• 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.

• Research in Plant Disease
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• v.18 no.1
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• pp.54-56
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• 2012

Sclerotium rot of sponge gourd occurred at the experimental field of Gyeongsangnam-do Agricultural Research and Extension Services in August 2010. The infected fruits showed water-soaked and rot symptoms. White mycelial mats spread over lesions, and then sclerotia were formed on fruit and near 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 PDA was $30^{\circ}C$ and the hyphal width was 4-8 ${\mu}m$. 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 to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report of sclerotium rot on sponge gourd caused by S. rolfsii in Korea.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.90-92
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• 2008

In 2007, a bulb rot of Allium victorialis var. platyphyllum Makino caused by Sclerotium rolfsii occurred sporadically in a herb farm at Gyeongsangnam-do, Korea. The symptom initiated with water-soaking lesion and progressed into bulb rot and wilt of a whole plant. Severely infected plants were blighted and killed eventually. White mycelial mats appeared on the lesion at early stage and a number of sclerotia were formed on the bulb. The sclerotia were spherical, $1{\sim}3 mm$ and white to brown. The optimum temperature for the growth and sclerotia formation was $30^{\circ}C$ on PDA. The hyphal width was measured $4-9{\mu}m$. The typical clamp connections were observed on PDA. Based on the symptom, mycological characteristics and pathogenicity to the host plant, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the bulb rot of A. victorialis var. platyphyllum caused by S. rolfsii in Korea.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.205-207
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• 2010

Stem and petiole rot symptoms of Valeriana fauriei occurred sporadically in the herb exhibition field in Gyeongsangnam-do Agricultural Research and Extension Services, Hamyang-gun, Gyeongnam Province in Korea. The typical symptom is water-soaking on the stem, rotting, wilting, blighting and the infected plants eventually died. White mycelial mats spreaded over lesions, and then sclerotia were formed on the infected plant parts and near soil surface line. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii. This is the first report of stem rot on Valeriana fauriei caused by Sclerotium rolfsii in Korea.

• The Plant Pathology Journal
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• v.17 no.2
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• pp.110-113
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• 2001

Post-harvest diseases of kiwifruit caused severe damages on the fruits during storage, transportation, marketing and consumption. Phomopsis sp. was reported to be one of the major causal organisms of post-harvest fruit rots of kiwifruit. Symptoms of stem-end rot caused by Phomopsis sp. appeared at the stem-end area of the fruit as it ripened. The brown pubescent skin at the area became soft and lighter in color than the adjacent firm healthy tissues. A watery exudate and white mycelial mats were frequently visible at the stem-end area forming a water-drop stain down the sides on the dry brown healthy skin. When the skin was peeled back, the affected flesh tissue was usually watersoaked, disorganized, soft and lighter green than the healthy tissue. Phomopsis sp. was consistently isolated from the diseased fruits, and its pathogenicity was confirmed by an artificial inoculation test on healthy fruit of kiwifruits. The mycological characteristics of the telemorph state of the fungus produced on potato-dextrose agar were in accordance with those of Diaporthe actinidiae. This is the first report on the occurrence of a telemorph state of D. actinidiae as the causal organism of stem-end rot of kiwifruit in Korea.

• Journal of Ginseng Research
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• v.24 no.2
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• pp.53-57
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• 2000

Chlamydospores were isolated from hyphae of Cylindrocanon destmctans by homogenization and/or ultrasonic treatment. Rate of the isolated chlamydospores by the homogenization with glass tissue grinder were 9.8% of all total chlamydospores formed in the culture of C. destructans. The length of mycelial fragments after the homogenization was about 400㎛ They were, however, formed in clusters of the chlamydospores and the mycelia The rate of the isolated chlamydospores from additional ultrasonic treatment after the homogenization of the mycelia were 74.3%. The length of mycelial fragments with the ultrasonic treatment was about 20 fm and chlamydospores seemed to be isolated from the mycelial mats and dispersed evenly in the culture. The numbers of chlamydospore in a catena were 1 to 8 cells after the homogenization on potato dextrose agar (PDA). Meanwhile the numbers of them after added ultrasonic treatment were 1 to 4 cells. Germination percentages of the isolated chlamydospores from the ultrasonic treatment were 46.8% after incubation of 2 days on PDA at 20。C and 60.7% after incubation of 13 days at 5。C, respectively. Germination rate of chlamydospores to the total chlamydospores produced by the ultrasonic treatment was 55.8%. However, it was increased to 74% when it was measured in the germinated catenae to the total catenae.

• The Korean Journal of Mycology
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• v.45 no.3
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• pp.246-250
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• 2017

Sclerotium rot was observed on mungbean (Phaseolus radiatus L.) plants cultivated in the exhibition field of Gyeongsangnam-do Agricultural Research and Extension Services in September 2015. The progression of rot was initially observed as water-soaked lesions on several parts of the affected plant. Severely infected plants were blighted and eventually died. White mycelial mats spread over the lesions and numerous sclerotia formed on stems 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 $30^{\circ}C$ and the hyphal width was $4{\sim}8{\mu}m$. Typical clamp connections were observed on the hyphae of fungus grown on PDA. For molecular identification, the complete internal transcribed spacer (ITS) ribosomal DNA (rDNA) of the causal fungus was sequenced and analyzed. Based on the mycological characteristics, ITS rDNA sequence analysis, and pathogenicity to host plants, the fungus was identified as Sclerotium rolfsii. This is the first report of Sclerotium rot on mungbean caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.19 no.3
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• pp.229-232
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• 2013

Sclerotium rot of cucumber (Cucumis sativus L.) occurred at the experimental field of Gyeongsangnam-do Agricultural Research and Extension Services in July 2012. The typical symptoms included wilt, rot, and water-soaking on stems and fruits and severely infected plants eventually died. White mycelial mats spread over lesions, and then sclerotia were formed on fruit and near soil line. The sclerotia were globoid in shape, white to brown in color and 1-3 mm in size and the hyphal width was 4-8 ${\mu}m$. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. For further identification, the complete internal transcribed spacer (ITS) rDNA region was amplified and sequenced. On the basis of mycological characteristics, ITS rDNA region comparison, and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report of sclerotium rot on cucumber 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.

• 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.