• The Plant Pathology Journal
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• 제19권2호
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• pp.79-84
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• 2003

Sclerotinia rot occurred severely on some vegetable crops grown in Namyangju, Yangpyung, and Yangiu areas in Korea in 2001-2002. The crops infected with Scterotinia sp. were Adenophora remotiflora, Armoracia lapathfolia, Angelica acutiloba, Angelica archangelica, Anthriscus sylvestris, Aster tataricus, Beta vulgaris var. cicla, Brassica campestris var. marinosa, Brassica juncea var. laciniata, Chicholium intybus, Lactuca indica var. dracoglossa, Lactuca sativa var. oak-leaf, Petroselinum crispum, and Phyteuma japonicum. The fungus associated with the disease was identified as Sclerotinia sclerotiorum, based on the morphological characteristics of the pathogen. The symptoms were water-soaked spots that enlarged later and became a watery soft rot. Infected parts became yellow and then turned brown, followed by death of the whole plant. White mycelia developed on the upper petioles and leaves and on the soil where these plant parts lay. Then black sclerotia in variable size and shape formed from the mycelial mass. Pathogenicity of the fungus was proven by artificially inoculating each crop. This is the first report of Sclerotinia rot on the listed vegetable crops in Korea.

• 한국균학회지
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• 제50권1호
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• pp.41-46
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• 2022

Gastrodia elata infected with root rot disease was collected from cultivated G. elata fields in Gimcheon, Korea, in 2018. G. elata tuber surfaces exhibited root rot disease symptoms of dark-grey lesions and white fungal mycelial growth. The fungus was isolated from symptomatic tubers and cultured. Based on morphological characteristics and molecular analysis of the internal transcribed spacer region of ribosomal DNA and translation elongation factor 1-alpha, the isolated fungus was Fusarium oxysporum. This is the first report of root rot caused by F. oxysporum on G. elata tubers in Korea.

• 식물병연구
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• 제19권1호
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• pp.49-54
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• 2013

Sclerotinia white rot disease was observed on 5 and 6-year-old ginseng (Panax ginseng) roots in Hongchun, Cheorwon, and Yanggu, Gangwon Province, Korea from 2006 to 2010. Symptoms included a brownish watery soft rot of the roots, and black sclerotia were often found on the rotten roots. The causal agent of the disease was identified as Sclerotinia nivalis based on cultural characteristics and sequence analyses of the internal transcribed spacer region of rDNA and ${\beta}$-tubulin gene with 100% sequence similarity. Pathogenicity tests were performed on 2-year-old ginseng roots with mycelium plugs without wounds. A watery soft rot of the roots and black sclerotia were observed 10 days after inoculation. These symptoms were identical to those observed on naturally infected roots. The same fungus was re-isolated from the lesions induced by artificial inoculation. This is the first report of sclerotinia white rot caused by S. nivalis on P. ginseng in Korea.

• Journal of Microbiology and Biotechnology
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• 제10권3호
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• pp.344-348
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• 2000

Abstract The removal percentage (94%) of 100 ppm of pyrene in a shaken culture of white rot fungus, Irpex lacteus, was much higher than that in a static culture (37.9%). Over 90% of the pyrene disappeared with I. lacteus grown at $15-27^{\circ}C$, yet less than 50% was removed at $37^{\circ}C$. The transformation rates of pyrene ($4.5-5.0{\;}\mu\textrm{g}/ml/day$) were not very different among cultures with 5- 30% inoculum sizes, and over 90% of the 100 ppm pyrene was removed in every case during 20 days of incubation. The biodegradation of pyrene by I. lacteus was confirmed by measuring the $CO_2$ evolved from the mineralization of the added pyrene. The activity of lignin peroxidase (LiP), which is known to be involved in the biodegradation by white rot fungi, was high between 8 to 12 days of incubation. Although manganese peroxidase activity was demonstrated during the same period as LiP, its activity was quite low, and no laccase activity was detected. Even though the activity patterns of ligninolytic enzymes did not coincide with the pyrene removal, this study shows that I. lacteus has a high biodegrading capability and can be a candidate for the bioremediation of polycyclic aromatic hydrocarbon contaminants.inants.

• 식물병연구
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• 제16권3호
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• pp.323-325
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• 2010

2009년 9월 경상남도농업기술원 해바라기 재배포장에서 흰비단병이 발생되었다. 병징은 줄기 부분이 수침상으로 물러지고 부패되면서 병반부와 토양 표면에 흰색의 곰팡이가 솜털모양으로 생기고 갈색의 작은 둥근 균핵을 많이 형성하였다. 균핵의 크기는 1~3 mm이며 균사의 폭은 $4{\sim}8\;{\mu}m$이었다. 균사생육과 균핵형성의 적정온도는 $30^{\circ}C$이었다. 균사 특유의 clamp connection이 관찰되었다. 해바라기에 발생한 병징과 병원균의 균학적 특징 및 병원성을 검정한 결과, 이 병을 Sclerotium rolfsii에 의한 해바라기 흰비단병으로 명명하고자 제안한다.

• 한국균학회지
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• 제36권2호
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• pp.203-205
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• 2008

2006년에서 2008년까지 진주에서 재배중인 페튜니아에서 병이 발생하였다. 병징은 줄기와 잎이 수침상으로 물러지고 썩으면서 갈색으로 변하며 시들어 말라 죽었다. 줄기, 지제부 및 토양 표면에 솜털모양의 흰색 균사체가 생기고 $1{\sim}3\;mm$ 크기의 둥근 갈색 균핵을 많이 형성하였다. PDA배지 상에서 병원균의 균사 폭은 $4{\sim}8\;{\mu}m$이며 clamp connection이 형성되었고 균사생육과 균핵형성 적온은 $30^{\circ}C$이었다. 페튜니아에서 발생한 병징과 병원균의 균학적 특징 및 병원성을 기초로 본 병을 Sclerotium rolfsii Saccardo에 의한 페튜니아 흰비단병으로 명명하고자 제안한다.

• 한국균학회지
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• 제37권2호
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• pp.198-200
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• 2009

From 2008 to 2009, the stem rot of Astragalus sinicus L. caused by Sclerotium rolfsii occurred sporadically in Gyeongnam area, Korea. The typical symptom is water-soaking, rotting and wilting on the stem. The infected plants were eventually died. White mycelial mats were spread over lesions, and then sclerotia were formed on stems and near soil line. The sclerotia were globoid in shape, white to brown in color, 1-3 mm in size and the hyphal width was 3-9 μm. The optimum temperature for mycelial growth and sclerotial formation on PDA was 30oC. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the stem rot of A. sinicus caused by S. rolfsii in Korea.

• Mycobiology
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• 제38권2호
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• pp.156-158
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• 2010

Stem rot disease was found in garlic (Allium sativum L.) cultivated from 2008 to 2010 in the vegetable gardens of some farmers in Geumsan-myon, Jinju City, Gyeongnam province in Korea. The initial symptoms of the disease were typical water-soaked spots, which progressed to rotting, wilting, blighting, and eventually death. White mycelial mats had spread over the lesions near the soil line, and sclerotia had formed over the mycelial mats on the stem. The sclerotia were globoid in shape, 1~3 mm in size, and tan to brown in color. The optimum temperature for growth and sclerotia formation on potato dextrose agar (PDA) medium was $30^{\circ}C$. The diameter of the hyphae ranged from approximately 4 to $8\;{\mu}m$. Typical clamp connection structures were observed in the hyphae of the fungus, which was grown on PDA medium for 4 days. On the basis of the mycological characteristics and pathogenicity of the fungus on the host plants, the causal agent was identified as Sclerotium rolfsii Saccardo. This is the first report of stem rot disease in garlic caused by S. rolfsii in Korea.

• 한국미생물·생명공학회지
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• 제46권3호
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• pp.300-312
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• 2018

Whole-genome sequencing of the wood-rotting fungus, Flammulina fennae, was carried out to identify carbohydrate-active enzymes (CAZymes). De novo genome assembly (31 kmer) of short reads by next-generation sequencing revealed a total genome length of 32,423,623 base pairs (39% GC). A total of 11,591 gene models in the assembled genome sequence of F. fennae were predicted by ab initio gene prediction using the AUGUSTUS tool. In a genome-wide comparison, 6,715 orthologous groups shared at least one gene with F. fennae and 10,667 (92%) of 11,591 genes for F. fennae proteins had orthologs among the Dikarya. Additionally, F. fennae contained 23 species-specific genes, of which 16 were paralogous. CAZyme identification and annotation revealed 513 CAZymes, including 82 auxiliary activities, 220 glycoside hydrolases, 85 glycosyltransferases, 20 polysaccharide lyases, 57 carbohydrate esterases, and 45 carbohydrate binding-modules in the F. fennae genome. The genome information of F. fennae increases the understanding of this basidiomycete fungus. CAZyme gene information will be useful for detailed studies of lignocellulosic biomass degradation for biotechnological and industrial applications.

• Mycobiology
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• 제46권2호
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• pp.138-146
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• 2018

Two-hundred and fifty-five strains of actinomycetes isolated from soil samples were screened for their antagonistic activities against four well-known wood decay fungi (WDF), including a brown rot fungus, Gloeophyllum trabeum and three white rot fungi Donkioporia expansa, Trametes versicolor, and Schizophyllum commune. A dual culture assay using culture media supplemented with heated or unheated culture filtrates of selected bacterial strains was used for the detection of their antimicrobial activity against four WDF. It was shown that Streptomyces atratus, S. tsukiyonensis, and Streptomyces sp. greatly inhibited the mycelial growth of the WDF tested compared with the control. To evaluate the biocontrol efficacy of S. atratus, S. tsukiyonensis, and Streptomyces sp., wood blocks of Pinus densiflora inoculated with three selected Streptomyces isolates were tested for weight loss, compression strength (perpendicular or parallel to the grain), bending strength, and chemical component changes. Of these three isolates used, Streptomyces sp. exhibited higher inhibitory activity against WDF, especially G. trabeum, as observed in mechanical and chemical change analyses. Scanning electron microscopy showed that cell walls of the wood block treated with Streptomyces strains were thicker and collapsed to a lesser extent than those of the non-treated control. Taken together, our findings indicate that Streptomyces sp. exhibits the potential to be used as a biocontrol agent for wood decay brown rot fungus that causes severe damage to coniferous woods.