• Research in Plant Disease
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• v.11 no.1
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• pp.85-87
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• 2005

In July 2003, a destructive stem rot occurred sporadically in an exhibition farm on Aster glehni of Hamyanggun, Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The typical symptoms of the disease were water-soaking, stem rot, wilt or blight. The infected plants were mostly died. White mycelial mats were spread over lesions and sclerotia were formed on stems and near soil line. The sclerotia were globoid or irregular in shape, 1~3 mm in size, and white to brown in color. The optimum temperature for fungal growth was about 30oC. Clamp connections were observed in the hyphae of the fungus grown on potato dextrose agar, and hyphal diameter was 3~8 ${\mu}m$. On the basis of mycological characteristics and test of pathogenicity to host plants, the fungus was identified as Sclerotium rolfsii. This is the first report on the stem rot of Aster glehni caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.18 no.2
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• pp.139-141
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• 2012

Stem rot symptoms of common bean occurred sporadically in Jinju, Korea. The typical symptom included water-soaking on the main stem, rotting, wilting, and blighting, which eventually leads to death of the plant. The sclerotia, white to brown, spherical with size of 1-3 mm, formed over lesions and surface soil line. The optimum temperature for mycelial growth and sclerotia formation was $30^{\circ}C$ on potato dextrose agar (PDA). The typical clamp connections were observed in the hyphae of the fungus grown on PDA. Mycological characteristics and pathogenicity to host plants indicated that the fungus was Sclerotium rolfsii Saccardo. This is the first report of stem rot on common bean caused by S. rolfsii in Korea.

• The Korean Journal of Mycology
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• v.28 no.1
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• pp.46-48
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• 2000

The gray mold disease was severely occurred on safflower grown in experimental farm of Kyongsangnam-do Agricultural Research and Extension Services in 1999. At first, the infected leaves discolored gray or dark from the tip and gradually expanded to downword. The fungus also attacked stem, pod and calyx. The infected area became dark and dried, and frequently gray mold grown on the infected area. The causal organism was isolated and proved its pathogenecity according to Koch's postulate. Conidia of the fungus in mass were hyaline or gray, 1-celled, mostly ellipsoid or ovoid and sized $7.4{\sim}16.8{\times}5.3{\times}10.4\;{\mu}m$. Conidiophores were observed with their wide size of $2.9{\times}15.5\;{\mu}m$. The temperature range for mycelial growth was between $5^{\circ}C\;and\;30^{\circ}C$ with the optimum temperatures of $20^{\circ}C\;and\;25^{\circ}C$. The causal organism was identified as Botrytis cinerea and based on mycological characteristics examined. This is the first report on gray mold of safflower caused by Botrytis cinerea in Korea.

• Mycobiology
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• v.28 no.1
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• pp.54-56
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• 2000

A black scab disease occurred on sword bean (Canavalia gladiata) in plastic film houses around Chinju area during the spring season of 1999. The disease started from flower bud, then moved to flower stalk, pod, petiole, cirrus, stem and leaves. The lesions started with small dark brown spots then were gradually expanded. Severely infected plants reached 37.4% of whole plant covered with scab. Numerous conidia were produced on the diseased flower disk, pod, floral axis, stem and leaves. Most of the conidia were appeared to be readily dispersed in the air, but the mycelia were not suggested causing of sooty mold by ectoparasitism. A fungus was isolated from the diseased stem, and inoculated to healthy plants to satisfy the Koch's postulates and proved the fungus was the causal agent of the disease. The isolated fungus grew on potato dextrose agar, forming greenish black to pale brown colonies. Conidia were ellipsoidal, fusiform or subspherical, mostly one-celled but occasionally septated. The conidia were $3.9{\sim}34.1{\times}2.7{\sim}5.1\;{\mu}m$ in size and formed in long branched chains on the erected conidiophores which were pale olivaceous brown and variable in length between $7.2{\sim}210.7\;{\mu}m$ in size. Ramoconidia were $7.6{\sim}29.2{\times}3.2{\sim}14.4\;{\mu}m$ in size. The fungus was identified as Cladosporium cucumerinum based on the above morphological characteristics. The optimum temperature for mycelial growth and conidial formation was about 15 to $25^{\circ}C$. Cladosporium scab of sword bean caused by the fungi has not been reported in Korea previously.

• Research in Plant Disease
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• v.14 no.1
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• pp.61-63
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• 2008

Anthracnose of blueberry (Vaccinium spp.) caused by Colletotrichum gloeosporioides was observed in the exhibition orchard of Gyeongsangnam-do Agricultural Research and Extension Services in Korea, 2007. The typical symptoms were initially water-soaked lesions and then rotten on fruits, the infected fruits were dropped but some of them were hunged and mummified. The pathogenic fungus grown on potato dextrose agar showed greyish to dark gray color. Conidia were straight, cylindrical apex obtuse in shape and $10{\sim}20{\times}3{\sim}5\;{\mu}m$ in size. Appressoria were brown in color, clavate or ovate in shape and $6{\sim}18{\times}4{\sim}12\;{\mu}m$ in size. Optimum temperature for mycelial growth was $25{\sim}30^{\circ}C$. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Colletotrichum gloeosporioides (Penz.) Penz. & Sacc.. This is the first report on the anthracnose of blueberry (Vaccinium spp.) caused by C. gloeosporioides in Korea.

• Research in Plant Disease
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• v.12 no.2
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• pp.119-121
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• 2006

Anthracnose of pomegranate (Punica granatum) caused by Colletotrichum acutatum was observed in the exhibition field at Hamyang-gun, Gyeongsangnam-do Agricultural Research and Extension Services, and in farmer's orchard at Gaheo-myon, Hapcheon-gun, Gyeongnam province, Korea. The pathogen generally attacks on the fruits and induces dark lesion and rotting. The infected fruits were mostly dropped or mummified. The color of colonies of the pathogenic fungus grown on potato dextrose agar was pinkish gray. Conidia were fusiform in shape and was $8{\sim}16{\times}3{\sim}4{\mu}m$ in size. Appressoria were pale to dark brown in color, clavate in shape and was $8{\sim}12{\times}4{\sim}6{\mu}m$ in size. Optimum temperature for mycelial growth was $25^{\circ}C$. Pathogenicity of the causal organism was proved according to Koch's postulate. On the basis of mycological characteristics and pathogenicity test on fruit, the fungus was identified as Colletotrichum acutatum. This is the first report on the anthracnose of pomegranate caused by C. acutatum in Korea.

• Research in Plant Disease
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• v.16 no.1
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• pp.90-93
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• 2010

Sclerotinia rot occurred sporadically on the stems and leaves of Astragalus sinicus in the farmers fields at Goseong-gun, Gyeongnam province in Korea. The infected plants showed the typical symptoms: watersoaked, wilt, rot, blight and eventual death. The colony of the isolated fungus on potato-dextrose agar (PDA) was white to faintly gray color. Sclerotia formed on the PDA were globose in shape, black in color and $2{\sim}14{\times}2{\sim}7mm$ in size. The optimum temperature for mycelial growth and sclerotium formation was at $20^{\circ}C$ on PDA. Apothecia formed on PDA were globose~disk in shape and 3~8 mm in size. Asci were cylindrical in shape and $145{\sim}210{\times}10{\sim}12{\mu}m$ in size. Ascospores were ellipsoid and $10{\sim}14{\times}6{\sim}7{\mu}m$ in size. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Sclerotinia trifoliorum Eriksson. This is the first report on sclerotinia rot of A. sinicus caused by Strifoliorum Eriksson in Korea.

• The Korean Journal of Mycology
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• v.40 no.2
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• pp.124-126
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• 2012

Stem rot symptoms of Eupatorium lindleyanum occurred sporadically in the herb exhibition field at Hamyang-gun Gyeongsangnam-do Agricultural Research and Extension Services in Korea. The typical symptom included water-soaking on the main stem, rotting, wilting, and blighting, which eventually leads to death of the plant. The sclerotia, white to brown, globoid with size of 1-3 mm, were formed over lesions and surface soil line. The optimum temperature for mycelial growth and sclerotia formation was $30^{\circ}C$ on PDA. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. Mycological characteristics and pathogenicity to host plants indicated that the infected fungus was Sclerotium rolfsii Saccardo. This is the first report of stem rot on Eupatorium lindleyanum caused by S. rolfsii in Korea.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.254-255
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• 2011

Stem rot symptoms of Euphorbia marginata were occurred in the herb exhibition field at Gyeongsangnam-do Agricultural Research and Extension Services in Korea. The typical symptom was started with watersoaking lesion on the stem then gradually rotted, wilted, and blighted, the severely infected plants were eventually died. The sclerotia of the pathogen were globoid in shape, 1~3mm in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$. The hyphal width was 4~9 ${\mu}m$, and the typical clamp connection structures were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report of stem rot on E. marginata caused by S. rolfsii in Korea.

• The Korean Journal of Mycology
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• v.34 no.2
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• pp.122-124
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• 2006

In March of 2005, gray mold disease caused by Botrytis cinereu on Stachys sieboldii Miq. was occurred in the mud cellar storage of Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The symptoms started with water-soaked and rotten in the tubers. The conidia were one celled and mostly ellipsoid or ovoid in shape and light gray in color. The conidia were $5{\sim}16{\times}4{\sim}12{\mu}m$ in size and the conidiophores were $14{\sim}30{\mu}m$ in length. The pathogen formed conidia and sclerotia abundantly on PDA. The optimal temperature for mycelial growth and sclelotia formation was $20^{\circ}C$. On the basis of symptom, mycological characteristics and pathogenicity test on host plants, the fungus was identified as Botrytis cinerea Persoon: Fries. This is the first report on gray mold of S. sieboldii caused by B. cinerea in Korea.