• Mycobiology
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• v.29 no.3
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• pp.154-159
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• 2001

Natural sclerotium formation in two species of Curvularia was observed. The sclerotia were spherical to elongated. The scanning electron microscopical observations of sclerotia revealed that the sclerotia were of two distinct layers of cells, outer loosely woven hyphae and inner contact layer of cells. Different lights, viz. red, blue, green, fluorescent or addition of culture filtrate of Sclerotium rolfsii in the medium did not affect sclerotium formation.

• Mycobiology
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• v.39 no.3
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• pp.230-232
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• 2011

In this study, we characterized sporadically occurring sclerotium rot caused by Sclerotium rolfsii in Chinese chive (Allium tuberosum Roth.) in farm fields in Sacheon, Korea. The initial symptom of the disease was water-soaked, which progressed to rotting, wilting, blighting, and eventually death. Further, mycelial mats spread over the lesions near the soil line, and sclerotia formed on the scaly stem and leaves. The sclerotia were globoid, 1~3 mm, and white to brown. The optimum temperature for growth and sclerotia formation on potato dextrose agar (PDA) was $30^{\circ}C$. The diameter of the hypae ranged from 4 to 8 ${\mu}m$. Clamp connection was observed on PDA medium after 5 days of incubation. Based on the mycological characteristics, internal transcribed spacer sequence analysis, and pathogenicity test, the causal agent was identified as Sclerotium rolfsii Saccardo. This is the first report of sclerotium rot in Chinese chive caused by S. rolfsii in Korea.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.119-121
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• 1999

A destructive collar rot of safflower occurred severely research farm of at Kyongsangnam-do Agricultural Research and Extension Services in 1999. Incidence of the disease at 3 fields in Chinju was ranged from 21.6 to 34.2% Upper parts of infected stems were mostly blighted and white mycelia were found on the lesions. The same fungus was isolated consistently from the infected tissues and confirmed its pathogenecity to safflower. The causal fungus of collar rot disease was identified as Sclerotium rolfsii by the examination of colony type sclerotium formation and pathogenicity test. This fungus also causes stem rot crown rot wilt or blight on the safflower. This is the first report on the collar rot of safflower caused by Sclerotium rolfsii in Korea.

• The Korean Journal of Mycology
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• v.5 no.2
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• pp.21-23
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• 1977

• Research in Plant Disease
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• v.16 no.3
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• pp.320-322
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• 2010

The Sclerotium blight was found on Neofinetia falcata at Yong-in city, Gyenggi-do, Korea. The symptom occurred low leaves yellowish and wilt of a whole plant. Severely infected plants were blighted and dies eventually. White mycelial mats appeared on the surface of basal stem and bulbs and the sclerotia were formed on stems, roots, and sphagnum moss. The sclerotia were spherical in shape, 1~3 mm in size and white to brown in color. The optimum temperature for the growth and sclerotia formation was $25{\sim}30^{\circ}C$ on PDA. On the pathogenicity test, the first symptom was appeared 5 days after inoculation and development to severe stem rot and blight. The causal fungus was identified as Sclerotium rolfsii and we suggested to call that the new Sclerotium blight on Neofinetia falcata caused by Sclerotium rolfsii in Korea.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.203-205
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• 2008

From 2006 to 2008, the stem rot of Petunia hybrida Vilm. caused by Sclerotium rolfsii occurred sporadically at Jinju city in Gyeongsangnam-do. The typical symptom is water-soaking, brown on the stem and rotting, wilting and blighting. The infected plants were mostly died. White mycelial mats were spread over lesions, and then sclerotia were formed on stem 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 was at $30^{\circ}C$ on PDA and the hyphal width ranged from 4 to $8{\mu}m$. The typical clamp connections were observed in the hyphae of the fungus. On the basis of mycological characteristics and pathogenicity to P. hybrida, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the stem rot of P. hybrida caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.17 no.3
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• pp.402-404
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• 2011

The Sclerotium blight was found on Phalaenopsis spp. at Dong-du-cheon city, and Hwa-seong city, Gyenggido, Korea in September 2009. The symptom included yellowing on lower leaves and wilt of a whole plant. Severely infected plants were blighted and died eventually. White mycelial mats appeared on the surface of basal stem and bulbs and the sclerotia were formed on stems, roots, and sphagnum moss. The sclerotia were spherical, 1-3 mm and white to brown. The optimum temperature for the growth and sclerotia formation was $25-30^{\circ}C$ on PDA. On the pathogenicity test, the first symptom appeared 5 days after inoculation and developed to severe stem rot and blight. On the basis of mycological characteristics and pathogenicity, the causal fungus was identified as Sclerotium rolfsii. This is the first report on the sclerotium blight on Phalaenopsis spp. caused by Sclerotium rolfsii in Korea.

• The Korean Journal of Mycology
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• v.44 no.1
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• pp.61-63
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• 2016

Sclerotium rot disease on cowpea (Vigna sinensis King) was observed in the exhibition field of Gyeongsangnam-do Agricultural Research and Extension Services in September 2015. Lesions were covered by white mycelial mats, and numerous sclerotia were formed on the stem near the soil line. The sclerotia were globoid in shape, 1~3 mm in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on potato dextrose agar (PDA) was $30^{\circ}C$, with the hyphal width of $4{\sim}8{\mu}m$. For molecular identification, the complete internal transcribed spacer (ITS) rDNA region of the causal fungus was sequenced and analyzed. Based on the mycological characteristics, ITS rDNA sequence analysis, and pathogenicity test, this fungus was identified as Sclerotium rolfsii. This is the first report of sclerotium rot on cowpea caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.17 no.2
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• pp.222-224
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• 2011

The sclerotium rot of onion (Allium cepa L.) was occurred sporadically in the farmer's fields at Daehap, Changnyeong in Korea. The typical symptom was water-soaking on the bulb, stem and leaves and then rotting, wilting, blighting and the infected plants eventually were rotted and died. The sclerotia were globoid, 1-3 mm, and white to brown. The optimum temperature for mycelial growth and sclerotial formation on PDA was $30^{\circ}C$. The hyphal width was 4-9 ${\mu}m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics, ITS rDNA sequence analysis, and pathogenicity, this fungus was identified as Sclerotium rolfsii Saccardo. To our knowledges, this is the first report of sclerotium rot on onion caused by S. rolfsii in Korea.

• The Korean Journal of Mycology
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• v.41 no.3
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• pp.197-199
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• 2013

The sclerotium rot of corn (Zea mays L.) occurred sporadically at the experimental field of Gyeongsangnam-do Agricultural Research and Extension Services in July 2011. The infected stems were water-soaked, wilted, and finally led to the death of the whole plants. White mycelial mats were spread over lesions, and then sclerotia were formed on stem and near soil line. The sclerotia were globoid in shape, white to brown in color and 1-3 mm in size. The hyphal width was $4-8{\mu}m$. The optimum temperature for mycelial growth and sclerotia formation on PDA was 30 on PDA. The typical clamp connections 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 sclerotium rot on corn caused by S. rolfsii in Korea.