• The Plant Pathology Journal
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• v.23 no.4
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• pp.314-317
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• 2007

A soft stem rot disease was observed on Chamaecereus silvestrii (Korean name: Sanchui), a scion of graft-cactus, in major growing areas of Suwon (National Horticulture Research Institute), Anseong, Eumseong, Cheonan, Daegu, and Goyang, Korea during 2000 and 2001. Typical symptoms were soft rots characterized by moist and watery decay of the whole cactus stem, which initiated as small water-soaked lesions and enlarged rapidly to the entire stem. The causal organism isolated from the infected stems was identified as Pectobacterium carotovorum subsp. carotovorum (Erwinia carotovora subsp. carotovora) based on its physiological and biochemical characteristics and confirmed by the cellular fatty acid composition and Biolog analyses. Artificial inoculation of the bacterium produced the same soft rot symptoms on the cactus stems, from which the same bacterium was isolated and identified. This is the first report of the P. carotovorum subsp. carotovorum in the graft-cactus C. silvestrii in Korea.

• Research in Plant Disease
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• v.14 no.2
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• pp.131-133
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• 2008

From 2006 to 2007, the stem rot of Elsholtzia splendens Nakai caused by Sclerotium rolfsii occurred sporadically in an herbs exhibition at Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The typical symptom is water-soaking, dark 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 stems 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 and sclerotia on PDA was $30^{\circ}C$ and the hyphal width was $4{\sim}9{\mu}$. 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 on the stem rot of E. splendens caused 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.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.

• Research in Plant Disease
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• v.13 no.1
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• pp.50-52
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• 2007

From 2004 to 2005, the stem rot of Disporum sessile D. $D_{ON}$ caused by Sclerotium rolfsii occurred spoyadieally in an herbs exhibition farm of Hamyang, Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The typical symptom is water-soaking, dark brown on the stem and rotting, wilting. The infected plants were mostly died. White mycelial mats were spread over lesions, and then sclerotia were formed on stems and near soil line. The sclerotia were globoid in shape, 1$\sim$3 mm in size and white to brown in color, The optimum temperature and sclerotia on PDA was 30$^{\circ}C$ and the hyphal width was $3{\sim}10{\mu]m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. Pathogenicity of the causal organism was proved on D. sessile according to Koch's postulate. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the stem rot of D. sessile 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.

• 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.

• 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 Plant Pathology Journal
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• v.35 no.6
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• pp.553-563
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• 2019

Investigations related with factors influencing root and crown rot are rare and mainly related to farming practice and soil management. The main objective of this study was to examine broader range of factors influencing stem-base infestation of winter wheat in the field conditions. The effect of spatial distribution of infected plants on disease index (DIs) assessments was also investigated. Analysis of factors influencing DIs of crown rot of wheat demonstrated significant influence of the growing seasons (P < 0.001) and extreme fluctuations in winter temperatures (P < 0.001). In addition to that, localities together with their interaction with the growing season also significantly influenced DIs (P < 0.001). Aggregation of infected plants influenced variability of DI estimations, and it was pointed out that more extensive investigation should be conducted on broad range of DI in order to establish sampling method giving uniform sampling precision. Fusarium graminearum was shown to be predominant Fusarium species in Serbia (72.6%) using sequence-characterized amplified region analysis. Interestingly F. oxysporum was isolated in higher frequencies (27.4%) than it was reported in the literature. Given that there were no reports on the diversity of Fusarium species causing crown rot of wheat in Serbia, this study presents first report on this important subject. It also indicated that more attention should be focused on combined effects of abiotic and biotic factors influencing stem-base infestation of winter wheat. This knowledge will contribute to better understanding of factors influencing root and crown rot of wheat which would ensure sustainable disease management in the future.

• Korean Journal of Microbiology
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• v.1 no.1
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• pp.45-47
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• 1963

1. A Kind of Bacillus, which was seemed to be pathogenic, was isolated from Pinus rigida planting. 2. The bacillus were grown well on the Agar-Bacto-Beef media (pH 7.4) at $30^{\circ}C$. C for 24 hours. 3. The soil infection for the one year old seedling was the best inoculating method in this experiment. 4. Almost of all characteristics were simillar between isolated and reisolated bacillus. 5. The author should like to call temporarily the name of this bacterial disease Stem-rot of pinus rigida Mill.