• Research in Plant Disease
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• v.9 no.3
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• pp.145-148
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• 2003

In April of 2002, the gray mold disease occurred severely on kalanchoe (Kalanch oe blossfeldiana) grown in a nursery in Daesan-myon, Changwon City, Korea. The lesions were started with water-soaked spot and the leaves discolored from the tip and became gray or dark and gradully expanded to whole leaf. The conidia and mycelia of pathogen appearedd on flower, flower stalk and stem. Conidia were gray, 1-celled, mostly ellipsoid or ovoid in shape and were 8~17 ${\times}$5~12${\mu}m$ in size. Conidiophores were 13~34${\mu}m$ in size. The sclerotia were formed abundantly on potato-dextrose agar. The optimum temperature for sclerotial formation was $20^{\circ}C$. Pathogenicity of the causal organism was proved on Kalanchoe blossfeldiana according to Koch,s postulate. The causal organism was identified as Botrytis cinerea based on mycological characteristics. This is the first report on gray mold of Kalanchoe(Kalanchoe blossfeldiana) caused by Botrytis cinerea in Korea.

• Research in Plant Disease
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• v.10 no.4
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• pp.337-340
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• 2004

In April of 2003, the gray mold disease caused by Botrytis cinerea was occured in zinnia seedlings grown in greenhouse at Gyeongsangnam-do Agricultural Research and Extension Services, and farmer's nursery. The symptoms of infected plants were started with water-soaking lesions in flower bud, leaves and stems. The lesions gradually expanded and infected plants became withered and discolored to gray or dark from the tip. The conidia and mycelia of the pathogen were appeared on flowers, leaves and stem. The conidia were gray, 1-celled, mostly ellipsoid or ovoid in shape and were 5${\sim}$16 ${\times}$ 4${\sim}$8 ${\mu}m$ in size. Conidiophores were 12${\sim}$28 ${\mu}m$ in size. The pathogenic fungi formed sclerotia abundantly on potato dextrose agar. The optimum temperature for sclerotial formation was $20^{\circ}C$. Pathogenicity of the causal organism was proved according to Koch's postulate. The causal organism was identified as Botrytis cinerea Persoon: Fries based on mycological characteristics. This is the first report on gray mold of Zinnia elegans caused by Botrytis cinerea in Korea.

• The Plant Pathology Journal
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• v.22 no.1
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• pp.7-10
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• 2006

Anthracnose severely occurred on begonia (Begonia semperflorens Link.) nurseries in Gyeongju, Gyeongbuk in July, 2004. More than $80\%$ of begonia seedlings were diseased in the greenhouse surveyed and diseased leaves per plant were $12.1\%$ in average. Yellowish spots occurred on the leaves of begonia as initial symptoms, and they coalesced irregularly to form large brown pleomorphic lesions. Severely infected leaves were defoliated, resulting in abnormal growth of the entire plant. Colletotrichum sp. was repeatedly isolated from the diseased plants and was identified as Colletotrichum acutatum on the basis of the mycological characteristics on potato dextrose agar and RAPD analysis. Pathogenicity of the fungus was also confirmed by artificial inoculation on healthy plants. The optimum temperature for mycelial growth of C. acutatum was around $25^{\circ}C$. The fungus was sensitive to azoxystrobin, bitertanol, diethofencarb-carbendazim, difenoconazole and tebuconazole. This is the first report on the anthracnose of begonia caused by C. acutatum 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.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.26 no.3
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• pp.190-193
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• 2020

In 2014, Anthracnose symptoms were observed on fruit of pumpkin in Gangneung, Gangwon in Korea. The typical symptoms on fruit surfaces were circular lesions, brown, shriveled with salmon-colored spore masses on the spots. A fungal isolate was obtained from symptomatic on fruit and cultured on potato dextrose agar at 25℃. The color of the upper surface of the colony varied from white to gray with occurrence of salmon-colored conidial masses and was red to violet on the underside. The causal fungus of anthracnose isolated from the diseased fruits was identified as Colletotrichum fioriniae based on mycological characteristics and sequences of the internal transcribed spacer, glyceraldehyde-3-phosphate dehydrogenase, chitin synthase-1 gene, histone H3, actin gene, beta-tubulin gene region. Pathogenicity tests of the isolate were performed on pumpkin fruit by both wound and non-wound inoculation with conidial suspension (1×10⁶ conidia/ml) and incubated at 25℃. Lesions were observed on both wounded and non-wounded fruit of pumpkin after 7 days inoculation in only C. fioriniae. The pathogen was re-isolated from the lesions of inoculated fruits. To our knowledge, this is the first report of anthracnose on fruit of pumpkin caused by C. fioriniae in Korea.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.72-74
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• 2001

A destructive collar rot of water cress (Oenanthe javanicav) occurred in the commerical farm at Karye-myon, Uiryong-gun, Kyongsangnam-do in 2000. The causal fungus caused stem rot, crown rot, wilt or blight of water cress and the disease incidence in 3 fields ranged from 28.6 to 42.8%. White mycelia spread over tissues near the soil surface or stems, and sclerotia developed on the lesions at late season. The fungus grew well on PDA at $20^{\circ}C$ and the typical clamp connection was formed on its tough white mycelia $4.1{\sim}10.3{\mu}m$. The fungus also formed white mycelia mats and sclerotia at $20^{\circ}C$ on PDA. The sclerotia were globoid and sized $1.0{\sim}6.3{\times}1.0{\sim}5.2mm$ (av. $2.4{\sim}2.2mm$). The causal fungus of collar rot disease was identified as Sclerotium rolfsii on the basis of mycological characteristics and pathogenicity test, This is the first report on the collar rot of water cress caused by Sclerotium rolfsii in Korea.

• The Korean Journal of Mycology
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• v.32 no.1
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• pp.50-53
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• 2004

In March of 2003, the gray mold occurred severely on pea (Pisum sativum) grown in the green houses and open fields in Changseon-myon, Namhae-gun, Gyeongnam Province, Korea. The symptoms started with water-soaking lesions in the leaves, stems and pods. The typical symptoms of the leaves, stems and pods became withered, discolored and blighted, and then eventually died. The mycelia, conidia and conidiophore of the pathogen appeared on leaves, stems and pods. The conidia were gray, 1-celled, mostly ellipsoid or ovoid in the shape and were $8{\sim}17{\times}5{\sim}13\;{\mu}m$ in size. Conidiophores were $14{\sim}30\;{\mu}m$ in size. The sclerotia were formed abundantly on potato dextrose agar. The optimum temperature for sclerotial formation was $20^{\circ}C$. Pathogenicity of the causal organism was proven according to Koch's postulate. The causal organism was identified as Botrytis cinerea based on mycological characteristics. This is the first report on gray mold of Pisum sativum caused by B. cinerea in Korea.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.130-133
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• 2004

Leaf blight and fruit rot of sweet persimmon (cv. Fuyu) caused by Pestalotia diospyri were observed during the growing season and postharvest such as storage and transport, respectively. Typical symptoms on leaves developed with small brown spots and were later reddish brown colors. In the storage fruit, the white mycelial mats formed between fruit and calyx. The pathogenic fungus was isolated from infected fruits and cultured on potato dextrose agar (PDA). Colony color of the fungus was white at first on PDA. Conidia were ovoid or fusiform, 5 cells, middle 3 cells were olive, upper and lower 2 cells were colorless, and their size were $16{\sim}22\;{\times}\;6{\sim}8\;{\mu}m$. They had were $2{\sim}3$ appendage at basal cell and size $9{\sim}18\;{\mu}m$. Based on the cultural and mycological characteristics and pathogenicity test on host plants and fruits, the fungus was identified as Pestalotia diospyri Syd.&P. Syd. This is the first report on the leaf blight and fruit rot of sweet persimmon caused by Pestalotia diospyri in Korea.

• Research in Plant Disease
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• v.21 no.4
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• pp.334-336
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• 2015

Sclerotium rot on Pulsatilla koreana was observed in the exhibition field of Jinju Agriculture Technology Center in July 2013. The infected plants showed water-soaked, blighted and rotted symptoms. White mycelial mats spread over lesions, and then numerous sclerotia were formed on flower stalk and flower 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 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. For molecular identification, the complete ITS rDNA sequence of the causal fungus was sequenced and analyzed. 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 Pulsatilla koreana caused by S. rolfsii in Korea.