• 한국균학회지
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• 제38권2호
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• pp.205-207
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• 2010

경남 함양군 경상남도농업기술원 약초 전시포장에서 Sclerotium rolfsii에 의한 쥐오줌풀 흰비단병 증상이 발생 되었다. 주요 병징은 줄기와 잎자루가 수침상으로 물러지고 썩으면서 시들어 말라 죽고, 병반부와 지제부의 토양 표면에 흰색의 곰팡이가 솜털모양으로 자라는 것으로 나타났다. 쥐오줌풀에서 발생한 병징과 병원균의 균학적 특징 및 병원성을 검정한 결과, 이 병을 S. rolfsii 에 의한 쥐오줌풀 흰비단병으로 명명하고자 제안한다.

• The Plant Pathology Journal
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• 제17권2호
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• pp.110-113
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• 2001

Post-harvest diseases of kiwifruit caused severe damages on the fruits during storage, transportation, marketing and consumption. Phomopsis sp. was reported to be one of the major causal organisms of post-harvest fruit rots of kiwifruit. Symptoms of stem-end rot caused by Phomopsis sp. appeared at the stem-end area of the fruit as it ripened. The brown pubescent skin at the area became soft and lighter in color than the adjacent firm healthy tissues. A watery exudate and white mycelial mats were frequently visible at the stem-end area forming a water-drop stain down the sides on the dry brown healthy skin. When the skin was peeled back, the affected flesh tissue was usually watersoaked, disorganized, soft and lighter green than the healthy tissue. Phomopsis sp. was consistently isolated from the diseased fruits, and its pathogenicity was confirmed by an artificial inoculation test on healthy fruit of kiwifruits. The mycological characteristics of the telemorph state of the fungus produced on potato-dextrose agar were in accordance with those of Diaporthe actinidiae. This is the first report on the occurrence of a telemorph state of D. actinidiae as the causal organism of stem-end rot of kiwifruit in Korea.

• 식물병연구
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• 제19권3호
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• pp.229-232
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• 2013

경상남도농업기술원 시험포장에서 S. rolfsii에 의한 오이 흰비단병 증상이 발생하였다. 전형적인 병징으로 시들음, 썩음, 줄기와 과실 수침상을 보였고 감염된 식물체는 결국 시들어 말라 죽었다. 병반부와 토양 표면에 흰색의 곰팡이가 발생하며 갈색의 작고 둥근 균핵이 형성되었다. 감자한천배지에서 균총은 흰색이고 잘 자라며 배양기간이 경과됨에 따라 갈색의 작은 둥근 균핵을 많이 형성하였다. 균핵의 크기는 1-3 mm이며 균사의 폭은 4-8 ${\mu}m$였다. 균사생육과 균핵 형성 적온은 $30^{\circ}C$이었다. 주사전자현미경 검경결과 균사 특유의 clamp connection이 관찰되었다. 코흐의 가설을 만족하기 위해, 50일간 키운 오이 유묘를 이용하여 병원성 검정을 실시한 결과 흰비단병 특유의 병징을 유도하였다. 오이에서 발생한 병징과 병원균의 균학적 특징, 그리고 ITS rDNA 염기서열 비교분석 결과, 이 병을 Sclerotium rolfsii Saccardo에 의한 오이 흰비단병으로 명명하고자 제안한다.

• 한국식물병리학회지
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• 제14권4호
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• pp.325-330
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• 1998

On the basis of the fact that the pycnidiospore of Botryosphaeria dothidea, the causal fungus of apple white rot is a typical water borne spore, a method for quantitative analysis of pycnidiospore dispersal from the warts produced on the diseased apple tree stem was developed. The warts on which cracks developed either on or around them were cut off at the base, and shaked in the water for 4hours at 2$0^{\circ}C$, in which condition the maximum number of spores were released. The volume of shaking solution was calculated as 1 ml per one wart. At the end of shaking, Trio, a household detergent was added to the shaking solution to the concentration of 0.1%, and shaked for additional 10 minutes at 35$^{\circ}C$ to take off the spores attached on the glass ware. One milliliter of the spore suspension thus prepared were passed through transparent membrane filter (pore size : 3.0 ${\mu}{\textrm}{m}$), and the spores attached on the filter were counted under a microscope ($\times$200) after staining them with lactophenol supplemented with aniline blue. The results thus obtained were statistically consistent when at least 30 warts were used simultaneously in single shaking. This method can be applicable in the elucidation of ecology of sporulation and spore dispersal, and also in the screening of the sporulation inhibitor which can be used in the control of the disease by reducing the inoculum density.

• 식물병연구
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• 제19권2호
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• pp.118-120
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• 2013

2007년부터 2009년까지 전북 익산지역의 고구마 육묘장에서 봄에 Sclerotium rolfsii에 의한 고구마 흰비단병이 발생하였다. 초기증상은 황화되어 시들고 감염된 조직 주변과 지제부에 흰색의 균사체가 형성되었다. 육묘시기에는 병에 매우 약하여 감염되면 고사된다. 병원균은 배지 위에서 흰색균사가 빠르게 자라고 7일 후 균핵을 형성하였다. 균핵은 처음에 흰색에서 시간이 경과됨에 따라 갈색으로 변하였다. 따라서 고구마에서 발생한 병징, 병원균의 균학적 특징과 병원성을 검정한 결과, 이 병을 S. rolfsii Saccardo에 의한 고구마 흰비단병으로 동정하였다.

• 미생물학회지
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• 제33권4호
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• pp.252-256
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• 1997

담자균류 백색부후균의 일종인 흰구름버섯(Coriolus hirsutus)을 실험균주로 하여 수종의 난분해성 방향족염료의 분해능을 측정하였다. 사용된 4종류의 염료 중, triphenyl methane 염료인 bromophenol blue가 탈색율 95% 이상으로 가장 잘 탈색되었으며, Congo red와 Poly R-478은 이보다는 낮은 57%, 55%가 탈색되었다. 그러나, heterocyclic 염료인 methylene blue는 본 균주에 의해 거의 탈색되지 않았으며, UV-visible spectrum상에서의 심색성 이동만 관찰되었다. 세포외 laccase와 peroxidase의 활성은 각 염료의 탈색율과 비례하여 나타났으며, 최대 활성 또한 최대 탈색시기에 관찰되었다. 효소의 활성 염색시 모든 염료의 탈색배지에서 공통적인 laccase와 peroxidase의 활성 띠가 관찰되었다. 이러한 결과로 볼 때, 세포외 laccase와 peroxidase가 난분해성 염료의 탈색에 중요한 역할을 할 것으로 판단된다.

• 식물병연구
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• 제9권1호
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• pp.42-46
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• 2003

흰날개무늬병원균의 분생자과를 형성시키기 위하여 NUV 광을 조사하면서 무균적으로 배양하였다. 흰날개무늬병원균을 Oatmeal Agar 배지상에 7일동안 배양시킨 후 살균처리된 배나무 가지를 을려놓아 2$0^{\circ}C$실온에서 5일 동안 NUV 광을 조사하면서 배양하였다. 그 결과, 배나무 가지표면에 분생자병속이 처리 5주후에 95% 형성시킬 수 있었다. 또한, 유기된 분생자병속으로부터 63%의 분생자가 형성되는 것을 관찰하였다. 새롭게 형성된 분생자병속과 분생자의 형태적 특성은 Dematophora necatrix에 대하여 보고된 것과 동일하였다.

• 식물병연구
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• 제27권3호
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• pp.91-98
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• 2021

The current social demand for organic, sustainable, and eco-friendly approaches for farming, while ensuring the health and productivity of crops is increasing rapidly. Biocontrol agents are applied to crops to ensure biological control of plant pathogens. Research on the biological control of white root rot disease caused by a soil-borne pathogen, Rosellinia necatrix, is limited in pears compared to that in apple and avocado. This pathogenic fungus has an extensive host range, and symptoms of this disease include rotting of roots, yellowing and falling of leaves, wilting, and finally tree death. The severity of the disease caused by R. necatrix, makes it the most harmful fungal pathogen infecting the economical fruit tree species, such as pears, and is one of the main limiting factors in pear farming, with devastating effects on plant health and yield. In addition to agronomic and cultural practices, growers use chemical treatments to control the disease. However, rising public concern about environmental pollution and harmful effects of chemicals in humans and animals has facilitated the search for novel and environmentally friendly disease control methods. This review will briefly summarize the current status of biocontrol agents, ecofriendly methods, and possible approaches to control disease in pear orchards.

• Journal of Microbiology and Biotechnology
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• 제29권9호
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• pp.1424-1433
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• 2019

DDT is a hydrophobic organic pollutant, which can be bio-accumulated in nature and have adverse consequences on the physical condition of humans and animals. This study investigated the relationship between the white-rot fungus Pleurotus eryngii and biosurfactant-producing bacterium Ralstonia pickettii associated with the degradation of DDT. The effects of R. pickettii on fungal development were examined using in vitro confrontation assay on a potato dextrose agar (PDA) medium. R. pickettii culture was added to the P. eryngii culture at 1, 3, 5, 7, and 10 ml ($1ml{\approx}1.44{\times}10^{13}CFU$). After 7 d incubation, about 43% of the initial DDT ($12.5{\mu}M$) was degraded by the P. eryngii culture only. The augmentation of 7 ml of R. pickettii culture revealed a more highly optimized synergism with DDT degradation being approximately 78% and the ratio of optimization 1.06. According to the confrontational assay, R. pickettii promoted the growth of P. eryngii towards the bacterial colony, with no direct contact between the bacterial cells and mycelium (0.71 cm/day). DDD (1,1-dichloro-2,2-bis(4-chlorophenyl) ethane), DDE (1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene), and DDMU (1-chloro-2,2-bis(4-chlorophenyl) ethylene) were identified as metabolic products, indicating that the R. pickettii could enhance the DDT biodegradation by P. eryngii.

• The Plant Pathology Journal
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• 제15권4호
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• pp.223-227
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• 1999

Pre-penetration behavior of Boytryosphaeria dothidea on apple fruits was investigated with scanning electron microscopy. Once conidia were deposited on the fruit surface, they germainted and produced germ tubes from one or both ends of the conidia. Germ tubes grew over the fruit surface and entered the fruits through lenticels or surface cracks formed naturally. Germ tubes of the fungus also appeared to penetrated the fruits directly with or without forming appressoria. Globose appressoria were frequently formed at the tip of germ tubes on the fruit surface, where no lenticels or surface cracks were found. The conidia collapsed and became flattened to the fruit surface after appressorial formation. Cuticles of fruit surface underneath appressoria and tips of some germ tubes were evidently altered, indicating possibility of direct penetration of the fungus by enzymatic degradation of the cuticle layers. This the first report on the formation of appressoria by B. dothidea.