• Mycobiology
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• 제30권2호
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• pp.65-69
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• 2002

Sclerotial development of Grifola umbellata(Pers. : Fr.) Donk was investigated through microscopic examinations. The sclerotium of G. umbellata was bumpy and rugged, multi-branched, and dark-brown to black in color. The sclerotial development of G. umbellata was categorized into three stages such as sclerotial initial, development and maturation. Sclerotium development was initiated as the white fungal mass. The superficial part of white sclerotium changed into gray, light brown and then black as its development proceeded further. As a distinctive characteristic of this fungus, a large number of crystals were observed in the medulla layer of sclerotium during its maturation. For development of new sclerotium, G. umbellata formed a white sclerotial primordium on the matured sclerotium. Development of sclerotium in G. umbellata was intimately associated with rhizomorphs of Armillariella mellea and the developing sclerotia were often penetrated by rhizomorphs of A. mellea into medulla layer.

• The Plant Pathology Journal
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• 제34권5호
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• pp.367-380
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• 2018

Stems and pods of hyacinth bean cultivated in a farmer's field in Gazipur District, Bangladesh, were found rotted in nearly 5% hyacinth bean plants. A fungus having fluffy mycelium and large sclerotia was isolated from affected tissues. Combined results of morphological, molecular and pathological analyses identified the fungus as Sclerotinia sclerotiorum (Lib) de Bary. Inoculating the fungus on healthy hyacinth bean plants and pods reproduced the symptoms previously observed in the field. The three isolates obtained from naturally infected plants were cross inoculated in hyacinth bean, okra and African-American marigold and they were pathogenic to these hosts. The optimum temperature and pH for its growth were $20^{\circ}C$ and pH 5.0, respectively. Sclerotial development was favored at pH 5.0. Sucrose and mannitol were the best carbon sources to support hyphal growth, while glucose was the most favourable for sclerotial development. The hyacinth bean genotypes, HB-82 (Rupban Sheem) and HB-102 were found highly resistant, while HB-94 (Ashina) was moderate resistant to the fungus. Finally, S. sclerotiorum was sensitive to Bavistin, Dithane M-45 and Rovral fungicides and Ca in the form of $CaCl_2$. This observation could possibly aid in eliminating field loss in hyacinth bean caused by an emerging pathogenic fungus S. sclerotiorum.

• Mycobiology
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• 제35권2호
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• pp.87-90
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• 2007

A total of 520 overwintered sclerotia were collected from surface of soil under mulberry trees in six locations in Korea during February in 2006 and 2007. The collected sclerotia were tested for their germination in vitro and identified based on their morphological characteristics. Out of all sclerotia tested, 52.3% of the sclerotia germinated and produced two types of apothecia. The two types of fungi occurred from the sclerotia at the ratio of 49.8 vs. 50.2. The fungal type with cup-shaped apothecia was identified as Ciboria shiraiana and another type of fungus with club-shaped apothecia as Scleromitrula shiraiana. Taxonomy and distribution of the two sclerotial fungi were described and discussed.

• 한국버섯학회지
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• 제11권4호
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• pp.194-200
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• 2013

Polyporus umbellatus (Syn. Grifola umbellata) is a sclerotium forming mushroom belongs to family Polyporaceae of Polyphorales, Basidiomycota. The sclerotia of P. umbellatus have long been used for traditional medicines in China, Korea and Japan. This study was initiated to obtain the basic data for artificial sclerotial production of P. umbellatus. Here, we investigated the favorable conditions for mycelial growth of P. umbellatus and its symbiotic fungus Armillaria mellea. We also evaluate the favorable carbon and nitrogen sources for sclerotial formation in dual culture between P. umbellatus and A. mellea. The favorable conditions for mycelial growth of P. umbellatus were $20^{\circ}C$ and pH 4, while optimal conditions for mycelial growth of A. mellea were $25^{\circ}C$ and pH 6. The carbon sources for optimal mycelial growth of P. umbellatus were fructose and glucose, while carbon sources for favorable mycelial growth of A. mellea were also fructose and glucose. The nitrogen sources for favorable mycelial growth P. umbellatus were peptone and yeast extract, while optimal mycelial growth of A. mellea were obtained in peptone and yeast extract. When P. umbellatus and A. mellea were dual cultured on carbon sources, sclerotia were induced on basal media supplemented with glucose, fructose and maltose at pH 4~6, while nitrogen sources inducing sclerotia were basal media supplemented with peptone and yeast extract for 60 days at $20^{\circ}C$ under dark condition.

• 한국균학회지
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• 제39권2호
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• pp.131-135
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• 2011

2종의 상추균핵병균(S. sclerotiorum, S. minor)에 기생성인 선발진균(CM2)의 형태적 및 분자적 특성을 조사한 결과, Paraconiothyrium minitans로 동정되었다. P. minitans CM2의 균사 배양조건은 pH 6.5로 조절한 PDA배지를 사용하고, $22^{\circ}C$에서 1일 12시간 주기의 근자외선광을 처리하여 배양하는 것이 가장 좋은 것으로 나타났다. P. minitans CM2의 분생포자현탁액을 상추균핵병균의 균핵에 처리하여 발아에 미치는 영향을 조사한 결과, 균핵의 직접발아와 자낭반 형성이 전혀 이루어지지 않았다.

• 식물병연구
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• 제11권2호
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• pp.128-134
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• 2005

파속채소에 발생하여 큰 피해를 주는 흑색썩음균핵병균을 대상으로 외국 도입균주와 국내 분리균주간의 유전형을 UP-PCR을 이용하여 Tyson 등이 보고한 방법으로 조사한 결과, 국내에서 분리되는 Sclerotium cepivorum은 UP-PCR그룹 b에 속하는 것으로 확인되었으며, 대균핵 형성균과 DNA profile에 있어서 현저한 차이를 보였다. 두 가지 병원균의 균핵 표면구조를 전자현미경을 이용하여 확인한 결과, S. cepivorum은 대균핵 형성균에 비해 잔주름이 적고 내부에 포자와 유사한 구조가 관찰되었다. 흑색썩음균핵병을 일으키는두 가지 병원균은모두 $10\~25^{\circ}C$에 범위에서 생장되었고 생장 최적온도는 $20^{\circ}C$이었으며, $28^{\circ}C$ 이상에서는 전혀 자라지 않았다. 두 가지 병원균의 균핵 형성정도는 $20^{\circ}C$에서 배양시 가장 높았고 균핵 발아정도는 $20\~24^{\circ}C$ 범위에서 높았다 처리온도를 달리하여 처리일수별로 휴면중인 병원균 균핵의 발아정도를 조사한 결과, $35^{\circ}C$에서 7일간 전처리한 후 $10^{\circ}C$에서 7일간 배양했을 때 발아가 가장 잘 되었으며 S. cepivorum은 $70\%$,대균핵 형성균은 $100\%$발아되었다. 담수기간 및 처리온도가 병원균의 생존에 미치는 영향을 조사한 결과 처리온도가 높아질수록 균핵 발아 정도가 감소되는 것으로 나타났다. 흑색썩음균핵병을 일으키는 두 가지 병원균은 토양습도에 따라 발병정도에 있어서 큰 차이를 보였다. 마늘흑색썩음균핵병은 토양습도가 $15\%$(-300 mb)일 때 가장 높은 발병을 보였으며 $17\%$ 이상되거나 $13\%$ 이하로 되었을 때에는 토양습도가 $15\%$일 때에 비해 병 발생이 현저히 감소되었다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.120.1-120
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• 2003

White rot on Allium species recently had a high incidence as increased cultivating areas of tropical garlic types in Korea. Two types of Sclerotium have been known as causal agents producing different size and shapes of sclerotia in infested fields. We developed a new method for isolation of two types 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 0.5mm and 0.25mm sieve 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 direct count of sclerotia under dissecting microscopy.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1987년도 식물생명공학 심포지움 논문집 Proceedings of Symposia on Plant Biotechnology
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• pp.157-167
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• 1987

The have been many reports that phenoloxidase are correlated with development in many fungi. C. congregatus, one of nushroom-forming basidiomycetes, which requires light for its development also has phenoloxidases. In C. congragatus, there are two sets of membrane-associated phenoloxidase (PHO I and PHO II) which are differentiated by their isozyme patterns, and each enzyme set consists of two different subtrate specific enzyme protein; o-tolidine reacting enzyme, and DOPA reacting enzyme. PHO I which is localized by a protoplast-concanavalin A technique by using a new solidifying agent, Pluronic Polyol F 127, instead of agar appears in the vegetative hyphae, and PHO II appears at the early primordial stage on agar and at the sclerotial stage of liquid shake cultures. Inhibition of PHO I with the enzyme inhibitors inhibits mushroom formation as well as melanization of the vegetative hyphae at concentrations which do not inhibit the vegetative growth. PHO I deficient mutants do not form mushrooms or melanins, and the mutants show abnormal nuclear migration patterns. PHO II has roles; possibly cementing the adjacent hyphae during the actual three dimensonal structure formation, and melanizing mushrooms and sclerotia. The possible roles of PHO I in the light reception complex and in melanin formation, the function of malanin, and possible roles of postulated post translational modifying enzymes which regulate the phenoloxidases, nuclear migration pattern, and self-nonself recognition mechanism are discussed.

• 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.

• 한국균학회지
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• 제41권4호
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• pp.292-294
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• 2013

2010년 2월에 경기도 용인시 남사면의 소엽풍란 재배농가에서 소엽풍란의 잎과 줄기가 갈색으로 변하면서 말라죽는 피해증상이 발생하였다. 이병 식물체 표면에는 잿빛을 띤 곰팡이가 형성되어 있었으며, 주변 환경이 습할수록 병반 상에 분생포자가 더 많이 만들어지는 경향을 보였다. 균학적 특징으로 분생포자는 난형 및 타원형이고, 무색이며, 단세포로서 크기는 $5.3-16.5{\times}3.8-11.0{\mu}m$이었으며, 갈색의 분생포자경과 검정색 균핵을 형성하였다. 이러한 형태적 특성을 근거로 하여 소엽풍란의 병원균을 Botrytis cinerea로 동정하였으며, 병원성을 검정한 결과 잿빛곰팡이병의 발생을 확인할 수 있었다. 이와 같이 소엽풍란에서 발생한 병을 Botrytis cinerea에 의한 잿빛곰팡이병으로 확인하였고, 본 병을 소엽풍란 잿빛곰팡이병으로 명명하며 우리나라에서 처음으로 보고한다.