• 한국식물병리학회지
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• 제13권1호
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• pp.13-17
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• 1997

A causal agent of bacterial soft rot occurring in soybean sprout cultivation in Korea was isolated and identified, and its incidence in several sprout-soybean cultivars was examined. Infected soybean seeds became light brown and whitish, and could not germinate until 3 days after seeding, accompanying rotting of soybean seeds and sprouts. The causal organism isolated from the rotten seeds and sprouts was identified as Erwinia carotovora subsp. carotovora on the basis of its pathogenicity, morphological and physiological characteristics and the results of the Biolog GN microplate test program. The bacterial soft rot by E. c. subsp. carotovora was firstly described in soybean sprout in Korea, and we name it“the bacterial soft rot of soybean sprout”. The disease occurred more frequently in Nam-hae and Fu-reun sprout-soybean cultivars than in Eun-ha, So-baek, and Ik-san cultivars.

• 한국식물병리학회지
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• 제3권3호
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• pp.236-238
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• 1987

A bacterial disease of elephant foot, Hydrosome rivieri Engl., was newly found in Taejon, Korea in August 1986. The affected plants showed symptoms of soft rot on leaf blades and petioles. Bacterial isolates from affected plants found to be pathogenic to elephant foots by antificial inoculation, producing similar symptoms with those produced naturally. The baterium was also pathogenic to carrot, Chinese cabbage, radish, potato and onion, and developed symptom of soft root on them. On the basis of bacteriological characteristics and pathogenicity, tested bacterium was identified as Erwinia carotovora subsp. carotovora and this disease was proposed to name 'Bacterial soft rot of elephant foot'.

• 한국식물병리학회지
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• 제14권5호
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• pp.555-557
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• 1998

Occurrence of soft rots was observed on wasabi (Wasabia japonica Matsum) grown in Chuncheon and Pyengchang Kangwon province, Korea. The symptoms appeared on the wasabi root, which became mushy and black. This eventually resulted in wilting and death of the aboveground parts of the wasabi. The causal organism was isolated from the infected lesions and was identified as Erwinia carotovora subsp. carotovora based on the morphological, physiological and biochemical characteristics, and on the results of the Biolog program (Biolog Inc., U. S. A.). E. carotovora subsp. carotovora is the first described bacterium which causes bacterial soft rot on wasabi in Korea.

• 한국식물병리학회지
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• 제14권6호
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• pp.738-740
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• 1998

Bacterial soft rot was occurred on fruit of pepper that was grown in Chunceon, Kangwon province, Korea. The symptoms began as a small hole at 5 mm diameter, which made injury by a tobacco bud worm (Heliothis assulta). The affected fruit became soft and produced offensive odor. The causal organism was isolated from the diseased fruit and was identified as Erwinia carotovora subsp. carotovora based on the morphological, physiological and biochemical characteristics, and on the results of the Biolog program (Biolog Inc., U. S. A.). E. carotovora subsp. carotovora is the first described bacterium which causes bacterial soft rot on pepper in Korea.

• 한국식물병리학회지
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• 제14권6호
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• pp.741-743
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• 1998

A bacterial disease of pepper (Capsicum annuum L.) that rooted the stem nodes to black was found in pepper plants which cultivated in plastic house at Chungdo, Kyungpook, Korea in March, 1998. Bacterial isolates derived from the diseased peppers were pathogenic to potato, eggplant and Chinese cabbage but, was not pathogenic to chrysanthemum by artificial inoculation. On the basis of bacteriological characteristics and pathogenicity test on host plants, the causal organism of the node soft rot of pepper is identified as Erwinia carotovora subsp. carotovora and the name of disease is proposed as bacterial node soft rot of pepper.

• 한국식품영양과학회지
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• 제23권1호
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• pp.104-109
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• 1994

For Selection of powerful antagonistic bacteria for biological control of soil borne Erwinia rhapontici causing rot of the vegetables and fruit, excellent straints (S43, S62) were selected from rhizopere in vegetables root rot suppressive soil. Selected strains were identified to be Pseudomonas sp. with Apl 20NE kit tests. Optimum culture condition for the maximum production of antagonistic substance was determined , when isolate was cultured in 523 synthetic broth media at pH 7.0 and 30 during 3 days. Antagonistic substance productivity of isolated Pseudomonas sp. (S43, S62) in the fertilizer soil were increased to about 40-50% compared to that in the non fertilizer soil.

• 미생물학회지
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• 제26권1호
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• pp.60-66
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• 1988

Dynamics of bacterial communities and its colonization under aerobic gemp retting were observed in air lift fermentor as a closed system, unlike conventional hemp retting as an open system. Dried hemp which was harvested in both 1986 and 1987 was retted at room temperature. Predominant community was facultatively anaerobic Gram-negative rods, and its density was increased from $3.0\times 10^{7}$ cells/ml to $9.0\times 10^{8}$ cells/ml. The density of facultatively nanerobic Gram-positive fods was maintained at the lovel of $5.0\times 10^{6}$ cells/m, and this Gram-positive bacterial community was not participated in retting. In the Gram-negative bacterial community during the retting, five types of colonieswere developed at early stage of pH7.0-8.0, and thereafter, only three types were colonized till later stage, shich were identified as pectolytic strain Erwinia salicis, Erwinia tracheiphila and Enterobacter agglomerans. A community of facultatively Gram-negative rods was mainly proliferated in stems and dispersed into liquor after 6-8 hours. Retting was terminated within 70-80 hours.

• The Plant Pathology Journal
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• 제21권2호
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• pp.127-131
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• 2005

In this comparative study, the effects of temperature, pH, and bactericides on the growth of Erwinia pyrifoliae and Erwinia amylovora were investigated. The maximum temperature for the growth of both Erwinia species was estimated to be $36{\circ}C$. The maximum specific growth rates of E. pyrifoliae and E. amylovora were observed at $27{\circ}C$ and $28{\circ}C$, respectively, and no significant growth differences were shown at their optimum temperatures. However, at lower temperatures ranging from 12-$21{\circ}C$, E. pyrifoliae showed higher growth rates with doubling times shorter than those of E. amylovora. Distinct growth rates at these temperatures revealed that E. pyrifoliae is more cold-tolerant than E. amylovora. The optimum pH for the growth of both pathogens was 7.5 and growth was not seen at pH ${\le}$ 5.0 and ${\ge}$ 10.0. These results showed that the effect of pH on the growth of E. pyrifoliae and E. amylovora was similar. Minimum inhibitory concentrations (MICs) of copper sulfate, oxolinic acid, streptomycin, and tetracycline, which inhibited growth of E. pyrifoliae and E. amylovora, were determined. The strains of both pathogens were able to grow at 0.08-0.32 mM copper sulfate, but not at higher concentrations. However, none of the tested strains grew in the presence of oxolinic acid (0.001 mM), streptomycin (0.1 mM), and tetracycline (0.01 mM) concentrations. These results suggested that all strains of both Erwinia species were sensitive to tested bactericides and indicated no occurrence of resistant strains of E. pyrifoliae in Korea.

• Applied Biological Chemistry
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• 제42권3호
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• pp.199-204
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• 1999

배추로부터 연부균을 분리하여 조사한 결과 Erwinia chrysanthemi(Ech)로 동정되었으며 분리균 Ech PY35는 CMCase, pectinase, pectate lyase, protease 활성은 있었으나 hemicellulase 활성은 없었다. 배추와 감자의 조직에서 $24{\sim}48$시간 이내에 연부증상을 일으키며, 배추 조직보다 감자 조직에서 연부증상의 발병 진행속도가 느린 편이었다. 전자현미경관찰 결과 병원균의 식물 조직 내의 침투가 확인되었으며 이들이 분비한 세포벽분해효소에 의한 식물조직의 연부현상도 관찰되었다. 분리균의 체내 및 체외효소를 분리하여 CMC-SDS-PAGE에 의한 CMCase 직접활성 염색법을 이용하여 5종류의 CMCase isozyme으로 추정되는 활성밴드를 관찰할 수 있었다. 체내분비효소로 48 kDa, 34 kDa, 31 kDa의 3종류, 체외분비효소는 50 kDa, 29 kDa 2종류로 확인되었다.

• The Plant Pathology Journal
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• 제38권3호
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• pp.194-202
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• 2022

Erwinia amylovora and Erwinia pyrifoliae cause fire blight and black-shoot blight, respectively, in apples and pears. E. pyrifoliae is less pathogenic and has a narrower host range than that of E. amylovora. Fire blight and black-shoot blight exhibit similar symptoms, making it difficult to distinguish one bacterial disease from the other. Molecular tools that differentiate fire blight from black-shoot blight could guide in the implementation of appropriate management strategies to control both diseases. In this study, a primer set was developed to detect and distinguish E. amylovora from E. pyrifoliae by conventional polymerase chain reaction (PCR). The primers produced amplicons of different sizes that were specific to each bacterial species. PCR products from E. amylovora and E. pyrifoliae cells at concentrations of 10⁴ cfu/ml and 10⁷ cfu/ml, respectively, were amplified, which demonstrated sufficient primer detection sensitivity. This primer set provides a simple molecular tool to distinguish between two types of bacterial diseases with similar symptoms.