• Journal of Microbiology and Biotechnology
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• 제26권6호
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• pp.1103-1108
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• 2016

Yam anthracnose caused by Colletotrichum gloeosporioides (C.g) is the most devastating disease of yam (Dioscorea sp.). In the present study, we evaluated the culture filtrate extract (CFE) of azalomycin-producing Streptomyces malaysiensis strain MJM1968 for the control of yam anthracnose. MJM1968 showed strong antagonistic activity against C.g in vitro. Furthermore, the MJM1968 CFE was tested for inhibition of spore germination in C.g, where it completely inhibited spore germination at a concentration of 50 μg/ml. To assess the in planta efficacy of the CFE and spores of MJM1968 against C.g, a detached leaf bioassay was conducted, which showed both the treatments suppressed anthracnose development on detached yam leaves. Furthermore, a greenhouse study was conducted to evaluate the CFE from MJM1968 as a fungicide for the control of yam anthracnose. The CFE non-treated plants showed a disease severity of >92% after 90 days of artificial inoculation with C.g, whereas the disease severity of CFE-treated and benomyl-treated yam plants was reduced to 26% and 15%, respectively, after 90 days. Analysis of the yam tubers from the CFE-treated and non-treated groups showed that tubers from the CFE-treated plants were larger than that of non-treated plants, which produced abnormal smaller tubers typical of anthracnose. This study demonstrated the utility of the CFE from S. malaysiensis strain MJM1968 as a biofungicide for the control of yam anthracnose.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.30-31
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• 2003

Total 291 isolates of Ampelomyces quisqualis were obtained from 32 species of powdery mildew fungi and a selected isolate, Ampelomyces quisqualis 94013 (AQ94013) effectively hyperparasitized 6 species of Sphaerotheca and one species of Erysiphe which cause serious damage on many important crops in Korea. Moreover, AQ94013 showed antagonistic effects against 12 major fungal plant pathogens as well. Results indicated that the present isolate is not a host specific hyperparasite and has a broad spectrum of biocontrol potential. Providentially, AQ94013 revealed resistance to a number of agrochemicals so as to be applied with the chemicals reciprocally.(중략)

• 식물병연구
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• 제21권3호
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• pp.208-214
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• 2015

고추 재배토양에서 분리한 세균 중에서 고추탄저병균의 균사생장을 강하게 억제하며 분생포자의 발아를 현저히 억제하는 균주를 선발하였다. 이 균의 형태적 생리적 실험과 16S rRNA 분석결과를 토대로 Bacillus sp KBC1004로 명명하였다. KBC1004를 동결 건조하여 얻은 건조물을 원제로 하여 탄수화물과 증량제를 포함하는 수화제형($2{\times}10^8cfu/g$)으로 제조하였을 때 상온에서 2년 이상 안정된 밀도를 유지하였다. 수화제 형태의 KBC1004가 활성화 되어 탄저병균 분생포자의 발아를 억제하려면 최소 24시간이 경과되어야 하였고 실내에서 고추 열매를 이용하여 탄저병의 발병 억제력을 조사한 결과도 24시간 전에 KBC1004 수화제를 살포하고 병원균을 접종하였을 때 효과적인 병 방제가 이루어졌다. 고추포장에서 KBC1004 수화제를 500배로 희석하여 탄저병이 발생하는 6월 말부터 4회 처리하고 10일 경과 후 이병과율을 조사한 결과 화학농약의 방제가가 86.3%이였을 때 80.3%의 높은 방제가를 나타내었다.

• The Plant Pathology Journal
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• 제22권4호
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• pp.381-385
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• 2006

Antifungal activity of Korean and Chinese lichen-forming fungi(LFF) was evaluated against plant pathogenic fungi of Botryosphaeria dothidea, Botrytis cinerea, Diaporthe actinidiae, Pestalotiopsis longiseta, Pythium sp., Rhizoctonia solani, and Sclerotium cepivorum. The LFF were isolated from Cladonia scabriuscula, Melanelia sp., Nephromopsis asahinae, Nephromopsis pallescens, Parmelia laevior, Pertusaria sp., Ramalina conduplicans, Ramalina sinensis, Ramalina sp., Umbilicaria proboscidea and Vulpicida sp. with discharged spore method. The isolates were deposited in the herbarium of Korean Lichen Research Institute(KoLRI) in Sunchon National University. The LFF of Melanelia sp., P. laevior, Pertusaria sp., R. conduplican and Ramalina sp. exhibited strong antifungal activity against all of the pathogenic fungi examined. Among them, LFF of P. laevior showed more than 90% of inhibition in fungal hyphae growth, compared with control. The results imply that LFF can be served as a promising bioresource to develop novel biofungicides. Mass cultivation of the LFF is now under progress in laboratory conditions for chemical identification of antifungal substances.

• The Plant Pathology Journal
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• 제24권2호
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• pp.202-206
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• 2008

Antifungal activity of Korean and Chinese lichen-forming fungi (LFF) was evaluated against plant pathogenic fungus of Colletotrichum acutatum, causal agent of anthracnose on hot pepper. This is the first attempt to evaluate antifungal activity of LFF, instead of lichen thalli, against C. acutatum. Total 100 LFF were isolated from the lichens with discharged spore method or tissue culture method. Among the 100 isolates, 8 LFF showed more than 50% of inhibition rates of mycelial growth of the target pathogen. Especially, Lecanora argentata was highly effective in inhibition of mycelial growth of C. accutatum at the rate of 68%. Antifungal activity of other LFF was in the order of Cetrelia japonica (61.4%), Ramalina conduplicans (59.5%), Umbilicaria esculenta (59.5%), Ramalina litoralis (56.7%), Cetrelia braunsiana (56.5%), Nephromopsis pallescensn (56.1%), and Parmelia simplicior (53.8%). Among the tested LFF, 61 isolates of LFF exhibited moderate antifungal activity against the target pathogen at the inhibition rates from 30 to 50%. Antifungal activity of the LFF against C. acutatum was variable at the species level rather than genus level of LFF. This study suggests that LFF can be served as a promising bioresource to develop novel biofungicides.

• The Plant Pathology Journal
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• 제25권1호
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• pp.38-46
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• 2009

Lichen-forming fungi (LEF) were isolated from 67 Hungarian lichen species from ascospores or thallus fragments. LFF were successfully isolated from 26 species with isolation rate of 38.8%. Of the total number of isolation from ascospores (27 species) and thallus fragments (40 species), 48% and 32.5% of the species were successfully isolated, respectively. Comparison of rDNA sequences of ITS regions between the isolated LFF and the original thallus confirmed that all the isolates originated from the thallus fragments were LEF. The following 14 species of LEF were newly isolated in this study; Acarospora cervina, Bacidia rubella, Cladonia pyxidata, Lasallia pustulata, Lecania hyaline, Lecanora argentata, Parmelina tiliacea, Parmotrema chinense, Physconia distorta, Protoparmeliopsis muralis, Ramalina pollinaria, Sarcogyne regularis, Umbilicaria hirsuta, Xanthoparmelia conspersa and X. stenophylla. Antifungal activity of the Hungarian LFF was evaluated against plant pathogenic fungi of Colletotrichum acutatum, C. coccodes and C. gloeosporioides, causal agent of anthracnose on hot pepper. Among the 26 isolates, 11 LFF showed more than 50% of inhibition rates of mycelial growth of at least one target pathogen. Especially, LFF of Evernia prunastri, Lecania hyalina and Lecanora argentata were remarkably effective in inhibition of mycelial growth of all the tested pathogens with antibiotic mode of action. On the other hands, five isolates of Cladonia furcata, Hypogymnia physodes, Lasallia pustulata, Ramalina fastigiata and Ramalina pollinaria exhibited fungal lytic activity against all the three pathogens. Among the tested fungal pathogens, C. coccodes seemed to be most sensitive to the LFF. The Hungarian LFF firstly isolated in this study can be served as novel bioresources to develop new biofungicides alternative to current fungicides to control hot pepper anthracnose pathogenic fungi.

• 식물병연구
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• 제13권3호
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• pp.197-203
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• 2007

Ampelomyces quisqualis 94013(AQ94013)이 오이 흰가루병의 생물적 방제를 위하여 효과적인 기생균으로 선발되었다. 온실에서 AQ94013의 포자현탁액을 $5.0{\times}10^6/ml$ 또는 $5.0{\times}10^7/ml$를 예방적으로 경엽 살포하여 9일간 오이 흰가루병의 발생을 상당히 억제시켰다. 오이 흰가루병이 발생한 후에 AQ94013의 포자현탁액$(5.0{times}10^6/ml)$을 처리하였을 때에도 3일에서 7일내에 흰가루병을 효과적으로 억제시켰다. 오이재배 비닐하우스에서 AQ94013의 포자현탁액$(5{\times}10^6/ml)$을 7일 간격 3회 처리는 AQ94013의 포자현탁액의 10일 간격 2회 처리와 화학약제 훼나리몰유제를 2회 처리한 것 보다 오이 흰가루병 방제 효과가 높았다. 그러므로 AQ94013균주는 오이 흰가루병 생물적 방제을 위하여 유망한 미생물살균제로 개발할 필요가 있다고 판단되었다.

• The Plant Pathology Journal
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• 제24권3호
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• pp.322-327
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• 2008

Antifungal activities of natural substrances from Eucalyptus darlympleana, E. globules, E. gunnii and E. unigera were evaluated against postharvest pathogens of kiwifruits, Botrytis cinerea, Botryosphaeria dothidea, and Diaporthe actinidiae, to screen effective natural substances as an alternative to chemical fungicides. Methanol extract of the Eucalyptus trees showed strong antagonistic activity against the pathogenic fungi. Among them, E. unigera and E. darlympleana effectively inhibited mycelial growth of the pathogens. For chemical identification of the antifungal substances, the methanol extract of E. darlympleana leaves was successively partitioned with $CH_2Cl_2$, EtOAc, n-BuOH and $H_2O$. Among the fractions, $CH_2Cl_2$ and n-BuOH showed strong inhibitory activity of mycelial growth of the fungi. Five compounds were isolated from EtOAc and n-BuOH fractions subjected to $SiO_2$ column chromatography. Two phenolic compounds(gallic acid and 3,4-dihydroxybenzoic acid) and three flavonoid compounds(quercetin, quercetin-3-O-$\alpha$-L-rhamnoside, quercetin-3-O-$\beta$-glucoside) were identified by $^1H$-NMR and $^{13}C$-NMR spectroscopy. Among them, only gallic acid was found to be effective in mycelial growth and spore germination of B. cinerea at relatively high concentrations. The results suggest that gallic acid can be a safer and more acceptable alternative to current synthetic fungicides controlling soft rot decay of kiwifruit during postharvest storage.

• 생명과학회지
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• 제11권3호
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• pp.235-241
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• 2001

To select the sntagonistic bacteria against B. cinerea, isolates were screened from the eggplant leaves and rhizosphere soils in the eggplnat fields in the greenhouse. W1 and P99 isolates were selected by the inhibition of mycelial growth of B. cinerea E12 in vitro test. These isolates, W1 and P99, were identified as Bacillus subtilis and Pseudomonas putida, respectively, by the Bergeys manual and API systems, For the formulation of the antagonistic bacteria, the media for the mass production were prepared with biji(soybean curd residues) or soybean flour. B. subtilis W1 or P. putida P99 was mass cultured in biji broth or soybean flour extrect broth and then soybean flour, corn starch flour, rice glutinous flour and biji flour as high molecular substrates were added. These mixtures were dried, grinded and formulated as brofungicides of wettable powder type. The assess the control effect of biofungicides against the infection of B. cinerea, six types of formulations were assayed at the pot culturing with eggplant in the greenhouse. According to the results, there were no significant differences among the formulation methods. However, P99S or PppB formulated with P. putida P99 showed the highest control values as 90.4% and 96.1%, respectively. Then. BSB or BSD formulated whit B. subtilis W1 were 80.8% and 83.0%, respectively. There afforementioned values were more effective than that of chemical fungicide. Ipro W.P which showed as 72.6%.

• 한국균학회지
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• 제44권3호
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• pp.176-183
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• 2016

Bacillusvelezensis CC112 균주는 인삼 잘록병을 일으키는 Rhizoctonia solani를 비롯한 여러 식물병원균의 균사 생장을 억제하였다. 인삼 잘록병균 R. solani에 대하여 B. velezensis CC112 균주를 Luria-Bertani (LB)와 Bacillus-soytone medium 배지에 배양한 10배 희석액의 종자침지처리와 LB 배지에 배양한 10배 희석액을 토양관주처리하여 65.8%, 67.1%와 64.2% 방제효과를 나타냈다. B.velezensis CC112 균주의 시제품을 100배로 희석하여 토양관주처리하여 R. solani에 77.3%, Pythium sp.에 65.7% 방제효과를 각각 나타내었다. 이들 결과에서 B. velezensis CC112 균주는 인삼 잘록병의 방제에 유망한 미생물살균제가 될 수 있다.