• Research in Plant Disease
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• v.9 no.3
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• pp.162-165
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• 2003

High sporulation method and cultural characteristics of Cercospora capsici causing Cercospora leaf spot of pepper were examined. Optimum temperature for mycelial growth of Cercospora capsici was $25^{\circ}C$. The fungus did not grow below $5^{\circ}C$ and over $35^{\circ}C$. Optimum pH for mycelial growth was pH 4.0~pH 8.0. Mycelial growth was not influenced by light. C. capsici sporulated well on pepper leaf agar (5g/l). A standard method of sporulation established was as follows. The mycelial plugs were ground with some water in motar with pestle. The mycelial suspension was smeared on the surface of medium and incubated for 2~3 days at $20^{\circ}C$. The culture surface was lightly scraped with a brush after adding 1 ml of sterile water to stimulate sporulation and further incubated for 2~3 days.

• Research in Plant Disease
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• v.9 no.3
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• pp.166-169
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• 2003

Occurrence of cercospora leaf spot by Cercospora capsici is assamed to remarkbly cause the yield reduction through the leaf spot, yellowing of leaves and early defoliation in pepper cultivation. To develop resistant cultivar, optimal screening conditions of pepper against cercospora leaf spot were studied. Optimal screening conditions were 3.4 ${\times}$ $10^5$ conidia/ml conidial suspension were sprayed on to the leaves of 30~40 days old pepper seedlings, incubated at 15~$20^{\circ}C$/20~$25^{\circ}C$(day/night) and examined 20 days after inoculation.

• The Korean Journal of Mycology
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• v.12 no.2
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• pp.75-77
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• 1984

An undescribed Cercospora leaf spot of pepper grown in a greenhouse was observed at Jinju area in 1983. The symptom of this disease showed frog eyes spot on lower leaves of pepper. Leaves and petiole of pepper plant inoculated with spore suspension of this pathogen app­eared leaf spot after 2 weeks and exhibited cicular, brown frog eyes spot. This fungus was grown slowly on PDA and produce condia on infected leaves. The occurrence of this disease was responsi­ble for factors with high temperature and humidity conditions in the ill-ventilated greenhouse. This causal fungus was identified as Cercospora capsici Heald et. Wolf from the shape and length of the conidiophores, the length of the condia, and pathogenic behaviors.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.437-449
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• 1998

This paper is a fourth contribution towards taxonomic studies on Cercospora and allied genera, and contains ten species of Korean cercosporoid fungi; viz. Cercospora capsici, C. cardaminae, C. nasturtii, Phacellium episphaerium, Pseudocercospora chengtuensis, P. diospyrimorrisianae, Pseudocercosporella capsellae, Ramularia armoraciae, R. lamii var. lamii, and R. pratensis var. pratensis. Morphological characteristics of taxonomic value are described and drawn for these species to contribute towards a mycological monograph of Korean cercosporoid fungi.

• Journal of Microbiology and Biotechnology
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• v.5 no.6
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• pp.324-334
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• 1995

The actinomycete strain A 11 was antagonistic to plant pathogenic fungi Phytophthora capsid and Magnaporthe grisea. Based on the diaminopimelic acid (DAP) type and morphological characteristics examined by scanning electron microscopy, the strain A 11 was confirmed to belong to the genus Streptomyces. Based on Willcox probability and similarity level, the strain A 11 was numerically identified as Streptomyces flaveus using TAXON program of Ward and Goodfellow. Antibiotic production of S. flaveus strain A 11 was most favorable when cultured on glycerol yeast extract peptone (GYP) agar for 20 days at $28^{\circ}C$. The crude antibiotics from solid GYP agar cultures of the strain A 11 were most effective against Phytophthora capsici and Sclerotinia sclerotiorum among the fungi tested. Antifungal activity of the antibiotics against Alternaria solani, Botryosphaeria dothidea, Cercospora capsici, Magnaporthe grisea, and Rhizoctonia solani was somewhat high, whereas Colletotrichum gloeosporioides and Fusarium oxysporum f. sp. cucumerinum were rarely inhibited even at high concentrations.

• The Korean Journal of Mycology
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• v.14 no.1
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• pp.89-91
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• 1986

Sixteen seed samples of nine vegetable crops imported from Japan were tested for plant quarantine by routine methods of seed health testing. Nineteen species of fungi including Alternara alternata were identified from the seed samples. Some species were very frequently detected in the seeds. In this experiment, Verticillium albo-atrum, V. dahliae and Macrophomina sp. from the seeds of spinach, and Cercospora capsici, Drechslera hawaiiensis and V. albo-atrum from the seeds of sweet pepper were detected for the first time, respectively. It has been reported that they had a pathogenicity on some vegetable crops in Japan and other countries. The data suggest that an epidemic damage may be occurred if the infected seeds are sown and cultivated in Korea.

• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.191-202
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• 1998

About 300 actinomycetes were isolated from two forest and one sea-shore soil and tested for inhibitory effects on mycelial growth of six plant pathogenic fungi Magnaporthe grisea, Alternaria mali, Colletotrichum gloeosporioides, Phytophthora capsici, Fusarium oxysporum f. sp. cucumerinum, and Rhizoctonia solani. Among 300 actinomycetes tested, only 16 actinomycetes showed the antifungal activity against the test fungi. Isolate NH 50 was selected for production and purification of antifungal antibiotic substances. Actinomycete isolate NH 50 displayed the broad antifungal spectra against 11 plant pathogenic fungi. To identify actinomycete isolate NH 50, cultural characteristics on various agar media, diaminopimelic acid type, and morphological characteristics by scanning electron microscopy were examined. As a result, actinomycete isolate NH 50 was classified as a rare actinomycete that had LL-DAP type and did not produce spores. After incubation of isolate NH 50 in yeast extract-malt extract-dextrose broth, antifungal compound NH-B1 that inhibited mycelial growth of some plant pathogenic fungi was purified from the methanol eluates of XAD-16 resins by a series of purification procedures, i.e., silica gel flash chromatography, C18 flash chromatography, Sephadex LH-20 column chromatography, silica gel medium pressure liquid chromatography (MPLC), C18 MPLC, and high pressure liquid chromatography (HPLC). UV spectrum and 1HNMR spectrum of antifungal compound NH-B1 dissolved in methanol were examined. The antibiotic NH-B1 showed the major peaks at 230 and 271.2nm. Based on the data of 1H-NMR spectrum, NH-B1 was confirmed to be an extremely complex polymer of sugars called polysaccharides. The antibiotic NH-B1 showed strong antifungal activity against Alternaria solani and Cercospora kikuchi, but weak activity against M. grisea.