• 한국균학회지
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• 제47권4호
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• pp.417-425
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• 2019

다양한 생물적 스트레스로부터 경제적으로 중요한 식물을 보호하기 위한 친환경 biocontrol agents (BCAs)는 오늘날 농업 및 생태 분야에서 다양하게 사용되고 있다. 다양한 BCAs 중에서, 많은 그람 양성Bacillus 속 아종이 친환경 생물학적 살충제 및 비료로서 성공적으로 산업화되었다. 이 연구에서 우리는 식물병원성 균류의 균사생장에 길항 효과를 보여주는 BCAs 중 하나인 Bacillus thuringiensis C25가 흰날개무늬병을 일으키는Rosellinia necatrix에 대한 길항작용이 있음을 확인하였다. 주사전자현미경을 통해B. thuringiensis C25가R. necatrix의 균사 세포벽을 분해하여 균사생장을 억제하는 것을 확인하였다. B. thuringiensis C25의 전장 유전체에서 5,683 유전자 세트의 서열을 동정하였고, 잠재적으로 곰팡이 세포벽 분해 효소 (CWDE)를 암호화하는 유전자 세트를 선발하였다. R. necatrix에 대한 균사성장 억제효과는B. thuringiensis C25의 균사 세포벽 분해 유전자의 전사 활성과 높은 상관 관계가 있었다. 상세하게는, B. thuringiensis C25에서ChiA, B 및 Glycos_transf_2 유전자를 포함하는 CWDE의 전사체 수준은R. necatrix와의 공동 배양에 의해 향상되었다. 결론적으로, 본 연구에서는 B. thuringiensis C25가 R. necatrix를 제어할 수 있는 생물학적 소재가 될 수 있으며, 식물 병원체에 대한 BCA의 항진균성 메커니즘의 이해를 촉진할 수 있음을 제시하였다.

• 식물병과 농업
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• 제1권1호
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• pp.37-44
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• 1995

This study was carried out to select effective fungicides against white and violet root rot caused by Rosellinia necatrix and Helicobasidium mompa with nine fungicides including thiophanate-methyl from 1993 to 1994. Through laboratory, greenhouse and field trials on inhibitory effect of mycelial growth and disease incidence against the two fungal pathogens, 5 fungicides have been selected finally. Thiopanate-methyl, benomyl, iminoctadine-triacetate and isoprothiolane were proven to have high control effect against R. necatrix. In addition to thiopanate-methyl and benomyl, tolclofos-methyl has been selected for effective control of H. mompa, since it showed prominent control effect in field trial than in laboratory or green house test.

• 식물병연구
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• 제15권1호
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• pp.46-50
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• 2009

Cytochalasin E (CE) is a secondary metabolite secreted by Rosellinia necatrix, caused by white root rot, and has toxicity to apple as a toxin during disease progress. This study was conducted to demonstrate the relationship between the production of CE and its pathogenicity. CE producing isolates and non-producing isolates of R. nectatrix were isolated from the mycerial mat of diseased roots and was detected on that using a TLC and HPLC analysis and in vivo pathogenicity test. CE non-producing isolates were not pathogenic to apple roots and not detected CE by TLC and HPLC analysis. It was shown that the production of CE was related to the pathogenicity of R. nectatrix.

• The Plant Pathology Journal
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• 제33권4호
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• pp.362-369
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• 2017

White root rot disease, caused by the pathogen Rosellinia necatrix, is one of the world's most devastating plant fungal diseases and affects several commercially important species of fruit trees and crops. Recent global outbreaks of R. necatrix and advances in molecular techniques have both increased interest in this pathogen. However, the lack of information regarding the genomic structure and transcriptome of R. necatrix has been a barrier to the progress of functional genomic research and the control of this harmful pathogen. Here, we identified 10,616 novel full-length transcripts from the filamentous hyphal tissue of R. necatrix (KACC 40445 strain) using PacBio single-molecule sequencing technology. After annotation of the unigene sets, we selected 14 cell cycle-related genes, which are likely either positively or negatively involved in hyphal growth by cell cycle control. The expression of the selected genes was further compared between two strains that displayed different growth rates on nutritional media. Furthermore, we predicted pathogen-related effector genes and cell wall-degrading enzymes from the annotated gene sets. These results provide the most comprehensive transcriptomal resources for R. necatrix, and could facilitate functional genomics and further analyses of this important phytopathogen.

• The Plant Pathology Journal
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• 제19권3호
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• pp.152-158
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• 2003

Stromata of the white root rot fungus, Rosellinia necatrix, were produced on diseased roots although they were reported to develop rarely in nature. Forty-two (42) out of 47 samples produced synnemata while 23 developed stromata. Forty-seven (47) isolates obtained from diseased root samples were divided into 24 mycelium compatibility groups (MCGs). Sixteen (16) out of 24 MCGs produced stromata. Single ascospore isolates from 10 stroma samples produced dsRNA-containing isolates from diseased tissue beneath stromata. The frequency of synnema production on axenic culture varied among isolates with different origin. The dsRNA was not transmitted vertically to the ascospore offspring despite the infection of various dsRNA in the parental isolates. The dsRNA was absent in 35 ascospore isolates in two stroma samples that originated from the isolates, in which dsRNA was not eliminated by hyphal tip isolation. Consequently, sexual reproduction in the white root rot fungus was suggested to produce propagules as a new infection source and to have the function to eliminate infectious factors such as mycoviruses.

• 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.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2002년도 총회 및 추계학술발표회
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• pp.93.1-93
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• 2002

• 한국유기농업학회지
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• 제5권1호
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• pp.137-147
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• 1996

For the purpose of acquiring microbial agents that can be utilized to biologically control the major airborne diseases to apple trees, such as canker(Botryosphaeria dothidea), bitter rot(Glomerella cingulata), alternaria leaf spot(Alternaria mali), root rot(rosellinia necatrix), canker(Valsa ceratosperma) and gray mold rot(Botrytis cinerea), the effective microorgaisms were isolated, tested for antagonistic activity to the pathogens causing major diseases to apple trees and identifed. Screening of more than 5,000 species of microorganisms collected in nature for them antagonistic action to the pathogens causing 5 major diseases to apple trees resulted in selection of effective species. Out of the 11 species, one species designated as CAP134 demonstrated outstanding activity. The bacterial strain, CAP134 exerted antagonistic efficiency of 57% on an isolated strain and 40% on a donated strain of Botryosphaeria dothidea., 52% on an isolated strain and 46% on a purchased strain of Alternaria mali, 60% on Valsa ceratosperma 25% on Glomerella cingulata, and 64% Rosellinia necatrix. The CAP134 was identified as a bacterial strain to Bacillus subtilis ATCC 6633 based on morephology, culture conditions, and physio-biochemical characteristics.

• 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.

• The Plant Pathology Journal
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• 제35권2호
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• pp.156-163
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• 2019

Our study investigated the available chlorine content, contact time and difference among strains of each pathogen for sodium hypochlorite (NaOCl) to control chemically against soil-borne fungal pathogens, such as Phytophthora rot by Phytophthora cactorum, violet root rot by Helicobasidium mompa, and white root rot by Rosellinia necatrix, causing die-back symptom on apple trees. As a result, the colony growth of Phytophthora cactorum was inhibited completely by soaking over 5 s in 31.25 ml/l available chlorine content of NaOCl. Those of H. mompa and R. necatrix were inhibited entirely by soaking over 160 s in 62.5 and 125 ml/l available chlorine content in NaOCl, respectively. Also, inhibition effect on available chlorine in NaOCl among strains of each soil-borne pathogen showed no significant difference and was similar to or better than that of fungicides.