• 한국균학회지
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• 제33권2호
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• pp.98-102
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• 2005

2003년부터 2005년 사이에 한국의 두릅나무에 심각한 역병이 발생하였다. 감염된 두릅나무와 토양으로부터 병원균이 분리되었으며, 이 균은 배양적인 그리고 형태적인 특징 및 병원성 검증 실험에 의해 P. cactorum(Lebert&Cohn) J. Schrt.으로 동정되었다. 이 균은 뚜렷한 돌출형이고, 둥근 난형모양의 탈락성 유주포자낭의 특정으로 다른 역병균으로부터 형태적으로 구분되었다. 최적의 생장 온도는 V8 배지와 Oat meal 배지에서의 $25^{\circ}C$이었다. PCR을 통해 ITS rDNA 영역의 약 900 bp의 길이가 증폭되었으며, 세 가지 효소인 Alu I, Msp I, Taq I을 이용한 PCR-RFLP 분석 결과를 PhytID 의 데이터베이스에서 분석한 결과 형태적인 그리고 배양적인 특징에 의한 결과와 일치했다.

• 한국응용곤충학회지
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• 제21권2호
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• pp.68-72
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• 1982

인삼 재배포장에서 병원균인 Fusarium spp.의 밀도와 근부에 영향을 미치는 토양환경요인을 조사하였다. 2년근 포장의 토양을 토성별로 분류하여 결주율, Fusarium spp. 밀도, 화학적 성질을 비교해 본 결과 점토 함량이 들었고 결주율과 질산태 질소는 줄어드는 경향이었으며 다른 성질은 뚜렷한 차이가 없었다. 6년근 포장에서는 근부율과 유효인산 함량이 정의 상관(r=0.3162, p=0.05)을 보였으며 Fusarium spp. 밀도와 Streptomyces spp. 밀도는 고도의 부의 상관(r=-0.3976, p=0.01)을 나타내었다.

• Journal of Ginseng Research
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• 제27권4호
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• pp.195-201
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• 2003

인삼 뿌리썩음병균 Cylindrocarpon destructans의 후막포자형태에 대해서 광학현미경 및 전자현미경을 사용하여 조사하였다. 전형적인 C. destructans의 후막포자는 균사로부터 형성되었으나 분생포자에서는 생성되지 않았다. 그러나 pH 4로 조절된 Czapek Dox broth에서 2$0^{\circ}C$, 12일간 배양하였을 때는 소형분생포자가 미성숙한 후막포자 유사세포로 변형되었다. 후막포자는 potato dextrose agar 및 V-8 Juice agar 그리고 질소원이 결제된 Czapek Dox broth배지에서 2$0^{\circ}C$, 16∼20일 배양으로 생성되었고, 생성된 후막포자는 황갈색 혹은 적갈색을 띄었으며 균사의 중간이나 말단 부위에서 한 개 혹은 사슬형태로 존재하였다. 후막포자는 직경이 11.3∼11.9 $\mu\textrm{m}$이었으며 외부에 1.5∼1.8 $\mu\textrm{m}$ 길이의 혹 같은 돌기가 여러 개 형성되어 표면이 울퉁불퉁 하였다.

• Mycobiology
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• 제43권3호
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• pp.288-296
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• 2015

Thailand is one of the largest citrus producers in Southeast Asia. Pathogenic infection by Phytophthora, however, has become one of major impediments to production. This study identified a pathogenic oomycete isolated from rotted roots of pomelo (Citrus maxima) in Thailand as Phytophthora nicotianae by the internal transcribed spacer ribosomal DNA sequence analysis. Then, we examined the in vitro and in vivo effects of Chaetomium globosum, Chaetomium lucknowense, Chaetomium cupreum and their crude extracts as biological control agents in controlling this P. nicotianae strain. Represent as antagonists in biculture test, the tested Chaetomium species inhibited mycelial growth by 50~56% and parasitized the hyphae, resulting in degradation of P. nicotianae mycelia after 30 days. The crude extracts of these Chaetomium species exhibited antifungal activities against mycelial growth of P. nicotianae, with effective doses of $2.6{\sim}101.4{\mu}g/mL$. Under greenhouse conditions, application of spores and methanol extracts of these Chaetomium species to pomelo seedlings inoculated with P. nicotianae reduced root rot by 66~71% and increased plant weight by 72~85% compared to that in the control. The method of application of antagonistic spores to control the disease was simple and economical, and it may thus be applicable for large-scale, highly effective biological control of this pathogen.

• Journal of Ginseng Research
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• 제44권1호
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• pp.161-167
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• 2020

Background: The ascomycete fungi Cylindrocarpon destructans (Cd) and Fusarium solani (Fs) cause ginseng root rot and significantly reduce the quality and yield of ginseng. Cd produces the secondary metabolite radicicol, which targets the molecular chaperone Hsp90. Fs is resistant to radicicol, whereas other fungal genera associated with ginseng disease are sensitive to it. Radicicol resistance mechanisms have not yet been elucidated. Methods: Transcriptome analyses of Fs and Cd mycelia treated with or without radicicol were conducted using RNA-seq. All of the differentially expressed genes (DEGs) were functionally annotated using the Fusarium graminearum transcript database. In addition, deletions of two transporter genes identified by RNA-seq were created to confirm their contributions to radicicol resistance. Results: Treatment with radicicol resulted in upregulation of chitin synthase and cell wall integrity genes in Fs and upregulation of nicotinamide adenine dinucleotide dehydrogenase and sugar transporter genes in Cd. Genes encoding an ATP-binding cassette transporter, an aflatoxin efflux pump, ammonium permease 1 (mep1), and nitrilase were differentially expressed in both Fs and Cd. Among these four genes, only the ABC transporter was upregulated in both Fs and Cd. The aflatoxin efflux pump and mep1 were upregulated in Cd, but downregulated in Fs, whereas nitrilase was downregulated in both Fs and Cd. Conclusion: The transcriptome analyses suggested radicicol resistance pathways, and deletions of the transporter genes indicated that they contribute to radicicol resistance.

• 식물병연구
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• 제14권1호
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• pp.64-67
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• 2008

2005년부터 2007년까지 경기도 고양시와 용인시의 스파티필럼 재배농가에서 주로 여름철 고온기(6월${\sim}$9월)에 스파티필럼의 지제부위와 뿌리 부분이 썩는 증상이 발생하였다. 이러한 병든 식물체의 병반으로부터 병원균을 분리하여 형태적 배양적 특징을 조사한 결과, 분생포자는 긴 막대모양의 양끝이 둥글고, 1-3개의 격막이 있으며 크기는 $67.5-95.0{\times}4.8-6.5\;{\mu}m$(평균 $82.0{\times}6.0\;{\mu}m$)였다. 병원균의 최적생육 온도는 $27^{\circ}C$였으며 병원성 시험결과 접종 5일만에 첫 병징이 조사되었다. 본 병원균은 병징과 균학적 특징을 조사한 결과, Cylindrocladium spathiphylli로 동정하였으며 스파티필럼 뿌리썩음병으로 명명하여 국내에 처음 보고한다.

• 한국균학회지
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• 제40권1호
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• pp.44-48
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• 2012

인삼의 뿌리썩음병 방제를 위하여 다양한 식물 근권 토양으로부터 유용방선균을 분리하였으며 이들의 생물활성을 조사하였다. 93종의 분리 방선균 중 콜로니가 상이하고 항균활성이 우수한 방선균 8종을 선발하였다. 이들 방선균(A75, A501, A515, A523, A704, A03-1444, A3265, A3283)은 siderophore를 생산하며 cellulase와 protease와 같은 곰팡이 세포벽 분해효소를 생산하였다. 또한 인삼뿌리썩음의 주요 원인균인 C. destructans, B. cinerea, R. solani 등에 대하여 강한 길항 활성을 나타내었다.

• 한국약용작물학회지
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• 제14권2호
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• pp.107-112
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• 2006

Two Atractylodes species, A. japonica Koidz. ex Kitam. (AJ) and A. macrocephala Koidz (AM) were used in this study. AJ population had higher amounts of Sesquiterpenoids and stronger tolerance to root rot but less vigor of root growth than AM population. Two populations (AJ and AM) were crossed to make interspecific hybrid population. A total of 98 lines propagated clonally were selected from a cross of AJ and AM, and evaluated for contents of sesquiterpenoids, atractylon (ATLN) and atractylenolide III (AT3) using high performance liquid chromatography (HPLC), and growth characters such as plant height, stem number and root weight. HPLC profiles of the hybrids were compared with those of parent plants, and it demonstrated the production of introgression hybrid by crossing between AJ and AM. Of 98 clonal lines,10 lines were selected by 10% level based on the growth vigor and tolerance to root rot, and AJM2102-51 line showed the heaviest root weight (117.1 g/plant) among them. A total of 98 hybrid lines contained on average $0.16\;{\pm}\;0.10\;mg/g$ of $AT3,\;2.00\;{\pm}\;1.37\;mg/g$ of ATLN, and $2.16\;{\pm}\;1.40\;mg/g$ of total sesquiterpenoids, showing high coefficients of variation (above 65%). Ten lines having high contents of sesquiterpenoids were selected, and AJM2101-15 had the highest amount (9.83 mg/g) of ATLN, and showed 40.8 g/plant of root weight similar to mean value (39.9 g/plant) of hybrid lines. The result showed that the introgression of both characters of vigorous growth from AM and high sesquiterpenoids content from AJ could be possible to make new hybrid lines by crossing between AJ and AM.

• Journal of Microbiology and Biotechnology
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• 제33권10호
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• pp.1299-1308
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• 2023

Carya cathayensis is an important economic nut tree that is endemic to eastern China. As such, outbreaks of root rot disease in C. cathayensis result in reduced yields and serious economic losses. Moreover, while soil bacterial communities play a crucial role in plant health and are associated with plant disease outbreaks, their diversity and composition in C. cathayensis are not clearly understood. In this study, Proteobacteria, Acidobacteria, and Actinobacteria were found to be the most dominant bacterial communities (accounting for approximately 80.32% of the total) in the root tissue, rhizosphere soil, and bulk soil of healthy C. cathayensis specimens. Further analysis revealed the abundance of genera belonging to Proteobacteria, namely, Acidibacter, Bradyrhizobium, Paraburkholderia, Sphaerotilus, and Steroidobacter, was higher in the root tissues of healthy C. cathayensis specimens than in those of diseased and dead trees. In addition, the abundance of four genera belonging to Actinobacteria, namely, Actinoallomurus, Actinomadura, Actinocrinis, and Gaiella, was significantly higher in the root tissues of healthy C. cathayensis specimens than in those of diseased and dead trees. Altogether, these results suggest that disruption in the balance of these bacterial communities may be associated with the development of root rot in C. cathayensis, and further, our study provides theoretical guidance for the isolation and control of pathogens and diseases related to this important tree species.

• 식물병연구
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• 제7권1호
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• pp.8-10
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• 2001

1998년 경기도 고양시의 분화용 칼랑코에(Kalanchoe sp.)재배농가에서 줄기 하부가 검게 썩으며 급격히 시드는 증상으로부터 병원균을 분리.동정한 결과 Phytophthora nicotianae로 동정되었다. 병원균의 형태적 특성은 뚜렷한 유두돌기를 가진 유주자낭을 형성하였고, 원형~rPfis형이며 크기는 20~48$\times$24~64$\mu\textrm{m}$였고, 구형의 후막포자를 다량 형성하였다. 배양적 특성은 V8 juice agar와 corn-meal agar에서는 풍부한 균사를 형성하였으며, PDA에서는 전형적인 거미집 형태로 자라는 특성을 보였다. 생육온도범위는 최저 1$0^{\circ}C$, 최고 37$^{\circ}C$, 최적온도는 3$0^{\circ}C$였다. \\\"Florus\\\"를 비롯한 14개 칼랑코에 주요 재배품종에 대한 병원성검정을 실시한 결과 품종에 따라 저항성의 차이가 있었다.의 차이가 있었다.