• Journal of Microbiology and Biotechnology
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• 제16권3호
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• pp.465-468
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• 2006

Even though many pesticides are known for barley powdery mildew and wheat leaf rust, alternative controls are necessary, because of consumer rejection of chemical pesticides and the appearance of fungi resistant to fungicides. To discover biopesticides, many broths of microorganisms were screened. Of those, a culture broth of Burkholderia ambifaria showed an excellent antifungal activity against both Erysiphe graminis and Puccinia recondita, which cause barley powdery mildew and wheat leaf rust, respectively.

• 한국식물병리학회지
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• 제11권4호
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• pp.380-382
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• 1995

Yellow spot or blotch symptoms on the upper surface of leaf, without the production of velvet-like fungi on the lower surface of leaf as in the gray mold of tomato caused by Cladosporium fulvum, were observed in tomato (cv. Seokwang) plants in May, 1995, in a vinyl-house of the experimental plot of Gyeongnam Provincial Rural Development Administration, Chinju, Gyeongnam, Korea. We identified this disease as powdery mildew of tomato caused by Oidiopsis taurica (L v.) Arnaud (=Leveillula taurica), which was new to Korea. Conidia of the fungus were borne on uni- or bi-septated conidiophores which were developed through the stomata of the tomato leaf. The conidia were slender, clavate and variable in size (31~111.6$\times$13.1 ${\mu}{\textrm}{m}$). The fungal conidia isolated from tomato leaves were inoculated to tomato plants, and the occurrence of the same disease was confirmed based on the symptomatology and the morphology of the pathogen reisolated.

• 식물병연구
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• 제15권1호
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• pp.23-29
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• 2009

2005년부터 2007년까지 3년 동안 경상남도농업기술원 시설하우스와 유리온실에 재배중인 가지, 파프리카, 토마토에 발생하는 흰가루병을 방제하기 위하여 친환경 농자재인 난황유를 살포한 것과 난황유에 칼슘과 님오일을 혼합한 제제를 살포한 후 병 방제효과와 식물체 상에서 병원균의 형태적 변화를 관찰하였다. 채종유로 만든 난황유를 5일 간격으로 3회 지상부에 골고루 살포하고 최종약제 살포 후 5일째 병 진전을 조사한 경우 가지 흰가루병이 94.6% 방제가 되었고, 파프리카 흰가루병은 난황유만을 살포한 경우에는 91.6%의 방제가를 나타내었으며, 난황유에 칼슘과 님오일을 혼합하여 살포할 경우 96.2%의 더 높은 방제가를 나타내었다. 시설하우스내 토마토(방울, 완숙) 철가루병 방제를 위해 채종유로 만든 난황유를 살포할 경우 91.1$\sim$91.7% 정도 방제 되었으며, 난황유와 칼슘과 님오일을 혼합하여 살포할 경우 100% 방제가 되었다. 난황유를 처리하지 않은 식물체 표면에서는 건강하고 왕성한 균사, 분생포자경, 분생포자들을 전자현미경으로 관찰할 수 있었으나, 난황유를 처리한 이후에 관찰된 흰가루병균은 기주식물과 병원균의 종류에 관계없이 모두 세포벽이 파괴되어 원형질이 빠져나가 균사가 모두 쭈그러들었으며 분생포자가 생성되지 않았다.

• 한국균학회지
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• 제29권2호
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• pp.116-122
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• 2001

흰가루병에 대하여 생물적 방제제로 선발된 Ampelomyces quisqualis94013(AQ94013)의 포자현탁액을 처리하여 오이 흰가루병균(Sphaerotheca fuliginea)에 대한 침입과정을 전자현미경과 광학현미경으로 관찰한 결과, 포자현탁액 처리 후 4시간 만에 포자가 흰가루병균의 분생포자, 분생자경 및 균사위에서 발아하고, 17시간 후에는 유사부착기가 형성되어 흰가루병균의 균사에 부착되었다. 24시간 후에는 균사내에 침입하였으며, 44시간 후에는 흰가루병균의 균사와 분생자경의 하부에 AQ94013의 병자각이 형성되기 시작했다. 48시간 후에는 병자각이 성숙되었으며, 52시간 후에는 병자각의 공구에서 병포자가 분출되고, 흰가루병균의 균사 및 분생자경은 변형되어 죽었다. 한편, 오이흰가루병균에 대하여 A. quisqualis 94013의 배양여액을 농축하여 처리한 결과에서 물처리와 차이가 없었으므로 흰가루병균에 대한 감염기작은 A. quisqualis 94013가 독소생성에 의한 것이 아니라 직접기생에 의하여 흰가루병균을 죽이는 것으로 판단된다.

• Mycobiology
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• 제33권2호
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• pp.97-103
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• 2005

Crude extracts and active principles from medicinal plants have shown potential role in controlling plant diseases in glasshouses as well as in fields as one of the safest and ecofriendly methods. The effect of nor-securinine (an alkaloid) isolated from Phyllanthus amarus has been seen against spore germination of some fungi (Alternaria brassicae, A. solani, Curvularia pennisetti, Curvularia sp., Erysiphe pisi, Helminthosporium frumentacei) as well as pea powdery mildew (Erysiphe pisi) under glasshouse conditions. The sensitivity of fungi to nor-securinine varied considerably. Nor-securinine was effective against most of the fungi. H. frumentacei was more sensitive even at the lowest concentration ($1,000\;{\mu}g/ml$). Likewise conidia of E. pisi were also inhibited in partially or completely appressorium formation. Pre-inoculation treatment showed greater efficacy than post-inoculation in inhibiting powdery mildew development on pea plants in a glasshouse. Maximum inhibition occurred at $2000\;{\mu}g/ml$.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1995년도 Proceedings of special lectures on Molecular Biological Approaches to Plant Disease National Agricultural Science and Technology Institute Suwon, Korea
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• pp.27-53
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• 1995

In plant pathology there is an increasing necessity for improved cytological techniques as basis for the localization of cellular substances within the dynamic fine structure of the host-(plant)-pathogen-interaction. Low temperature (LT) preparation techniques (shock freezing, freeze substitution, LT embedding) are now successfully applied in plant pathology. They are regarded as important tools to stabilize the dynamic plant-pathogen-interaction as it exists under physiological conditions. - The main advantage of LT techniques versus conventional chemical fixation is seen in the maintenance of the hydration shell of molecules and macromolecular structures. This results in an improved fine structural preservation and in a superior retention of the antigenicity of proteins. - A well defined ultrastructure of small, fungal organisms and large biological samples such as plant material and as well as the plant-pathogen (fungus) infection sites are presented. The mesophyll tissue of Arabidopsis thaliana is characterized by homogeneously structured cytoplasm closely attached to the cell wall. From analyses of the compatible interaction between Erysiphe graminis f. sp. hordei on barley (Hordeum vulgare), various steps in the infection sequence can be identified. Infection sites of powdery mildew on primary leaves of barley are analysed with regard to the fine structural preservation of the haustoria. The presentation s focussed on the ultrastructure of the extrahaustorial matrix and the extrahaustorial membrane. - The integration of improved cellular preservation with a molecular analysis of the infected host cell is achieved by the application of secondary probing techniques, i.e. immunocytochemistry. Recent data on the characterization of freeze substituted powdery mildew and urst infected plant tissue by immunogold methodology are described with special emphasis on the localization of THRGP-like (threonine-hydrxyproline-rich glycoprotein) epitopes. Infection sites of powdery mildew on barley, stem rust as well as leaf rust (Puccinia recondita) on primary leaves of wheat were probed with a polyclonal antiserum to maize THRGP. Cross-reactivity with the anti-THRGP antiserum was observed over the extrahaustorial matrix of the both compatible and incompatible plant-pathogen interactions. The highly localized accumulation of THRGP-like epitopes at the extrahaustorial host-pathogen interface suggests the involvement of structural, interfacial proteins during the infection of monocotyledonous plants by obligate, biotrophic fungi.

• 식물병연구
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• 제12권1호
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• pp.51-54
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• 2006

4종류의 식물 추출 오일(마늘, 생강, 계피, 레몬그라스)에 대한 실내 항균효과를 5종의 식물병원세균과 4종의 식물병원진균에 대해 조사하였다. 4종의 오일중 마늘오일과 계피오일의 항균효과가 우수하였다. 특히, 마늘오일은 식물병원세균인 Agrobacterium tumefaciens, Erwinia carotovora, Ralstonia solanacearum, Xanthomonas campestris와 식물병원진균인 Phytophthora infestans, Fusarium oxysporum, Collectotricum sp.에 대해 강한 항균력을 나타내었다. 그러나, Acidovorax avenae와 Pythium sp.에 대해서는 항균효과가 없었다. 마늘오일의 오이 흰가루병(Sphaerotheca fusca)과 토마토 흰가루병(Erysiphe cichoracearum)에 대한 포장 방제효과 실험결과 각각 70.0-74.6%와 71.2%의 방제가를 나타내었다.

• 한국균학회지
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• 제48권3호
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• pp.337-343
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• 2020

한국에서 식물병원성 균류의 생물다양성을 파악하기 위한 균류 탐사를 통하여 에키나시아 흰가루병이 지속적으로 관찰되었다. 총 9점의 시료를 고려대학교 식물표본보관소에 보존하였다. 병든 식물에서는 주로 성엽에서 흰색의 얇은 균사층이 전면으로 또는 부분적으로 나타났다. 흰가루병균의 감염으로 줄기와 꽃잎에서는 변색 부위가 나타나는 특징을 보였다. 이 흰가루병균 무성세대의 형태적 특징과 더불어 ITS 및 LSU 염기서열을 계통분석한 결과, 이 흰가루병균은 Podosphaera xanthii로 동정되었다. 이는 한국에서 에키나시아 흰가루병에 관한 최초의 보고이다.

• 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)

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1994년도 Proceedings of International Symposium on BIOLOGICAL CONTROL OF PLANT DISEASES Korean Society of Plant Pathology
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• pp.50-61
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• 1994

Biological control of important fungal diseases such as Phytophthora blight of red pepper, gary mold rot of vegetables, and powdery mildew of many crops was attempted using an antagonistic bacterium, Bacillus sp. AC-1 in greenhouses and fields. The antagonistic bacterium isolated from the rhizosphere soils of healthy red pepper plant was very effective in the inhibition of mycelial growth of plant pathogenic fungi in vitro including Phytophthora capsici, Rhizoctonia solani, Pyricularia oryzae, Botrytis cinerea, Valsa mali, Fusarium oxysporum, Pythium ultimum, Alternari mali, Helminthosporium oryzae, and Colletotrichum gloeosporioides. Culture filtrate of antagonistic Bacillus sp. AC-1 applied to pot soils infested with Phytophthora capsici suppressed the disease occurrence better than metalaxyl application did until 37 days after treatment in greenhouse tests. Treatments of the bacterial suspension on red pepper plants also reduced the incidence of Phytophthora blight in greenhouse tests. In farmers' commercial production fields, however, the controlling efficacy of the antagonistic bacteria was variable depending on field locations. Gray mold rot of chinese chives and lettuce caused by Botrytis cinerea was also controlled effectively in field tests by the application of Bacillus sp. AC-1 with control values of 79.7% and 72.8%, respectively. Spraying of the bacterial suspension inhibited development of powdery mildew of many crops such as cucumber, tobacco, melon, and rose effectively in greenhouse and field tests. The control efficacy of the bacterial suspension was almost same as that of Fenarimol used as a chemical standard. Further experiments for developing a commercial product from the antagonistic bacteria and for elucidating antagonistic mechanism against plant pathogenic fungi are in progress.