• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.599-606
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• 2004

Gram-positive antagonistic bacilli were isolated from agricultural soils for possible use in biocontrol of plant pathogenic fungi, Fusarium oxysporum, Rhizoctonia solani, and/or Pythium ultimum. Among the 65 antagonistic Gram-positive soil isolates, 22 strains were identified as Bacillus species by 16S rDNA sequence analyses. Four strains, including DF14, especially exhibited multiple antagonistic properties against the three damping-off fungi. Genotypic properties of the Bacillus isolates were characterized by rapid molecular fingerprinting methods using repetitive extragenic palindromic-PCR (REP-PCR), ribosomal intergenic spacer-length polymorphisms (RIS-LP), 16S rDNA PCR-restriction fragment length polymorphisms (PCR-RFLP), and strain-specific PCR assays. The results indicated that the REP-PCR method was more valuable than the RIS-LP and 16S rDNA PCR-RFLP analyses as a rapid and reliable approach for bacilli typing and identification. The use of strain-specific primers designed based on 16S rDNA sequence comparisons enabled it to be possible to selectively detect a strain, DF14, which is being used as a biocontrol agent against damping-off fungi.

• 농약과학회지
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• 제19권1호
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• pp.71-79
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• 2015

국내에서 서식하는 10종의 곤충에서 분리한 49균주의 장내세균으로 7종의 주요한 식물병원성 곰팡이에 대하여 항균활성을 검토하였다. 49개의 균주들은 담배장님노린재(Nesidiocoris tenuis)에서 Cedecea sp. 포함 4균주, 사슴벌레붙이(Odontotaenius disjunctus)에서 Enterobacter sp. 포함 3균주, 흰개미(Reticulitermes speratus)에서 Acinetobacter sp. 포함 4균주, 톱다리개미허리노린재(Riptortus clavatus)에서 Clavibacter sp. 포함 4균주, 열점박이잎벌레(Lema decempunctata)에서 Bacillus sp. 포함 11균주, 이십팔점박이무당벌레(Henosepilachna vigintioctopunctata)에서 Enterococcus sp. 포함 3균주, 무당벌레(Harmonia axyridis)에서 Staphylococccus sp. 포함 2균주, 콩풍뎅이(Popillia mutans)에서 Enterobacter asburiae 균을 포함한 5균주, 물땡땡이(Hydrophilus acuminatus)에서는 Aeromonas sp. 포함 7균주가 팔맥풍뎅이(Anomala octiescostata)에서는 Brucella sp. 를 포함한 7균주 등이 분리, 동정되었다. 이 49균주를 항균활성을 측정하기 위해 7종의 식물병원성 곰팡이인 토마토겹둥근무늬병(A. solani), 고추탄저병(C. gloeosporioides), 잿빛곰팡이병(B. cinerea), 시들음병(F. oxysporum), 고추역병(P. capsici), 벼문고병(R. solani), 상추균핵병(S. sclerotiorum)과 함께 PDA배지에서 대치 배양한 결과, A. solani에 대하여 항균활성을 갖는 26균주, B. cinerea에 항균활성을 갖는 6균주, C. gloeosporioides에 항균활성을 갖는 13균주, F. oxysporum에 항균활성을 갖는 11균주, P. capsici에 항균활성을 갖는 17균주, R. solani에 항균활성을 갖는 2균주와 S. sclerotiorum에 대하여 항균활성을 갖는 2균주로 나타났다. 항균활성의 결과 7종의 모든 식물병원성 곰팡이에 항균활성을 갖는 Pseudomonas aeruginosa를 선발하였다. 생물활성은 고추에 직접 분무 및 접종 처리하였을 때 고추 탄저병균(C. gloeosporioides)에 대하여 항균효과가 뚜렷하게 나타나는 것으로 확인되었다.

• 한국식물병리학회지
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• 제14권4호
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• pp.345-349
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• 1998

Fifty isolates of myxobacteria were isolated from soils from several areas in Korea during 1996-1997 and bioactivity against plant pathogenic fungi of these isolates was examined. A myxobacterial isolate KR025 showed good antifungal activities against Pyricularia oryzae, Cryphonectria parasitica, Colletotrichum lagenarium, and C. gloeosporioides but did not against Rhizoctonia solani, Fusarium oxysporum and Pythium ultimum. The bacterium was identified as Myxococcus fulvus based on morphological and physiological characteristics. Antifungal substances were extracted from culture broth and bacterial cell of Myxococcus fulvus KR025 by ethyl acetate. Antifungal substance of Myxothiazole (100 ${\mu}{\textrm}{m}$/ml) produced by Myxococcus fulvus KR 025 controlled 97.0% rice blast, tomato late blight, wheat leaf rust, and barley powdery mildew and showed 45.0 and 82.6% disease control of rice sheath blight and cucumber gray model, respectively.

• 농업과학연구
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• 제49권1호
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• pp.121-128
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• 2022

Fusarium wilt disease caused by Fusarium species is a major problem affecting cultivated cucurbit plants worldwide. Fusarium species are well-known soil-borne pathogenic fungi that cause Fusarium wilt disease in several cucurbit plants. In this study, we aimed to identify and classify pathogenic Fusarium species from cultivated Korean cucurbit plants, specifically watermelon and cucumber. Thirty-six Fusarium isolates from different regions of Korea were obtained from the National Institute of Horticulture and Herbal Science Germplasm collection. Each isolate was morphologically and molecularly identified using an internal transcribed spacer of ribosomal DNA, elongation factor-1α, and the beta-tubulin gene marker sequence. Fusarium species that infect the cucurbit plant family could be divided into three groups: Fusarium oxysporum (F. oxysporum), Fusarium solani (F. solani), and Fusarium equiseti (F. equieti). Among the 36 isolates examined, six were non-pathogenic (F. equiseti: 15-127, F. oxysporum: 14-129, 17-557, 17-559, 18-369, F. solani: 12-155), whereas 30 isolates were pathogenic. Five of the F. solani isolates (11-117, 14-130, 17-554, 17-555, 17-556) were found to be highly pathogenic to both watermelon and cucumber plants, posing a great threat to cucurbit production in Korea. The identification of several isolates of F. equiseti and F. oxysporum, which are both highly pathogenic to bottle gourd, may indicate waning resistance to Fusarium species infection.

• 식물병연구
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• 제10권1호
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• pp.63-68
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• 2004

벼에서 문제시되는 도열병과 잎집무의마름병을 생물학적으로 방제하기 위해 병원균과 생태학적 지위가 비슷한 벼 뿌리에서 내생하는 S. marcescens 23 균주를 분리하였다. 선발 균주들을 공시하여 R. solani와 P. grisea에 대한 길항능력을 검정하여 R. solani와 P. grisea에 각각 83.9％. 88.3％의 높은 억제율을 보인 RSm220 균주를 선발하였다. 선발된 RSm220은 생리ㆍ생화학적 특성 검정결과 S. marcescens type strain과 높은 상관성을 나타내었고. 16S rDNA sequencing에 의한 계통 분석에 의해 S. marcescens의 16S rDNA sequence에 98.2％ 유사성을 나타내어 S. marcescens로 동정되었다 내생성 S. marcescens RSm220은 벼 도열병과 잎집무늬마름병에 대한 생물학적 방제제로의 사용이 가능할 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제15권1호
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• pp.112-117
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• 2005

Abstract Griseofulvin has been used as an antifungal antibiotic for the treatment of mycotic diseases of humans and veterinary animals. The purpose of this work was to identify a griseofulvin-producing endophytic fungus from Abies holophylla and evaluate its in vivo antifungal activity against plant pathogenic fungi. Based on nuclear ribosomal ITS1-5.8SITS2 sequence analysis, the fungus was identified and labeled as Xylaria sp. F0010. Two antifungal substances were purified from liquid cultures of Xylaria sp. F0010, and their chemical identities were determined to be griseofulvin and dechlorogriseofulvin through mass and NMR spectral analyses. Compared to dechlorogriseofulvin, griseofulvin showed high in vivo and in vitro antifungal activity, and effectively controlled the development of rice blast (Magnaporthe grisea), rice sheath blight (Corticium sasaki), wheat leaf rust (Puccinia recondita), and barley powdery mildew (Blumeria graminis f. sp. hordei), at doses of 50 to 150 ${\mu}$g/ml, depending on the disease. This is the first report on the production of griseofulvin and dechlorogriseofulvin by Xylaria species.

• 아시안잔디학회지
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• 제23권2호
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• pp.209-218
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• 2009

본 연구에서는 골프장에서 문제가 되는 주요 병의 방제가능한 생물학적 제제를 개발하기 위하여 실시하였다. 강원도 소재 골프장의 잔디 근권토양으로부터 채취한 100여개의 미생물로부터 4개의 길항 미생물을 선발하였다. 배지를 이용한 저지원 실험에서 4개의 균주는 한국 골프장에서 문제가 되고 있는 옐로우패취(Rhizoctonia cerealis), 브래운패취(R. solani AG-1(1B)), 동전마름병(Sclerotinia homoeocarpa), 그리고 설부갈색소립균핵병원균 (Typhula incarnata)에 대하여 효과적이었다. 옐로우패취, 브래운패취, 동전마름병을 대상으로 온실실험 결과, 4개의 균주는 병의 종류, 기주 식물체 및 병 발생 정도에 따라 효과가 달랐지만 한개 혹은 그 이상의 병에 대해 60% 이상을 방제가를 기록하였다. 4개의 균주는 생화학적 특성과 16S rRNA 분석을 통해 Pseudomonas spp.로 밝혀졌다. 현재 4개의 균주는 적정 배양조건과 제제화를 위한 연구 중에 있다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.131.2-132
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• 2003

White rot on garlic caused by Sclerotium cepivorum firstly occurred at Goheoung, Jeonnam in 1998. Thereafter, the disease rapidly spread throughout the country except Gangwon and became a major limiting factor for the cultivation of various Allium species such as garlic, onion, and welsh onion. The disease that has not been reported on a wild garlic(Allium monanthum) previously occurred severely at Seosan, Choongnam in 2003. Among cultivation areas in the region, 10.7％ were infected by the disease and the ratio of diseased plant reached up to 55.0％ in some heavily infected fields. Two species of Sclerotium were consistently isolated from infected samples and identified as S. cepivorum or another Sclerotium sp. Averaged size of sclerotium of the former was 455.0x562.2 urn, while the later was 374.4${\times}$347.2$\mu\textrm{m}$. Patogenicity to Allium species and mycological characteristics such as sclerotium size, growth temperature, and microconidia of the fungi were similar to those reported on other Allium species previously. Consequently, the wild garlic is a newly reported host of the two pathogenic fungi in Korea.

• The Plant Pathology Journal
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• 제25권1호
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• pp.70-76
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• 2009

The rhizobacteria of Panax notoginseng were isolated from six sites in Yanshan, Maguan and Wenshan Counties, Yunnan Province of China, and their antagonistic activity against P. notoginseng root-rot fungal pathogens was determined. Of the 574 rhizobacteria isolated, 5.8% isolates were antagonistic in vitro to at least one of the five pathogens, Cylindrocarpon didynum, Fusarium solani, Phytophthora cactorum, Phoma herbarum, and Rhizoctonia solani. The number of rhizo bacteria and the number that inhibited fungi differed depending on sampling sites and isolation methods. Rhizobacteria isolated from the site in Yanshan and Maguan showed more antagonistic effect than them in Wenshan. Heat treatment of rhizosphere soil at $80^{\circ}C$ for 20 min scaled the antagonists up to 14.0%. Antagonistic bacteria in the roots proportioned 3.9% of the total isolates. The most antagonistic isolates 79-9 and 81-4 are Bacillus subtilis based on their 168 rDNA sequence and biochemical and physiological characteristics. Identification and evaluation of antagonistic bacteria against P. notoginseng root-rot pathogens in the main planting areas improved our understanding of their distribution in rhizosphere soil. Furthermore these results indicated that the interactions between biocontrol agent and soil microbes should be seriously considered for the successful survival and biocontrol efficacy of the agents in soil.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.98.1-98
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• 2003

Antagonistic effect of bacterial strains isolated from phylloplane of strawberry plants grown In greenhouse was tested on Botrytis cinerea Among the promising bacterial strains, Bacillus sp. S1-0210 showed highest inhibition of mycelial growth of B. cinerea and a broad spectrum of antifungal activities against many plant pathogenic fungi in vitro. Bacillus sp. S1-0210 was identified as Bacillus subtilis based on the analysis of 185 rDNA as well as its biochemical characteristics. Application of wettable powder formulation of B. subtiiis S1-0210 significantly reduced the incidence of gray mold on trawberry fruits during storage. Results showed that treatment of B. subtilis S1-0210 decreased the incidence of gray mold by 4.8％ whereas the incidence in control was 77.9％, indicating that the formulation of B. subtilis S1-0210 will be practically applied on strawberry fruits as a biocontrol agent of gray mold during storage.