• 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.

• Journal of Mushroom
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• v.12 no.2
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• pp.117-121
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• 2014

The experiments were conducted to provide information on the chemical concentrations and cultural characteristics in the periods of hyphal incubation, primordial formation, and fruiting bodies yield of winter mushroom, Flammulina velutipes at the mixture ratio of the raw materials. Substrates were analyzed for pH, total carbon (T-C), total nitrogen (T-N), and C/N ratio. In case of Flammulina velutipes, yield of fruiting bodies were 190.5 g/850 ml in the substrates, [Corn-cob + Rice bran + Soybean curd residue (75:20:5)], which was increased 20.4% more than the control, [Douglas fir sawdust + Rice bran (75:25)]. But the periods of hyphal incubation took 28 days, which was 7 days longer than the control. Also, in the substrates [Douglas fir sawdust + Rice bran + Soybean curd residue (75:20:5)], the yields was 172.7 g/850 ml and the periods of hyphal incubation was 21 days.

• The Korean Journal of Mycology
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• v.29 no.2
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• pp.131-133
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• 2001

A destructive collar rot disease was found on broad bean (Vicia faba) in several farmer's field located in Changseon-myon, Namhae-gun, Gyeongsangnam-do in 2001. The typical symptoms of the disease were stem rot, crown rot, wilt or blight. Upper parts of the infected stems were mostly blighted and white mycelial mats were spread over lesions and the sclerotia were formed on the stems near soil line. The infection rates of the disease in the surveyed area were ranged from 28.6 to 42.8%. The sclerotia of the fungus readily formed in artificial media such as PDA at $30^{\circ}C$ and its shape was globoid or irregular and size was $1.0{\sim}3.7{\times}1.0{\sim}2.8\;mm\;(av.\;1.0{\sim}2.3\;mm)$ and was brown or dark brown in color. The optimum temperature for growth of the fungus was about $30^{\circ}C$. The typical clamp connections were found in the hypha of the fungus grown on PDA. On the basis of mycological characteristics and pathogenecity test on host plants, the fungus was identified as Sclerotium rolfsii. This is the first report on the collar rot of broad bean caused by Sclerotium rolfsii in Korea.

• Research in Plant Disease
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• v.9 no.4
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• pp.221-223
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• 2003

In May 2002, a destructive stem rot of Obedient plant (Physostegia virginiana) occurred sporadically in an exhibition farm of Hamyang-gun, Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The typical symptoms of the disease were stem rot, crown rot, wilt or blight. Upper parts of the infected stems were mostly blighted. White mycelial mats were spread over lesions and the sclerotia were formed on the stems near soil line. The sclerotia was globoid or irregular in shape, 1${\sim}$3 mm in size, and brown in color. The optimum temperature for fungal growth was about $30^{\circ}C$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA, and hyphal diameter was 3.6${\sim}$9.4 ${\mu}m$. On the basis of mycological characteristics and test of pathogenecity to host plants, the fungus was identified as Sclerotium rolfsii. This is the first report on the stem rot of Physostegia virginiana caused by Sclerotium 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.

• Research in Plant Disease
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• v.29 no.4
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• pp.420-424
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• 2023

In 2020, within the Dongbaekdongsan area in Jeju Island, a Septobasidium sp. associated with a felt disease in Castanopsis sieboldii (Makino) Hatus. ex T. Yamaz. & Mashiba was identified. The symptom included the presence of brown, thin, and silk-like mycelial mats attached to the tree's bark, displaying variations in size from large to small. To induce hyphal growth, the samples collected were incubated in a moist chamber, and the newly formed hyphae were subjected to genomic DNA extractions. The nucleotide sequences of the internal transcribed spacer and small subunit rDNA genes were determined, and molecular characteristics among the isolates were investigated through polymerase chain reaction-based restriction fragment length polymorphism analysis. This Septobasidium sp. exhibited distinct morphological and phylogenetic features compared to those that were previously reported in South Korea. Consequently, this strain is taxonomically classified as a provisionally novel species of Septobasidium. Furthermore, the observed felt disease exhibited a high degree of host specificity, as it was exclusively identified in C. sieboldii without occurrence in other tree species at the time of observation.

• 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.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 Plant Pathology Journal
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• v.19 no.3
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• pp.181-183
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• 2003

Corky root symptoms caused by Pyrenochaeta lycopersici were observed on the roots and stem base of tomato plants in Korea. Symptoms on infected plants typically appeared as stunting and generally lacking vigor, and infected plants die back from the foliage tips after fruits have set. Brown lesions appearing with bands around the roots were characteristic symptoms of the disease. The lesions become swollen and cracked along the length of the root with corky appearance. Based on cultural and morphological characteristics, the fungus from the diseased plants was identified as Pyrenochaeta lycopersici. Pycnidia were solitary, globose to subglobose, brown to black, darker around the neck region, and measured 173-215 $\mu\textrm{m}$ in diameter with septate setae up to 102-132$\times$6.5 $\mu\textrm{m}$. Conidia were hyaline, unicellular, and 4.2-4.7$\times$l.5-2.0 $\mu\textrm{m}$ long. Optimum temperature for mycelial growth of the p. lycopersici isolates ranged from $20^{\circ}C$ to $25^{\circ}C$. Fifteen isolates off lycopersici were tested for pathogenicity to susceptible and tolerant cultivars of tomato plants by artificial inoculation. Three isolates of P. lycopersici induced typical corky root discoloration on susceptible tomato cultivars but not on tolerant tomato. This is the Erst report in Korea of tomato corky root disease caused by P. lycopersici.