• The Plant Pathology Journal
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• 제20권3호
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• pp.184-191
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• 2004

Methanol extracts of fresh materials of 57 plants were screened for in vivo antifungal activity against Magna-porthe grisea, Corticium sasaki, Botrytis cinerea, Phyto-phthora infestans, Puccinia recondita, and Blumeria graminis f. sp. hordei. Among them, seven plant extracts showed disease-control efficacy of more than 90％ against at least one of six plant diseases. None of the plant extracts was highly active against tomato gray mold. The methanol extracts of Chloranthus japonicus (roots) (CjR) and Paulownia coreana (stems) (PcS) displayed the highest antifungal activity; the CjR extract controlled the development of rice blast, rice sheath blight, and wheat leaf rust more than 90％, and tomato gray mold and tomato late blight more than 80％. The PcS extract displayed control values of more than 90 ％ against rice blast, wheat leaf rust, and barley powdery mildew and more than 80％ against tomato gray mold. The extract of PcS also had a curative activity against rice sheath blight and that of CjR had a little curative activity against rice blast. On the other hand, the extract of Rumex acetocella roots reduced specifically the development of barley powdery mildew. Further studies on the characterization of antifungal substances in antifungal plant extracts are underway and their disease-control efficacy should be examined under greenhouse and field conditions.

• 한국미생물·생명공학회지
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• 제30권4호
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• pp.339-345
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• 2002

가지에서 분리한 F. equiseti FO-68균주와 벗풀에서 분리한 Fusarium sp. FO-510균주로부터 항균물질을 분리한 후 이들의 식물병원곰팡이에 대한 항균활성을 in vitro및 in vivo에서 조사하였다. FO-68균주의 쌀배양체로부터 하나의 항생물질을 순화하였는데 , 이 물질은 equisetin이라는 물질로 동정되었다. 그리고 FO-510균주의 쌀배양체로부터는 두 개의 항균활성 물질을 분리하였는데, 이들은 zearalenone과 8'-hydroxyzearalenone으로 동정되었다. Equisetin과 zearalenone은 in vitro에서 실험한 식물병원곰팡이 대부분에 대해서 높은 항균활성을 보였지만, 8'-hydroxyzearalenone은 거의 항균활성이 없었다. In vivo assay에서 equisetin은 토마토ㆍ잿빛곰팡이병과 토마토ㆍ역병에 방제효과가 컸으며, zearalenone은 벼ㆍ도열병, 벼ㆍ잎집무의마름병, 토마토ㆍ잿빛곰팡이병 및 토마토ㆍ역병에 대하여 효과를 나타내었다. 하지만 8'-hydroxyzearalenone는 토마토ㆍ잿빛곰팡이병을 제외한 나머지 식물병의 발생은 억제하지 못했다. Equisetin, zearalenone 및 8'-hydroxyzearalenone의 항진균활성은 본 논문에서 처음으로 보고하는 바이다.

• 한국약용작물학회지
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• 제22권6호
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• pp.483-488
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• 2014

Lime-bordeaux mixture (LBM) has been used instead of pesticides in ginseng field and orchard since the 1960's in Korea. In this experiment, LBM was made with different concentrations and sprayed in the field of ginseng for eco-friendly cultivation. Growth characteristics and disease such as alternaria blight, anthracnose, and gray mold were investigated in 4-5 year old ginseng after spraying LBM. LBM caused a little damage on leaf when it was sprayed at the time of leafing stage, late April and early May. Root weights of five-year-old ginseng were 43.1~51.5 g and 41.2~46.6 g in the plot of mid-April and mid-May treatments, respectively. These growth levels were further reduced as compared with that of the chemicals treatment plot. The rate of diseases in the plot of 6-6 and 8-8 ratio were 0.0~4.8% and 0.0~4.4%, respectively, which was similar with that in the plot of chemical control for alternaria blight and anthracnose. However, LBM had little effect on controling gray mold. It showed lower control effect in the plot of 4-4 ratio than that of chemical control. This result will be expected to be a useful guide that can be used in the field to the farmers of the ginseng.

• 식물병연구
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• 제17권3호
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• pp.364-368
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• 2011

Gray mold caused by Botrytis cinerea was found on a carrot seedling in a greenhouse and a field at Daegwallryeong, Gangwon Province in 2007-2009. Symptoms included irregular, brown, blight, or chlorotic halo on leaves and petioles of the carrots. Fungal conidia were globose to subglobose or ellipsoid, hyaline or pale brown, nonseptate, one celled, $7.2-18.2{\times}4.5-11\;{\mu}m$ ($12.1{\times}8.3\;{\mu}m$) in size, and were formed on botryose heads. B. cinerea colonies were hyaline on PDA, and then turned gray and later changed dark gray or brown when spores appeared. The fungal growth stopped at $35^{\circ}C$, temperature range for proper growth was $15-25^{\circ}C$ on MEA and PDA. Carrots inoculated with $1{\times}10^5$ ml conidial suspension were incubated in a moist chamber at $25{\pm}1^{\circ}C$ for pathogenicity testing. Symptoms included irregular, brown, water-soaked rot on carrot roots and irregular, pale brown or dark brown, water-soaked rot on leaves. Symptoms were similar to the original symptoms under natural conditions. The pathogen was reisolated from diseased leaves, sliced roots, and whole roots after inoculation. As a result, this is the first report of carrot gray mold caused by B. cinerea in Korea.

• The Plant Pathology Journal
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• 제25권2호
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• pp.165-171
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• 2009

Biological control activity of Acremonium strictum BCP, a mycoparasite on Botrytis cinerea, was examined against six plant diseases such as rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew in growth chambers. The spore suspension of strain BCP showed strong control activities against five plant diseases except against wheat leaf rust. On the other hand, the culture filtrate of A. strictum BCP was effective in controlling only cucumber gray mold and barley powdery mildew. Further in vivo biocontrol activities of A. strictum BCP against tomato gray mold were investigated under greenhouse conditions. Control efficacy of the fungus on tomato gray mold increased in a concentration-dependent manner. Treatment of more than $1{\times}10^6$ spores/ml significantly controlled the disease both in tomato seedlings and in adult plants. The high disease control activity was obtained from protective application of the strain BCP, whereas the curative application did not control the disease. Foliar infections of B. cinerea were controlled with $1{\times}10^8$ spores/ml of A. strictum BCP applied up to 7 days before inoculation. In a commercial greenhouse, application of A. strictum BCP exhibited the similar control efficacy with fungicide procymidone (recommended rate, $500{\mu}g/ml$) against strawberry gray mold. These results indicate that A. strictum BCP could be developed as a biofungicide for Botrytis diseases under greenhouse conditions.

• The Plant Pathology Journal
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• 제21권3호
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• pp.207-213
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• 2005

Cultural, morphological and pathogenic variation in Indian isolates of Ascochyta rabiei, the causal agent of blight of chickpea, was investigated. Fungal isolates representative of seven agroclimatic regions in north western plain zones (NWPZ) of India showed variation in colony colour as mouse gray with green hue, light mouse gray with slate gray centre and gray with dark brown centre, when grown on chickpea dextrose agar (CDA). Conidiomatal color of the isolates varied from brown to slate gray and black. The number of conidiomata and conidia formed on CDA ranged from 49.7 to 90.7 and $5.5\times10^4\;to\;3\times10^5cm^{-2}$, respectively. The size of conidiomata and conidia of A. rabiei isolates varied from $274\times232{\mu}m\;to\;156\times116{\mu}m$, and from $14.0\times6.2{\mu}m\;to\;10.7\times4.6{\mu}m$, respectively. Fourteen A. rabiei isolates from the seven agroclimatic regions of NWPZ were evaluated for their virulence on 180 chickpea genotypes in controlled environment. Cluster analysis based on the disease rating on a 1-9 scale indicated higher similarity coefficient (> 0.65) between isolates from different agroecological regions, while few isolates from the same region had less similarity. The 14 isolates were grouped into eight pathotypes at > 0.5 similarity coefficient. Sixteen genotypes were identified as probable differentials to distinguish A. rabiei isolates.

• 식물병연구
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• 제12권2호
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• pp.85-90
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• 2006

차나무 겹퉁근무늬병을 일으키는 Pestalotiopsis longiseta에 대하여 강력한 길항능력을 나타내는 Bacillus subtilis BD0310 균주의 대량배양을 위한 배양조건과 P. longiseta에 대한 항균활성을 증대시킬 수 있는 탄소원과 질소원을 선발하였다. B. subtilis BD0310 균주를 대량배양하기 위한 최적온도 및 시간은 $30^{\circ}C$, 24 시간인 것으로 확인되었으며, 초기 최적 pH 는 7 로 확인되었다. B. subtilis BD03l0 균주를 대량으로 배양할 경우 P. longiseta에 대한 항균활성을 가장 높게 증가시키는 탄소원을 선발하기 위하여 fructose, galactose, glucose, glycerol, inositol, lactose, maltose, sorbitol, starch 등 9 가지 탄소원을 사용하여 조사한 결과 maltose와 inositol이 가장 효율적인 탄소원으로 선발되었으며, casein, tryptone, malt extract, yeast extract, $(NH_4)_2SO_4$등 5 가지 질소원 중에서 yeast extract와 tryptone이 가장 효율적인 질소원으로 선발되었다. 이러 한 결과들은 길항세균 B. subtilis BD0310를 차나무 겹둥근무늬병 방제용 미생물제제로 개발하기 위한 대량배양생산 공정을 확립하는데 기여할 것으로 전망된다.

• The Plant Pathology Journal
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• 제17권5호
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• pp.305-307
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• 2001

In March 2000, gray mold was found on day lily (Hemerocallis fulva L.) in Korea. Among the symptoms observed was blight or early rot with chlorotic halo of the leaves. All the isolates obtained from the lesions of the diseased plant parts were identified as Botrytis elliptica, based on the morphological characteristics of conidia. Conidia that formed on conidiogenous cells were not in chains, hyaline to pale brown, unicellular, ellipsoidal to obovate with a single hilum at the base, entirely verruculose, and 21-31 x 12-$23\mu\textrm{m}$ in size. Pathogenicity of the fungus was established by artificial inoculation on day lily plants. This is the first record of gray mold on day lily caused by B. elliptica in Korea.

• The Plant Pathology Journal
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• 제26권2호
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• pp.170-177
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• 2010

Bacillus licheniformis N1, previously developed as a biofungicide formulation N1E to control gray mold disease of plants, was investigated to study the bacterial traits that may be involved in its biological control activity. Two N1E based formulations, bacterial cell based formulation PN1E and culture supernatant based formulation SN1E, were evaluated for disease control activity against gray mold disease of tomato and strawberry plants. Neither PN1E nor SN1E was as effective as the original formulation N1E. Fractionation of antifungal compounds from the bacterial culture supernatant of B. licheniformis N1 indicated that two different cyclic lipopeptides were responsible for the antimicrobial activity of the N1 strain. These two purified compounds were identified as iturin A and surfactin by HPLC and LCMS. The purified lipopeptides were evaluated for plant disease control activity against seven plant diseases. Crude extracts and purified compounds applied at 500 ${\mu}g/ml$ concentration controlled tomato gray mold, tomato late blight and pepper anthracnose effectively with over 70% disease control value. While iturin showed broad spectrum activity against all tested plant diseases, the control activity by surfactin was limited to tomato gray mold, tomato late blight, and pepper anthracnose. Although antifungal compounds from B. licheniformis N1 exhibited disease control activity, our results suggested that bacterial cells present in the N1E formulation also contribute to the disease control activity together with the antifungal compounds.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1999년도 정기총회 및 춘계 학술발표회
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• pp.26.3-27
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• 1999