, F. verticillioides and F. andiyazi) belonging to F. fujikuroi species complex are generally known as the pathogens of bakanae. The infection occurs through both seed and soil-borne transmission. When infection occurs during the heading stage, rice seeds become contaminated. Molecular detection of pathogens of bakanae is important because identification based on morphological and biological characters could lead to incorrect species designation and time-consuming. Seed disinfection has been studied for a long time in Korea for the management of the bakanae disease of rice. As seed disinfectants have been studied to control bakanae, resistance studies to chemicals have been also conducted. Presently biological control and resistant varieties are not widely used. The detection of this pathogen is critical for seed certification and for preventing field infections. In South Korea, bakanae is designated as a regulated pathogen. To provide highly qualified rice seeds to farms, Korea Seed & Variety Service (KSVS) has been producing and distributing certified rice seeds for producing healthy rice in fields. Therefore, the objective of the study is to summarize the recent progress in molecular identification, fungicide resistance, and the management strategy of bakanae.

• 한국유기농업학회지
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• 제24권1호
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• pp.61-71
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• 2016

본 연구에서는 흑타리버섯을 물, 에틸아세테이트, 클로로포름, 부탄올 등으로 추출하였다. 각 유기용매를 이용한 흑타리버섯 추출물의 항균 활성을 1차적으로 평판 확산방법을 사용하여 항균력을 검증하였다. 부탄올 추출물에서 가장 높은 항균력을 확인하였고, 1%, 2.5%, 5%, 7.5%, 10% 농도로 항균력을 확인하였을 때도 부탄올 추출물이 가장 높은 항균활성을 확인하였다. 위의 결과를 통해 실제 포장실험에서도 가능성을 확인하여 온실에서 F. fujikuroi Nirenberg의 억제력을 확인해본 결과 흑타리버섯 부탄올 추출물을 7.5% 첨가하였을 때 .80%의 높은 억제력을 확인할 수 있었다. 또한 초기의 발아력과 파종 후 30일 경과 후에 확인한 초기 생육특성에서도 흑타리버섯 추출물의 5% 이상에서는 방제에 효과가 높았으며 7.5% 이상 시에는 초장 및 묘소질이 대조구와 비교하여 통계적 유의차가 없는 높은 방제효과를 확인할 수 있었고 이러한 결과로 볼 때 흑타리버섯 추출물은 벼 키다리병에 대하여 높은 방제효과가 있으며 향후에는 친환경 종자소독제로써 활용가능성이 높을 것으로 판단된다.