• Journal of Microbiology and Biotechnology
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• 제24권1호
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• pp.13-18
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• 2014

Bacillus subtilis JW-1 was isolated from rhizosphere soil as a potential biocontrol agent of bacterial wilt caused by Ralstonia solanacearum. Seed treatment followed by a soil drench application with this strain resulted in >80% reduction in bacterial wilt disease compared with that in the untreated control under greenhouse conditions. The antibacterial compound produced by strain JW-1 was purified by bioactivity-guided fractionation. Based on mass spectroscopy and nuclear magnetic resonance spectral data ($^1H$, $^{13}C$, $^1H-^1H$ correlation spectroscopies, rotating frame nuclear Overhauser effect spectroscopy, and heteronuclear multiple-bond correlation spectroscopy), the structure of this compound was elucidated as a cyclic lipopeptide composed of a heptapeptide (Gln-Leu-Leu-Val-Asp-Leu-Leu) bonded to a ${\beta}$-hydroxy-iso-hexadecanoic acid arranged in a lactone ring system.

• The Plant Pathology Journal
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• 제34권1호
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• pp.78-84
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• 2018

Peroxyacetic acid mixture Perosan, composed of peroxyacetic acid, hydrogen peroxide and acetic acid, was evaluated for eco-friendly management of tomato bacterial wilt by Ralstonia pseudosolanacearum. Perosan drastically suppressed in vitro growth of R. pseudosolanacearum in liquid cultures in dose- and incubation time-dependent manners. Higher perosan doses (0.1 and 1%) caused lowered pH and phytotoxicity to detached leaves of two tomato cultivars Cupirang and Benekia 220 in aqueous solution. Treatment with 0.01% of Perosan delayed wilting symptom significantly in the detached leaves of two cultivars inoculated with R. pseudosolanacearum ($10^7cfu/ml$). Soil drenching of 5% Perosan solution in pots caused severe tissue collapse of tomato seedlings at the four-week-old stage of two tomato cultivars. Treatment with 1% Perosan by soil-drenching significantly reduced bacterial wilt in the tomato seedlings of two cultivars. These findings suggest that Perosan treatment can be applied to suppress bacterial wilt during tomato production.

• 농약과학회지
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• 제5권1호
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• pp.1-11
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• 2001

2000년 기상의 특징은 봄철의 극심한 가뭄과 여름철의 이상고온 및 저온현상, 장마기 두차례의 태풍 및 가을철 집중호우에 의한 침수로 요약된다. 벼는 전년에 비해 잎 이삭도열병이 심하게 발생하였으며, 세균성벼알마름병, 깨씨무늬병이 전국적으로 발생하여 문제시되었다. 고추는 역병과 탄저병이 생육후기에 심하게 발생하여 큰 피해를 가져왔으며 토마토는 일부지역에서 시들음병이, 오이, 수박은 CGMMV, 흰가루병, 급성위조증상, 딸기는 흰가루병이 심하게 발생하였다. 마늘은 파종기의 잦은 강우와 겨울철의 많은 강설로 흑색썩음균핵병이 대발생하였고, 봄감자는 가뭄에 의하여 바이러스병이, 가을감자는 집중호우에 의한 침수로 무름병, 풋마름병이 심하게 발생하였으며 고구마는 여느해와 마찬가지로 덩굴쪼김병의 발생이 심하였다. 사과 배의 병해는 예년에 비해 발생이 경미하였고 맥류의 붉은곰팡이병은 봄철의 가뭄으로 발생이 거의 없었다.

• 식물병연구
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• 제28권1호
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• pp.54-56
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• 2022

2021년 7월, 고창 땅콩 재배포장에서 시들음 증상을 보이는 땅콩 지상부를 발견하였다. 병징은 잎이 갈색으로 시들어 말라 죽은 것처럼 보였으며, 채집한 식물체의 지제부를 잘라 표면소독 후 멸균수에 넣었을 때 ooze 현상을 관찰하였다. 땅콩에서 순수분리된 병원균은 16s rRNA 유전자 염기서열과 phylotype 분류, 유연관계 분석을 통해 분리된 균주가 Ralstonia pseudosolanacearum이라는 것을 확인하였다. 현재까지 국내에 보고된 풋마름병은 고추, 토마토, 감자 등을 기주로 발생한다고 알려져 있다. 본 연구는 국내 처음으로 R. pseudosolanacearum에 의해 발생한 땅콩 풋마름병을 보고하고자 한다.

• 식물병연구
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• 제29권2호
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• pp.188-192
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• 2023

식물병 또는 비생물적 스트레스를 감소시키는 것으로 보고된 세균 4종(HS1, H30-3, KJ40 와 BC42)이 Colletotrichum orbiculare 에 의한 오이 탄저병, Acidovorax citrulli에 의한 과실썩음병, Fusarium oxysporum에 의한 오이 덩굴쪼김병에 대한 병 억제 효과가 있는지 검정하였다. HS1, H30-3, KJ40 와 BC42를 토양에 관주처리 할 경우 유도저항성에 의해 오이 탄저병이 감소하였고, KJ40와 BC42는 A. citrulli의 발병을, BC42는 오이 덩굴쪼김병을 억제하였다. 따라서, KJ40은건조피해저감뿐만아니라유도저항성에의 한 오이 탄저병 억제 및 A. citrulli에 의한 병발생 감소효과를 가지며, BC42는 오이 탄저병, A. citrulli와 F. oxysporum에 병을 모두 억제하는 것으로 보아 넓은 범위의 적용 범위를 갖는 생물적 방제제 자원으로 활용할 수 있을 것이다.

• The Plant Pathology Journal
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• 제35권2호
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• pp.137-148
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• 2019

In search of an effective biological control agent against the tomato pathogen Fusarium oxysporum f. sp. lycopersici, rhizospheric soil samples were collected from eight agro-ecological zones of Bangladesh. Among the bacteria isolated from soil, 24 isolates were randomly selected and evaluated for their antagonistic activity against F. oxysporum f. sp. lycopersici. The two promising antagonistic isolates were identified as Brevundimonas olei and Bacillus methylotrophicus based on morphological, biochemical and molecular characteristics. These two isolates were evaluated for their biocontrol activity and growth promotion of two tomato cultivars (cv. Pusa Rubi and Ratan) for two consecutive years. Treatment of Pusa Rubi and Ratan seeds with B. olei prior to inoculation of pathogen caused 44.99% and 41.91% disease inhibition respectively compared to the untreated but pathogen-inoculated control plants. However, treatment of Pusa Rubi and Ratan seeds with B. methylotrophicus caused 24.99% and 39.20% disease inhibition respectively. Furthermore, both the isolates enhanced the growth of tomato plants. The study revealed that these indigenous bacterial isolates can be used as an effective biocontrol agent against Fusarium wilt of tomato.

• 식물병연구
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• 제8권2호
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• pp.78-83
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• 2002

Tobacco diseases have not been recorded until 1900s in Korea, where tobacco plants were introduced at early 1700s. Practical researches on the disease have been conducted since mid 1960s. Major ten tobacco diseases were mosaic caused by tobacco mosaic virus·potato virus Y·cucumber mosaic virus, bacterial wilt, hollow stalk, wild fire caused by angular leaf spot strain, black shank, brown spot, powdery mildew and fusarium wilt. But their annual occurrences were varied according to changes of tobacco varieties and their cultivating practices. As no useful chemicals, several biological tactics have been developed to control the viral or bacterial diseases that give significant economic damages on sustainable crop yield, but not practicable to field farming condition yet. Transgenic tobacco plants containing foreign disease resistant genes have been developed by current bio-technology, but not released to farmers yet. Though some disease-resistant tobacco varieties have been developed by the conventional breeding technology and currently used by farmers, their disease controlling efficacy have been diminished by occurrence of the new strain or race. Future research on tobacco diseases has been focused on technical development to produce high quality tobacco with less production cost, which leads Korean tobacco industry to keep its competence against foreign industry and decreasing overall market.

• 식물병연구
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• 제14권1호
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• pp.32-36
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• 2008

Ralstonia solanacearum에 의한 풋마름병은 토마토, 감자 등의 작물에 심각한 피해를 주고 있으나, 효과적인 방제법이 없는 실정이다. 일반 병원균의 생물적 방제를 위해 Pseudomonas속의 세균이 가장 일반적으로 이용되고 있는데, 이번 연구에서는 각종 작물의 재배지 토양에서 형광성 세균을 분리하여 Pseudomonas속 특이적 PCR과 항생물질(2,4-diacetylphloroglucinol) 생산 관련 유전자의 유무를 조사하였다. 분리된 150개의 Pseudomonas속 세균 중 항생물질 관련 유전자가 검출된 균은 2균주뿐이였으며, 그중 토마토 근권토양으로 분리된 P. putida P84 세균이 각종 식물 병원 세균에 대해 가장 높은 실내 항균력을 나타내었다. P84 균주의 탄소원별 증식효과는 glucose 첨가시에 가장 좋았으며, arabionse, inositol, melibiose 첨가시에도 우수한 증식효과를 나타내었다. P84세균을 이용한 토마토 풋마름병의 포트실험 결과에서는 60%의 방제효과를 나타내었다.

• 식물병과 농업
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• 제5권1호
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• pp.61-63
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• 1999

Bacterial soft rot was observed on radish grown in Hongcheon, Kanwon-Do, Korea. The soft rot symptoms began as small water-soaked lesions. The water-soaked lesions enlarged rapidly in roots and produced a foul odor. When roots were affected in the field, the shoots also became infected and watery, causing infected plants to wilt, disorganize, and die. The causal organism was isolated from the lesions, and the identified as Erwinia chrysanthemi based on the morphological, physiological and biochemical characteristics. E. chrysanthemi is first described bacterium which causes bacterial soft rot on radish in Korea.

• 한국연초학회지
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• 제14권2호
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• pp.116-125
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• 1992

This experiment was conducted to examine characteristics of agronomic characters and estimate of gene effect for several mutant characters. The genetic populations were derived from cross between 83H-5 and Hicks. There were significant difference for plant height, stlk height, leaf shape and bacterial wilt disease index except leaf number, leaf length, and what is more, F3 variance is more than Bl and B2 generation from cross 83H-5 X Hicks. Gene actions for stalk height and bacterial wilt disease were estimated by 3-parameter, and by 6- parameter model for all characters except above two characters but stalk height and bacterial wilt disease index are not significant in the additive and dominance effects. Dominant$\times$dominant epitasis for plant height, dominant and dominant$\times$dominant epistasis for leaf length, additive and additive$\times$additive and dominant$\times$dominant epistasis for leaf width, and additive and additive$\times$dominant epistasis for days to flower were appeared significant in gene action.