• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.251-254
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• 1996

1995년 4월, 국내 백합과 채소작물 4개 재배지역에서 흑백썩음균핵병 발생을 조사하였다. 이 병은 마늘에서 최고 85%까지 가장 심하게 발생하였으며, 파에서는 매우 적게 발생하였다. 쪽파와 양파에서는 흑색썩음균핵병이 국내에서는 처음으로 발견되었으며, 발생율은 각각 최고 10%와 30%에 이르렀다. 이 병의 원인균은 배양적 및 형태적 특성에 E라 Sclerotium cepivorum Berk로 동정되었다. 병원성검정 결과, 이 균은 상기한 4종의 백합과 채소작물에 병원성을 나타냈다.

• 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.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.594-597
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• 1998

The optimal quantity of inoculum was determined to screen resistance of garlic cultivars against Sclerotium cepivorum and 30 cultivars was tested. The growth of the pathogen in detached roots, Disease incidence was increased when the inoculum density was raised form 10 to 100 sclerotia. The optimal inoculum density to differentiate resistance or susceptibility of garlic cultivars was seemed to be 50 sclerotia. The cultivars collected from England, Japan, Nepal and Turkey, and cultivars such as common red, PI1356104 and PI135693 were less than the other cultivars in their disease incidence. The growth of S. cepivorum in detached roots varied from 23 to 33 mm according to garlic cultivars. There was no relationship between the disease incidence and the growth in detached roots. The sclerotial germination was increased significantly when root extract was extract was added. The addition of only distilled water resulted in 13% germination, but the addition of 0.25 g of root extract in 100 ml distilled water resulted in more than 85% germination. There was no difference in the stimulation of sclerotial germination among cultivars which showed different resistance.

• Mycobiology
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• v.33 no.1
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• pp.7-11
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• 2005

Twenty-two isolates of Sclerotium rolfsii causing spotted leaf rot from Varanasi, India were grown on 6% Cyperus rotundus rhizome meal agar (CRMA) medium for the induction of athelial stage (Athelia rolfsii). Only one isolate obtained from Sphaeranthus indicus formed basidial stage on CRMA medium while the other 21 isolates did not. Basidial stage was also produced in S. indicus isolate at different concentrations (5.5, 6.0 and 6.5% w/v) of CRMA medium. Size of basidia, sterigmata and basidiospores of this isolate was measured. Basidia clavate, hyaline and measured $10{\sim}12{\times}4{\sim}5\;{\mu}m$ in size, basidiospores hyaline, unicellular, subglobose to ellipsoid produced on sterigmata and measured $3{\sim}5{\times}2{\sim}4\;{\mu}m$ in size, sterigmata hyaline and measured $4{\sim}5{\times}1.5{\sim}2\;{\mu}m$ in size. The results of the present study revealed wide variation in spotted leaf rot isolates of S. rolfsii. A reddish zone around the colony of S. rolfsii isolate from Vernonia sp. was observed on CRMA medium. HPLC analysis of the zone revealed the presence of gallic and ferulic acid which were also thought to be responsible for reduced mycelial growth of the isolate on CRMA medium.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.131.2-132
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• 2003

White rot on garlic caused by Sclerotium cepivorum firstly occurred at Goheoung, Jeonnam in 1998. Thereafter, the disease rapidly spread throughout the country except Gangwon and became a major limiting factor for the cultivation of various Allium species such as garlic, onion, and welsh onion. The disease that has not been reported on a wild garlic(Allium monanthum) previously occurred severely at Seosan, Choongnam in 2003. Among cultivation areas in the region, 10.7％ were infected by the disease and the ratio of diseased plant reached up to 55.0％ in some heavily infected fields. Two species of Sclerotium were consistently isolated from infected samples and identified as S. cepivorum or another Sclerotium sp. Averaged size of sclerotium of the former was 455.0x562.2 urn, while the later was 374.4${\times}$347.2$\mu\textrm{m}$. Patogenicity to Allium species and mycological characteristics such as sclerotium size, growth temperature, and microconidia of the fungi were similar to those reported on other Allium species previously. Consequently, the wild garlic is a newly reported host of the two pathogenic fungi in Korea.

• Research in Plant Disease
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• v.11 no.1
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• pp.28-34
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• 2005

This study was conducted to investigate the control possibility of garlic white rot causing severe yield losses of Allium species and cultivars using cultural practices such as optimal sowing date and burial depth, and lime application. Inoculum density in infested field soil was investigated at different soil depth, and that on the diseased plant debris was done. Inoculum density and recovery ratio of white rot pathogen of garlic was highly different between two species of Sclerotium cepivorum forming comparatively small sclerotia and Sclerotium sp. forming comparatively large ones. It was confirmed that S. cepivorum formed more sclerotia on bulbs of garlic than S. sp., and sclerotial recovery of S. cepivorum was higher than that of S. sp. Inoculum density of white rot pathogen in the infested field at garlic seeding period ranged from one to thirteen sclerotia per 30 g soil. Inoculum density of white rot pathogen decreased remarkably with increasing soil depth and above 95% of sclerotia were distributed within 5 cm of soil depth. Disease severity of white rot was higher on slightly planted garlics than deeply-planted ones. Garlic seed bulbs infected by white rot pathogens were confirmed to be one of main inoculum sources of white rot in the field and the disease incidences caused by garlic seed transmission showed big differences among garlic varieties. When nine garlic varieties harvested from infested plots were sown in the field, highly susceptible varieties, ‘Wando’, ‘Daeseo’, ‘Namdo’ and ‘Kodang’ showed high disease incidences, whereas other five varieties were not infected at all. It was confirmed that white rot occurred higher on early-sown garlics, before middle October, than on late-sown ones, after late October. Meanwhile, increasing application rate of lime ranged from 100 to 300 g reduced disease severity of white rot.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.25-27
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• 2003

Since 1993, a total of 50 problematic plant diseases unrecorded in Korea were surveyed in Gyeongnam province. Totally 34 new host plants to corresponding pathogens investigated in this study were 5 fruit trees, 9 vegetables, 12 ornamental plants, 3 industrial crops, and 5 medicinal plants. Among the newly recorded fruit tree diseases, fruit rot of pomegranate caused by Coniella granati and Rhizopus soft rot of peach caused by Rhizopus nigricans damaged severely showing 65.5% and 82.4% infection rate. Among the vegetable diseases, corynespora leaf spot of pepper caused by Corynespora cassiicola and the crown gall of pepper caused by Agrobacterium tumefaciens, powdery mildew of tomato caused by Oidiopsis taurica were the most severe revealing 47.6%, 84.7%, and 54.5% infection rate in heavily infected fields, respectively. In ornamental plants, collar rot of lily caused by Sclerotium rolfsii, gray mold of primula caused by Botrytis cinerea, soot leaf blight of dendrobium caused by Pseudocercospora dendrobium, sclerotinia rot of obedient plant caused by Sclerotinia sclerotiorum showed 32.7 to 64.8% disease incidence. On three industrial plants such as sword bean, broad bean, and cowpea, eight diseases were firstly found in this study. Among the diseases occurring on broad bean, rust caused by Uromyces viciae-fabae and red spot caused by Botrytis fabae were the major limiting factor for the cultivation of the plant showing over 64% infection rate in fields. In medicinal plants, anthracnose of safflower caused by Collectotrichum acutatum was considered the most severe disease on the plant and followed by collar rot caused by Sclerotium rolfsii.(중략)

• Research in Plant Disease
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• v.10 no.2
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• pp.105-111
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• 2004

Mycelial growth and days required for sclerotial formation(DRSF) in vitro, and disease incidence of infected plants in the field were investigated to evaluate disease resistance of nine garlic cultivars against two species of Sclerotium causing garlic white rot. There were differences among mycelial growth and sclerotial formation of two white rot pathogens on different garlic cultivars in vitro. Mycelial growth showed the highest level on the clove of 'Daeseo'. Sclerotia of two white rot pathogen were formed the earliest on the clove of 'Kodang' and the latest on the clove of 'Namdo'. In field trial all of nine garlic cultivars were highly susceptible to Sclerotium cepivorum and cold-type garlics were less susceptible than warm-type garlics. Meanwhile garlic cultivars used showed differences among resistant responses to Sclerotium sp., forming large sclerotia. All of warm-type garlics showed highly susceptible response, but three cold-type garlics, 'Seosan', 'Danyang' and 'Yechon' showed moderate resistant response and 'Euisung' showed resistant response. To evaluate cultivar resistance of garlics quantitatively disease progress curve was transformed as linear regression equation. Among the intercept (early disease incidence) and the slope (disease infection rate) obtained from the transformed equation, final disease incidence, and area under disease progress curve(AUDPC), AUDPC was the most effective to evaluate disease resistance of garlics to both of white rot pathogens. There was little correlation between mycelial growth and sclerotial formation on garlic cloves in vitro, and epidemiological parameters (early disease incidence, final disease incidence, disease infection rate, AUDPC) obtained from the field trial. Mycelial growth of S. cepivorum was positively correlated with final disease incidence and disease infection rate obtained from the field trial, meanwhile DRSF was negatively correlated with the epidemiological parameters.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.282-287
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• 2012

Sclerotium cepivorum is a causal agent of white rot disease on different plants including Allium species such as garlic. A mycoparasite, Paraconiothyrium minitans S134 was selected for biological control of sclerotinia rot of garlic caused by S. cepivorum. The experiment was carried out in a garlic field in Taean from October in 2011 to June in 2012. Spore suspension of the mycoparasite was treated twice onto soil surface around garlic plants in sowing in 2011 and late Feb. in 2012, and disease rating was made June in 2012. Incidence of white rot in the twice-application plot of the mycoparasite ($5{\times}10^6$ spores/mL) and in the fluquinconazole (WP)-treated plot was 6.8% and 0.4%, respectively, whereas that of control was 19.5%. As the results, P. minitans S134 could be a prospective biofungicide for biological control of white rot of garlic.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.129.1-129
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• 2003

A destructive stem rot of strawberry (cv. Akihime) occurred sporadically in farmers' fields around Daegok-Myeon, Jinju City, Gyeongnam province in Korea. The infected plants showed stem and crown rot, sometimes whole plant blighted. White mycelia spread over stems of infected clones and sclerotia formed on the old lesions near to soil surface. The fungus formed white colony on PDA and showed maximum mycelial growth and scleotial formation around 30$^{\circ}C$. The fungus usually have many narrow mycelial strands in the aerial mycelium and the width were 4.0∼10.0$\mu\textrm{m}$. The typical clamp connections were formed on the mycelium. The shape of sclerotia was globoid and 1.0∼2.8 mm in size. The fungus was isolated repeatedly from the infected tissues and identified as Sclerotium rolfsii. The fungus was inoculated to strawberry and confirmed its pathogenecity This is the first report on the stem rot of strawberry caused by Scierotium rolfsii in Korea.