• Mycobiology
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• v.33 no.1
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• pp.1-6
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• 2005

Morphological characteristics of hyphal interaction between Grifola umbellata (Pers. Ex Fr.) Pilat and its companion fungus which related to sclerotia formation from hyphae were investigated by external observations, light microscopy and transmission electron microscopy (TEM). External observations showed that a dense antagonism line was formed by both G. umbellata and companion fungus after their hyphae contacted each other in dual culture. Many hyphal strands emerged on the colony of G. umbellata and differentiated to sclerotia from where hyphal strands crossed. Light microscope observations revealed the process of antagonism line formation. Mature antagonism with structural differentiation, was composed of three main layers: the rind, the rind underlayer and the hypha layer. TEM observations showed that after colonies hyphal contact, a series of reactions always occurred in both G. umbellata and companion fungus. Cells in the center of antagonism line were dead. Cells of G. umbellata adjacent to the antagonism line were usually large and hollow, with unilateral thickened wall, whereas those of companion fungus were empty, with thin or thick wall. Both hyphal interaction at the antagonism line may be one of the main reasons for sclerotia of G. umbellata differentiation from hypha.

• Research in Plant Disease
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• v.16 no.3
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• pp.323-325
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• 2010

The stem rot of sunflower (Helianthus annuus) occurred sporadically in the experimental field of Gyeongsangnam-do Agricultural Research and Extension Services, on September, 2009. The infected plants were wilted and water-soaked brown spots were formed on the stem, than infected stems 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, 1~3 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 $4{\sim}8\;{\mu}m$. The typical clamp connections were observed in the hyphae of the pathogenic fungus. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii. This is the first report on the stem rot of sunflower by S. rolfsii in Korea.

• Research in Plant Disease
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• v.19 no.4
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• pp.308-312
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• 2013

The popcorn disease caused by sclerotia forming fungi reduces the productivity of mulberry fruits in world wide. In Korea, only two species (Ciboria shiraiana and Scleromitrula shiraiana) have been reported as the major causal organisms and their morphological features are also largely unknown. Hereby, we report the first identification of another species (i.e. Ciboria carunculoides) in Korea and detailed features of their anamorphic stage. Fungi dominantly associated with sclerotia were purely isolated from infected mulberry fruits under the microscope. PCR-amplified DNA encoding 5.8S rRNA displayed 100% similarity to Ciboria carunculoides. The anamorphic features exhibited the absence of true mycelia. Instead, very short, aseptated, branched conidiophores were directly emerged from sclerotia. Phialides were usually three in number from each conidiophore, ampuliform to navicular in shape, slightly curved and tapering towards the apex. Conidia were produced from phialides and mostly found as one celled, pear shaped, not hyaline with smooth to uneven surface walled. Diversely modified features in phialides formed pseudo-mycelial structures around the host tissue. Combined all, current study is the first report of C. carunculoides isolated in Korea and the foremost detailed description of its anamorph stage.

• 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.

• Mycobiology
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• v.29 no.1
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• pp.58-60
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• 2001

A destructive stem rot of wild aster(Aster koraiensis) occurred sporadically some farmers' fields in Guman-myon, Kosonggun, Kyongsangnam-do in 2000. One of the most severely infected field in Kosong showed 28.6 percent of infection rate. The fungus also caused stem or crown rot and systemic wilt or blight of the plants. White mycelium spread over stems and petioles of infected plants and sclerotia formed on the old lesions and near the soil surface. The fungus showed maximum mycelial growth around $30^{\circ}C$ and did not grow under $5^{\circ}C$ and over $45^{\circ}C$ and mycelial width were $4.3{\sim}10.2{\mu}m$. Colony was white, usually many narrow mycelial stand in the aerial mycelium and formed clamp connection. Numerous sclerotia were formed on PDA at $30^{\circ}C$. The shape sclerotia were globoid and $0.8{\sim}3.0{\times}0.9{\sim}3.4$ mm in size. The fungus was isolated repeatedly from the infected tissues and confirmed its pathogenecity to wild aster and identified as Sclerotium rolfsii. This is the first report on the stem rot of wild aster caused by S. 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.

• Mycobiology
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• v.30 no.2
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• pp.102-104
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• 2002

In July 2001, a destructive stem rot of tatarian aster(Aster taturicus) was occurred sporadically in exhibition farm of Gyeongsangnam-do Agricultural Research and Extension Services, in Hamyang, Korea. The fungus also caused collar and crown rot and systemic wilt or blight of whole plant. White mycelium spread over stems and petioles of infected plants and sclerotia formed on the old lesions and near the soil surface. The fungus showed maximum mycelial growth was obtained around $30^{\circ}C$ but did not grow below $5^{\circ}C$ or above $45^{\circ}C$. The mycelial width ranges $4.2{\sim}10.4{\mu}m$. and the color is white, usually many narrow mycelial stand grow in the aerial mycelium and formed clamp connection. Numerous sclerotia were formed in artificial media like PDA at $30^{\circ}C$. The shape of sclerotia were sphere and $1.0{\sim}3.2{\mu}m$ in diameter. The fungus was isolated repeatedly from the infected, tissues and confirmed its pathogenecity to aster and identified as Sclerotium rolfsii. This is the first report that Sclerotium rolfsii causes stem rot of tatarian aster in Korea.

• Korean Journal of Plant Resources
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• v.11 no.3
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• pp.296-300
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• 1998

When medicinal mushroom, Poria cocos, is cultured , inoculation method of spawn is cross slice inoculation of which the both sides of pine tree were peeled and spawn of P.cocos was inoculated. However, this method required lots of inoculation amount. This study was carried out to improve the culturing method of P. cocos. A good growth of P.cocos was observed in MCM(mushroom complete medium), showing proper mycelia growth and density. In inoculation amount, conventional method(cross slice inoculation) requires 20 bottles of spawn. In contrast, short log method required 8 bottles of spawn and drilling inoculation method 2~3 bottles, which could save by 60% and 85-90% respectively. In the selectrion of tree species, pine and larch had better condition for spawn culture and sclerotia formation condition.In terms of yield , pine was 33.7kg/3.3$m^2$. In the yield of pine, conventional method was 23.4kg/3.3$m^2$, drilling inoculation 29.4kg/3.3$m^2$, short log inoculation 31.7kg/3.3$m^2$, therefore drilling inoculation could increase by 25% and short log inoculation 35%, In addition, management cost was also saved.

• The Korean Journal of Mycology
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• v.27 no.6 s.93
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• pp.378-382
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• 1999

This study was carried out to improve an artificial culture techniques and antioxidative activity of the crude extract isolated from sclerotia of Poria cocos(Fr.) Wolf. In the test of different spawns and inoculation method, the sclerotia formation, number of sclerotia and production yield were excellent in the both sides inoculation method of log spawn, whereas the both side inoculation method of sawdust spawn was poor in sclerotia formation and yield. The optimal spawn and inoculation method for the quality and productivity of P. cocos was in the order of log spawn (both sides inoculation > log spawn(cutting section inoculation) > sclerotia (both sides inoculation) > sawdust spawn (both sides inoculation). The physiological activity substance, crude extract content of P. cocos NIAST 13007 was about 83%. As the concentration of crude extracts increased, the relative viscosity tended to be increased. However, as the concentration of sodium chloride increased, the relative viscosity did not affected. In antioxidative activities, electron donating ability (EDA) of P. cocos was about 10% of butylated hydroxytoluene (BHT). Thiobarbituric acid (TBA) value was similar to that of the vitamin C, however the peroxide value (POV) was lower than those of BHT and vitamin C.

• Mycobiology
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• v.32 no.2
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• pp.95-97
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• 2004

In July 2002, a destructive stem rot of tawny daylily(Hemerocallis fulva) was occurred sporadically in exhibition farm of Gyeongsangnam-do Agricultural Research and Extension Services located in Hamyang-gun, Korea. The fungus also caused collar and crown rot, and systemic wilt or blight of whole plant. White mycelium spread over stems and petioles of infected plants and sclerotia were formed on the old lesions and near the soil surface. The optimum temperature for mycelial growth and scierotial formations was $30^{\circ}C$ on PDA. The mycelial width ranged $4.2{\sim}10.4{\mu}m$ and the color was white, usually many narrow mycelial strand grew in the aerial mycelium and formed clamp connection. The shape of sclerotia was spherical and $1.0{\sim}3.2$ mm in diameter. The fungus was isolated repeatedly from the infected tissues and confirmed its pathogenicity to Hemerocallis fulva and identified as Sclerotium rolfsii. This is the first report on the stem rot of H. fulva caused by S. rolfsii in Korea.