• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.109-115
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• 1996

국내 감자 연작 재배지에서 수집하여 분리동정한 더뎅이병원균인 Streptomyces scabies의 배양적, 형태적, 생리적 특성을 조사한 결과는 다음과 같다. 이병감자에서 분리된 균들은 병원성 균주와 비병원성 균주들로 구분되었고, 이들 간에는 뚜렷한 차이를 보였는데, 전형적인 병징을 나타내는 병원성균주는 비병원성균주와는 달리, 나선형의 포자사슬, 회색 포자, 멜라닌 색소를 생성하고 D-glucose, L-arabinose, D-fructose, D0mannitol, raffinose, rhamnose, sucrose, i-inositol, D-xylose 등의 탄소원을 이용하였으며, 또한 7% NaCl 및 streptomycin sulfate, crystal violet, olean domycin(10$\mu\textrm{g}$/ml, 100$\mu\textrm{g}$/ml)등의 항생물질에 감수성을 나타내었다.

• Applied Biological Chemistry
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• v.47 no.2
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• pp.164-169
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• 2004

In the course of our screening for biocontrol agent (BCA) against Streptomyces scabiei and S. turgidiscabies causing potato scab using 5,000 actinomtcete isolates, 9 antagonistic strains were selected as BCA candidates through in vitro and in vivo assay. An antagonistic strain, A020645 was highly resistant to some pesticides and antibiotics such as dazomet and mancozeb and showed high control value in vivo. Two bioactive compounds (compound A, B) were purified by anion exchange chromatography, solid phase (ODS) extraction, TLC and reverse phase HPLC. Their chemical structures are now thought to be nucleoside derivative as determined by $^1H-NMR$ data analysis. Their full chemical structures would be elucidated through $^{13}C-NMR$, HMQC and HMBC analyses. Further studies will be focused on fitness in soil and formulation of the BCA candidates.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.347-351
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• 2007

Potato scab is prevalent in all potato-growing areas of Jeju Island and causes economically significant losses. Streptomyces species are known as pathogens of potato scab. In this study, we analyzed the 16S rRNA sequences of Streptomyces spp, which are isolated from potato scab lesions in Jeju Island, and constructed 16S rRNA phylogenetic tree. All isolates were clearly differentiated into the genus Streptomyces, and the tree also showed that new scab-causing Streptomyces spp or not yet named species of Streptomyces are existed in Jeju Island, Korea.

• Research in Plant Disease
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• v.9 no.3
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• pp.137-144
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• 2003

This study was conducted to clarify developmental characteristics of scab in potato fields in Jeju island, Korea from 1995 to 1999. Occurrence of potato scab increased with repeated cultivaton of potato and high soil pH in the fields. Incidence of the disease was high as 54.8％ in the repeatedly cultivated potato fields but relatively low as 20.8~26.3% in the non-cultivated fields and in the fields where barley and Chinese cabbage were formerly cultivated. A total of 66 isolates were obtained from the diseased patato tubers and identified as Streptomyces scabies, S.turgidiscabies and S. acidiscabies. The isolation frequency of each Streptomyces species was 37.7%, 14.8% and 18.0%, respectively. The optimum temperature for mycelial growth of the Streptomyces spp. was $28~30^{\circ}C$, and the optimum pH for that 6~7.

• Research in Plant Disease
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• v.11 no.1
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• pp.66-71
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• 2005

The effect of medium components such as wheat bran, rice bran, oat meal, and soybean meal as basic ingredients and KH2PO4, glucose, and molasses as additives on mass production and anti-potato common scab activ ity of a streptomycete A020645 strain as a biocontrol agent (BCA) candidate was investigated. Of basicingredients, oat meal was the best one for mass poduction and enhancement of anti-potato common scabactivity. The biomass production of the active strain was more enhanced when 0.1-0.01.% glucose or molassesas additive were added into the basic medium. These information may have important implications in applying for effective formulation of BCA.