• The Plant Pathology Journal
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• 제20권4호
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• pp.240-243
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• 2004

White rot on Allium crops recently had a high incidence with incrensed cultivating areas of tropical garlic types in Korea. Two types of Sclerotium have known as causal agents that produce different size and shapes of sclerotia in infested fields. Therefore, we developed a new method for isolation of sclerotia from infested field soils that can be used for ecological study of Sclerotium spp. and establishment of control strategy. Soil samples collected from heavily infested fields were evenly mixed and placed on a automatic sieve shaker connected with tap water, After 10 min of shaking, residues on 0.5 mm and 0.25 mm sieves were separately collected and suspended with 70% sugar solution, which method floats sclerotia in aqueous layer, Then, floated fraction was carefully separated and mixed with a same volume of 1% sodium hypochlorite solution to differentiate with organic materials. This method provides a direct count of sclerotia under a dissecting microscopy.

• Research in Plant Disease
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• 제21권1호
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• pp.36-39
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• 2015

In June 2012 and 2013, a destructive stem rot symptoms of Ligularia fischeri occurred sporadically in Hoengseong-gun and Pyeongchang-gun Gangwon-do, Korea. The typical symptom included water-soaking on the main stem, rotting, wilting and blighting, which eventually leads to death of the plant. White mycelial mats were spread over lesions and brown sclerotia were formed on stems and near soil surface. The sclerotia were white to brown, spherical or irregular, 1-3 mm in size on potato dextrose agar (PDA), The optimum temperature range of hyphal growth was $25-30^{\circ}C$ and the hyphal diameter was $4-10{\mu}m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. The resulting sequence of 695 bp was deposited in GenBank. A BLAST search revealed that sequences of the this isolates showed >99% identity with those of Sclerotium rolfsii. On the basis of the morphological characteristics and phylogenetic analyses of molecular markers ITS rDNA, the fungi were identified as S. rolfsii. A pathogenicity test was carried out to fulfill Koch's postulates. To our knowledge, this is the first report of S. rolfsii on Ligularia fischeri in Korea.

• Journal of agriculture & life science
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• 제50권4호
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• pp.27-34
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• 2016

Sclerotium rolfsii is a well known broad host range soil borne plant pathogenic fungus and caused serious damage to various vegetable crops. To develop an effective biological control agent for S. rolfsii, an isolate which showed strong inhibitory effect on the mycelial growth of S. rolfsii was selected among the antagonistic bacterial isolates collected from vinyl-house soil. The bacterial isolate was identified as Bacillus amyloliquefaciens KBC1009 based on the morphological, physiological characteristics and by 16S rRNA sequence analysis. The growth conditions for B. amyloliquefaciens KBC1009 were optimized in LB media(pH7) by culturing at 30℃ for 72 hrs. Glucose and yeast extract were confirmed as the best carbon and nitrogen sources, respectively. In order to test the inhibitory effect of B. amyloliquefaciens KBC1009 to stem rot of pepper, green house experiment was conducted. Drench of 1/500 diluted bacterial suspension of B. amyloliquefaciens KBC1009(5×108 cfu/ml) to each pepper plant 3 times with 10 days interval showed 66.7% control effectiveness. These results suggest that B. amyloliquefaciens KBC1009 is one of promising biocontrol agent to control stem rot caused by Sclerotium rolfsii.

• The Plant Pathology Journal
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• 제15권4호
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• pp.236-241
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• 1999

Sclerotinia twig blight on trees and cottony rot on fruits of Satsuma mandarin were observed in Cheju, Korea in 1996 and 1997. The causal fungus causing citrus twig blight and cottony rot was identified as Sclerotinia sclerotiorum which had cup-shaped apothecia bearing hyaline and clavate asci and periphyses on sclerotium. Symptoms were produced on twigs, developing young leaves, fully developed new leaves, and fruits 2-9 days after wound inoculation, but only on twigs with young lateral buds and developing young leaves by unwound inoculation. The fungus grew well between 10 and $27^{\circ}$, but optimum temperature was $24^{\circ}$ on potato dextrose agar. Most varieties were highly susceptible to S. sclerotiorum, whereas some varieties such as Ichinan were relatively resistant among twelve Satsuma mandarin varieties in the field. This is the first record of Scledrotinia twig blight on trees and cottony rot on stored fruits of Satsuma mandarin in Korea.

• Microbiology and Biotechnology Letters
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• 제46권4호
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• pp.395-402
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• 2018

The efficacy of formulated Trichoderma harzianum-based Tricho-compost, seed treatment with Tricho-inocula, and chemical fungicide Provax 200 WP against foot and root rot diseases of wheat caused by Sclerotium rolfsii was tested in the pot house and in the research field of Plant Pathology Division, Bangladesh Agricultural Research Institute, Gazipur, Bangladesh. Tricho-compost was prepared with a mixed substrate of cow dung, rice bran, and poultry refuse colonized by T. harzianum. Seedling mortality of wheat was significantly reduced by the Tricho-compost, Tricho-inocula, and Provax 200 WP both in the pot house as well as in the field experiments. The yield of wheat was sharply increased over the control due to the T. harzianum formulations and Provax 200 WP. Among the treatments, soil application of Tricho-compost was more efficient in reducing seedling mortality and accelerating plant growth with an increased yield of wheat with S. rolfsii-inoculated pot cultures and field experiments.

• The Korean Journal of Mycology
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• 제10권2호
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• pp.93-94
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• 1982

Soybean Whetzelinia rot caused by Whetzelinia sclerotiorum was observed in Jinju area. The diseased soybean plants showed withering and sudden collapse under field conditions. Diseased parts exhibited numerous black, irregularly-shaped scleratia embedded in dense white cottonly mycelium on tissue and in the pith of diseased stems. A sclerotium in the moist sand produced several apothecia under laboratary condition. The primary inoculum was supposed to originate from overwintered sclerotia of soil and soybean debris.

• Mycobiology
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• 제32권3호
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• pp.128-133
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• 2004

Twenty plant extracts were tested against mycelial growth, sclerotium formatiom and dry weight of mycelium with sclerotia of Sclerotium rolfsii Sacc. The highest(90 mm) mycelial growth was measured in Adhatoda vasica, Tegetes erecta, Allium cepa, and Curcuma longa. The lowest(25 mm) was in Azadirachta indica. No mycelial growth was found in any concentration of cow, buffalo, and goat urine. The highest(90 mm) and the lowest(15 mm) mycelial growth were measured in Biomil and Urea, respectively. No mycelial growth was observed in Zinc. The highest(60 mm) and the lowest(2 mm) mycelial growth were recorded in Macuprex(Dodine; 65% WP) and Boron(100% Boric acid and 17% Boron) respectively. Mycelial growth was totally inhibited in Rovral(Iprodione; 50% WP).

• Research in Plant Disease
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• 제29권2호
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• pp.184-187
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• 2023

In May 2020, we surveyed disease occurrence on vegetables grown in Seosan area, Korea. During the disease survey, white rot symptoms were observed in Korean wild chive (Allium monanthum) plants growing in fields. The symptoms occurred mainly in the seed bulb-producing fields of the crop. The above ground parts of the diseased plants displayed premature yellowing and dying of older leaves and stunting of the plants. The bulbs and roots of the diseased plants turned black and rotted. The disease occurred in a range of 1-60% in four of the eight fields surveyed. Three isolates of Sclerotium sp. were obtained from the bulb lesions of diseased plants. All isolates were identified as Stromatinia cepivora based on the morphological characteristics and phylogenetic analysis. Pathogenicity of the isolates on Korean wild chive was confirmed by artificial inoculation test. The lesions induced by the inoculation test were similar to those observed in the investigated fields. This is the first report of S. cepivora causing white rot in Korean wild chive.

• Korean Journal of Pharmacognosy
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• 제3권2호
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• pp.73-79
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• 1972

Losses, literature and occurence of ginseng diseases in Korea were reviewed briefly. Some problems on etiology, epidemiology and control measures of root rot caused by Cylindroaroon panacis, anthracnose, and damping-off have been discussed. Ginseng was added as a new host of $Sclerotium\;rolfsii\;S_{ACC}$.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 한국식물병리학회 1999년도 임시총회 및 추계 학술발표회
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• pp.29.2-29
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• 1999