• Mycobiology
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• v.30 no.2
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• pp.102-104
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• 2002

In July 2001, a destructive stem rot of tatarian aster(Aster taturicus) was occurred sporadically in exhibition farm of Gyeongsangnam-do Agricultural Research and Extension Services, in Hamyang, Korea. The fungus also caused collar and crown rot and systemic wilt or blight of whole plant. White mycelium spread over stems and petioles of infected plants and sclerotia formed on the old lesions and near the soil surface. The fungus showed maximum mycelial growth was obtained around $30^{\circ}C$ but did not grow below $5^{\circ}C$ or above $45^{\circ}C$. The mycelial width ranges $4.2{\sim}10.4{\mu}m$. and the color is white, usually many narrow mycelial stand grow in the aerial mycelium and formed clamp connection. Numerous sclerotia were formed in artificial media like PDA at $30^{\circ}C$. The shape of sclerotia were sphere and $1.0{\sim}3.2{\mu}m$ in diameter. The fungus was isolated repeatedly from the infected, tissues and confirmed its pathogenecity to aster and identified as Sclerotium rolfsii. This is the first report that Sclerotium rolfsii causes stem rot of tatarian aster in Korea.

• Mycobiology
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• v.32 no.3
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• pp.128-133
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• 2004

Twenty plant extracts were tested against mycelial growth, sclerotium formatiom and dry weight of mycelium with sclerotia of Sclerotium rolfsii Sacc. The highest(90 mm) mycelial growth was measured in Adhatoda vasica, Tegetes erecta, Allium cepa, and Curcuma longa. The lowest(25 mm) was in Azadirachta indica. No mycelial growth was found in any concentration of cow, buffalo, and goat urine. The highest(90 mm) and the lowest(15 mm) mycelial growth were measured in Biomil and Urea, respectively. No mycelial growth was observed in Zinc. The highest(60 mm) and the lowest(2 mm) mycelial growth were recorded in Macuprex(Dodine; 65% WP) and Boron(100% Boric acid and 17% Boron) respectively. Mycelial growth was totally inhibited in Rovral(Iprodione; 50% WP).

• Research in Plant Disease
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• v.17 no.3
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• pp.399-401
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• 2011

Stem rot of Stachys sieboldii occurred sporadically in the farmer's fields at Shindeung-myeon, Sancheonggun, Gyeongnam province in Korea. The infected leaves and stems are water-soaked, rotted, wilted and finally leads to the death of the whole plants. The sclerotia, 1-3 mm, white to brown, globoid, were formed on lesions and the surface of soil line. The optimum temperature for mycelial growth and sclerotia formation was $30^{\circ}C$ on potato dextrose agar. The typical clamp connections were observed in the hyphae of the fungus. 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 S. sieboldii caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.17 no.2
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• pp.225-227
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• 2011

The stem rot of Chrysanthemum zawadskii var. latilobum occurred in the landscape field of Sanggwan-myeon, Wanju-gun, Jeonbuk, Korea in September 2009. The typical symptoms of the disease were water-soaking and dark brown rot on the stem, wilting and blighting. Most infected plants died of the disease. White mycelial mats were spread over lesions and brown sclerotia were formed on stems and near soil surface. The sclerotia were spherical or irregular, 0.8-3.5 (mean 1.8) mm in size on potato dextrose agar, brown in color. The optimal temperature range of hyphal growth was $25-30^{\circ}C$ and the hyphal diameter was 4-9 ${\mu}m$. Clamp connections were observed in the hyphae of the fungus grown on potato dextrose agar. Pathogenicity of the casual organism was provided on C. zawadskii according to Koch's postulate. The fungus was identified as Sclerotium rolfsii on the basis of mycologiclal characteristics and pathogenicity test to host plants. This is the first report on the stem rot of C. zawadskii caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.15 no.1
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• pp.51-53
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• 2009

The fruit rot of watermelon (Citrullus lanatus) occurred sporadically in the farmers field at Chojeondong, Jinju city, Korea, in 2007. The typical symptom was water-soaked, brown on the fruit, and than infected fruits were mostly rotted. White mycelial mats were spread over lesions, and then sclerotia were formed on fruit and near soil line. The sclerotia were globoid in shape, $1{\sim}3\;mm$ in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$ and the hyphal width was $4{\sim}8{\mu}m$. The typical clamp connections were observed in the hyphae of the fungus. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii. This is the first report on the fruit rot of watermelon by S. rolfsii 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.

• Research in Plant Disease
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• v.12 no.1
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• pp.55-57
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• 2006

Stem rot of Houttuynia cordata occurred in the experiment field of Research Institute of Natural Product, Uiseong, Gyeongbuk, Korea in July 2003. The typical symptoms of the disease were water-soaking, stem rot, necrotic tuber. White mycelial mats were spread over lesions and sclerotia were formed on died plant and near soil line. The sclerotia were spherical and irregular, 1-2.5 mm on potato dextrose agar (PDA), white to brown in color, The optimal temperature for hyphal growth was $28{\sim}30^{\circ}C$ and the hyphal diameter was $3{\sim}9{\mu}m$. Clamp connections were observed on PDA. Pathogenicity of the casual organism was provided on H. cordata according to Koch's postulate. The fungus was identified as Sclerotium rolfsii Saccardo on the basis of mycological characteristics and pathogenicity test to host plants. This is the first report on the stem rot of H. cordata caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.11 no.2
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• pp.201-203
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• 2005

The stem rot disease was found on Hosta longipes that planted in the flower beds along the Namgang riverside in Jinju city, Korea. The disease occurred first time in July, 2004 and sporadically occurred in 2005. The typical symptom of the disease is water-soaking, dark brown spot on the stem, and getting wilt. 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 in shape, $1\~3$ mm in diameter and white to brown in color, The optimum temperature for mycelial growth of the fungus on PDA was $30^{\circ}C$ and the hyphal width was $4\~8{\mu}m$. Clamp connections were observed in the hyphae of the fungus grown on PDA. Pathogenicity of the causal organism was proved on Hosta longipes according to Koch,s postulate. On the basis of mycological characteristics and pathogenicity to host plants, the fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the stem rot of H. longipes caused by S. rolfsii in Korea.

• The Korean Journal of Mycology
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• v.40 no.3
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• pp.177-178
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• 2012

Stem rot of perilla (Perilla frutescens var. japonica Hara) occurred sporadically in the exhibition field at Gyeongsangnam-do Agricultural Research and Extension Services in Korea. The infected stems are water-soaked, rotted, wilted and finally leads to the death of the whole plants. The sclerotia, 1-3 mm, white to brown, spherical, were formed on lesions and the surface of soil line. The optimum temperature for mycelial growth and sclerotia formation was $30^{\circ}C$ on potato dextrose agar and the hyphal width was 4-9 ${\mu}m$. The typical clamp connections were observed in the hyphae of the fungus. 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 perilla caused by S. rolfsii in Korea.

• The Korean Journal of Mycology
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• v.39 no.2
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• pp.145-147
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• 2011

Stem rot symptoms of Convallaria keiskei occurred sporadically in the herb exhibition field at Hamyang-gun Gyeongnam province in Korea. The typical symptom is water-soaking on the main stem, rotting, wilting, and blighting, which eventually leads to death of the plant. The sclerotia, which were white to brown in color, globoid in shape with size of 1~3 mm hyphal width of which was 4~9 ${\mu}m$, 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 Convallaria keiskei caused by S. rolfsii in Korea.