• 한국식물병리학회지
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• 제13권1호
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• pp.37-45
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• 1997

Disease incidence (DI), pre-emergence damping-off (PDO), days until the first symptom appeared (DUS), disease progress curve (DPC), and area under disease progress curve (AUDPC) were investigated in vivo after sowing ginseng seeds in each of 37 ginseng-cultivated soils which were sampled from 4 regions in Korea. Non linear fitting parameters, A, B, K and M, were estimated from the Richards' function, one of the disease progress models, by using the DI at each day from the bioassay. Inter- and intra-relationships between disease variables and stand-missing rate (SMR) in fields were investigated by using the simple correlation analysis. Disease variables of the root rot were divided into two groups: variables related to disease incidence, e.g., DI, AUDPC and A parameter, and variables related to disease progress, e.g., B, K and M parameters. DI, AUDPC, and DUS had significant correlations with SMR in ginseng fields, and then it showed that the disease development in vivo corresponded with that in fields. Soil samples could be separated into 3 and 4 groups, respectively, on the basis of the principal component 1 (PC1) and the principal component 2 (PC2), which were derived from the principal component analysis (PCA) of Richards' parameters, A, B, K and M. PC1 accounted for B, K and M parameters, and PC2 accounted for A parameter.

• 한국균학회지
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• 제45권2호
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• pp.132-138
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• 2017

작약에서 분리된 Cylindrocarpon destructans KACC44663 균주의 인삼에 대한 병원성 여부를 밝혀내고자 병원성 검정을 실시하였고 새로운 분류체계에 따른 균의 재분류를 위해 계통학적 유연관계를 분석하였다. 작약으로부터 분리된 KACC44663 균주가 인삼에 병을 일으키는 것을 확인하였고, 새로운 분류체계에 의해 I. radicicola species complex 내 위치하는 Ilyonectria robusta로 동정하였다. 이는 국내에서 타 기주로부터 분리된 병원균이 인삼에 뿌리썩음병을 일으키는 것을 증명한 첫 사례이다.

• Journal of Ginseng Research
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• 제19권2호
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• pp.181-187
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• 1995

Cylindvocarpon destmtalns isolate CY-92-01, pathogen of root-rot of Panax ginseng showed t the maximum mycelial growth on the Czapek solution agar among the thirteen kinds of media. Five isolates (Isolate CY-92-01, CY-92-03, CY-92-07, CY-94-01, CY-94-02) of C. destructan from various growth stages of p. ginseng recovered from several geographical sites also showed maximum growth in the Czapek-Dox broth compared with potato dextrose broth and V-8 juice broth. Rapid growth rate was maintained until 12 days after inoculation on the Czapek-Dox broth and mycelial weight was somewhat constant until 20 days. After 30 days of incubation, the mycelial weight began to decrease. The fungal growth occurred from 5$^{\circ}C$ to $25^{\circ}C$ and optimum temperature for growth was 2$0^{\circ}C$. Mycelial weight orderly decreased at 15, 25, 10, and 5$^{\circ}C$. Quantitative measurement was impossible at 5$^{\circ}C$. No fungal growth was occurred at the temperature higher than 3$0^{\circ}C$. Growth was observed at all tested pH ranges from 2.8 to 8.0. Optimum pH for growth was 4.0~5.0 followed by pH 3.3~3.5 and 5.4~6.0. The least growth occurred at pH 2.8.

• 식물병연구
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• 제25권3호
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• pp.131-135
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• 2019

Cylindrocarpon destructans causes ginseng root rot and produces radicicol that has an antifungal effect. In this study, we developed a method to detect this fungus using enzyme-linked immunosorbent assay (ELISA). Secreted proteins of C. destructans were used as antigens to obtain C. destructans-specific IgG from mouse. Out of 318 monoclonal antibodies generated from mouse, two antibodies (Cd7-2-2 and Cd7-2-10) showed highest specificity and sensitivity. Indirect ELISA using both antigens successfully detected C. destructans in soils, but direct ELISA using IgG conjugated with horseradish peroxidase failed to detect antigens in soils. The indirect ELISA developed here can efficiently detect the fungus and help manage ginseng root rot disease in fields.

• 한국연초학회지
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• 제7권2호
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• pp.123-128
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• 1985

The incitant of soft rot on burley tobacco leaves in the curing vinylhouse was identified as Erwinia carotovra subsp. carotovora on the basis of its physiological characters. The bacterium yew best at $25^{\circ}C$ and $30^{\circ}C$, but no growth was detectable at $40^{\circ}C$ in the nutrient broth for 24 hours period. Burley tobacco leaves inoculated with the bacteria (Ecc) produced typical soft rot lesions when the incubation temperature was 25 to $30^{\circ}C$ and the relative humidity was more than 8075, however, the lesion development was suppressed when the temperature was $40^{\circ}C$ and the relative humidity was below 80%. Significant negative correlation was found between hanging space in the curing vinylhouse and the incidence of soft rot on the tobacco leaves harvested in a rainy day regardless of streptomycin treatment.

• 한국약용작물학회지
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• 제25권1호
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• pp.1-9
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• 2017

Background: Some plants have harmful effects on fungi and bacteria as well as other plants. Incorporating such plant into soil as green manure is effective in reducing population densities of soil pathogens. Methods and Results: Twenty-three species of green manure crops were cultivated after the harvest of 6-year-old ginseng and then incorporated into the soil at the flowering stage. The following year, the root rot ratio of 2-year-old ginseng and soil chemical properties were investigated. In the absence of green manure addition, the $NO_3$ content, electric conductivity (EC), and K content decreased by 95%, 79% and 65%, respectively. In the presence of green manure addition, $P_2O_5$ and $NO_3$ contents reduced by 41% and 25%, respectively. The "survived root ratio" of 2-year-old ginseng significantly increased by 56.2%, 47.5%, and 47.3%, in the Sorghum sudanense, Ricinus communis and Helianthus tuberosus treatment, respectively. In addition, there was a significant increase in the "survived root ratio" in the Secale cereale, Chrysanthemum morifolium, Atractylodes macrocephala, and Smallanthus sonchifolius treatments. The "survived root ratio" of ginseng showed a significant positive correlation with the soil pH and a negative correlation with the $NO_3$ contents, and EC. Conclusions: Cultivation of plant form the Chrysanthemum family as green manure, using mainly the rhizomes was effective for the control of root rot disease of ginseng.

• 식물병연구
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• 제28권4호
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• pp.204-208
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• 2022

새싹인삼의 뿌리썩음병 억제제로서 과산화수소의 활용 가능성을 구명하고자 항진균 활성효과와 묘삼 소독효과를 연구한 결과, 과산화수소는 300 mg/l의 농도에서 1×10⁷ conidia/ml 농도의 Cylindrocarpon destructans 균총을 80% 이상 억제시켜 항진균 활성을 나타내었고 인위적으로 병원균에 감염시킨 묘삼의 유병율을 20% 이하로 억제시켜 소독효과가 매우 높았다. 결과적으로 과산화수소 희석수 300 mg/l를 14일에 걸쳐 분무처리하였을 때, 인위적으로 병원균에 감염된 새싹인삼의 뿌리썩음병 발생수율이 72.1%로 무처리의 발생수율 87.2%에 비해 다소 억제되었다. 그러나, 과산화수소의 주기적인 살포가 새싹인삼의 생육 부진을 다소 유발하였다. 추가 연구로서 뿌리썩음병의 방제에 효과적이고 새싹인삼에 안전한 과산화수소의 처리방법 개발이 요구되었다.

• 미생물학회지
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• 제20권2호
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• pp.73-79
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• 1982

Among 131 isolates of Strptomyces obtained from ginseng cultivating soil, the two isolates ST59 and ST129 showing high antagonistic activity to Fusarium solani(Mart.) Appel & We. causing ginseng root rot were identified. The two isolates were identified Streptomyces alboniger Porter, et al. and Strptomyces reseolilacinus Pridham, et al., respectively, based on mrophology, cultural, and physiological characteristics on various culture media. Spore chains of ST59 and ST129 were flexuous(RF) and coiled(S). Spore surfaces of two isolates were all smooth. Aerial mass color of ST59 was white series and ST129 red series.

• The Plant Pathology Journal
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• 제27권4호
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• pp.333-341
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• 2011

Two antifungal bacteria were selected from forest soils during the screening of microorganisms antagonistic to Cylindrocarpon destructans, a cause of ginseng root rot. The antifungal bacteria were identified as Bacillus subtilis (I4) and B. amyloliquefaciens (yD16) based on physiological and cultural characteristics, the Biolog program, and 16S rRNA gene sequencing analyses. Antagonistic activity of both bacterial isolates to C. destructans increased with increasing temperature. More rapid starch hydrolytic activity of the bacteria was seen on starch agar at higher temperatures than at lower temperatures, and in the higher density inoculum treatment than in the lower density inoculum treatment. The bacterial isolates failed to colonize ginseng root the root tissues inoculated with the bacteria alone at an inoculum density of $1{\times}10^6$ cfu/ml, but succeeded in colonizing the root tissues co-inoculated with the bacteria and C. destructans. Scanning electron microscopy showed that the pathogen was damaged by the low-density inoculum treatment with the bacterial isolates as much as by the high-density inoculum treatment. Both bacterial isolates were more effective in reducing root rot when they were treated at a concentration of $1{\times}10^6$ cfu/ml than at $1{\times}10^8$ cfu/ml. Also, only the former treatment induced prominent wound periderm formation, related to structural defense against pathogen infection. The results suggest that the bacterial antagonists may have high potential as biocontrol agents against ginseng root rot at relatively low-inoculum concentrations.

• Mycobiology
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• 제44권1호
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• pp.63-65
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• 2016

Cylindrocarpon destructans causes root rot disease in ginseng and can survive for a long time, producing chlamydospores. We optimized conditions to induce chlamydospore production from the conidia of C. destructans, isolated from Korean ginseng. This will provide the basis for testing the efficacy of control agents targeting these chlamydospores.