인삼 조사포닌과 인삼즙액이 인삼 근부패를 일으키는 병원균 Fusarium solani와 Erwinia carotovora의 생장과 증식 및 포자발아에 미치는 영향을 조사하여 다음과 같은 결과를 얻었다. 1. 인삼 조 Saponin의 농도가 증가됨에 따라 F. solani의 대형분생포자의 발아율은 억제 되었으며 500 ppm 이상 첨가시 현저하게 억제 되었다. 2. 토양 추출액은 초기에 F. solani의 포자 발아를 억제하는 효과가 있었으나 24시간후에는 무효화되었다. 3. 인삼 조 Saponin의 첨가 농도가 증가됨에 따라 F. solani의 포자형성량이 감소되었으며 고체배지에서 이러한 현상은 더욱 뚜렷하게 나타났다. 4. 인삼 Saponin을 첨가 했을시 균사생장량은 약간 감소되었으나 농도에 따른 감소율은 인정되지 않았다. 5. 인삼 조 사포닌은 농도가 증가 될 수록 F. solani의 Colony 형성을 억제하였으나 인삼즙액은 농도가 증가될수록 현저하게 F. solani의 Colony수를 증가시켰다. 6. 인삼 조 Saponin과 인삼즙액 모두 E. carotovora의 생장을 촉진시켰다.

Background : Development of new real-time PCR diagnosis method for simultaneous diagnosis of Cylindrocarpon destructans and Fusarium solani, causative fungi of ginseng root rot disease. C. destructans and F. solani are known to be the major pathogens of ginseng root rot disease. Root rot caused by these pathogens is a disease that is difficult to control because the disease progresses slowly and it is difficult to diagnose early and even when symptoms of plant seeding are present, the disease is already spread in the roots. Diagnostic methods to detect the presence or absence of ginseng roots rot fungi in soil before ginseng cultivation are currently being used as a method for controlling. However, commercialized soil extraction kits and PCR diagnostics have cost, diagnostic time, and single diagnostic problems, and need to develop new diagnostic methods. Methods and Results : Primers and probes in the beta-tubulin 2 gene were designed for species-specific detection. In silico analysis, the detection rate of C. destructans was 100% and the detection rate of F. solani was 95%. The multiplex real time PCR optimization conditions including the internal control were established. The analytical sensitivity using positive samples was 10 copies/㎕ for C. destructans and 10 copies/㎕ for F. solani. As a result of performance comparison test with conventional PCR diagnosis methods, it was confirmed that the developed multiplex real time PCR method has the same or better performance in terms of sensitivity. In the developed soil extraction kit, the extraction time was reduced and the extracted DNA quality was improved, compared to the used soil extraction kit. Conclusion : From the above results, we expect that the developed C. destructans / F. solani multiplex real time PCR diagnosis method and soil extraction kit will be useful for real-time monitoring of ginseng root rot pathogenic fungi in the soil of ginseng cultivation area and diagnosis of suitability of ginseng cultivation area.

From the soils of soybean fields in Cotton Branch Station (CBS) and Pine Tree Station (PTS), Arkansas, USA, various single spore isloates of sudden death syndrome (SDS) pathogen were obtained on modified Nash ＆ Snyder's medium (MNSM) with dilution plating technique and transferred to potato dextrose agar (PDA) medium to identify the cultural colony shape. The colony shapes of these isolates resembled F. solani isolate 171 which was white and chalky shaped on MNSM and most of them had unique form of morphology which produced white margin and blue center colony on PDA. Although, some of these isolates had more dark blue or showed slightly different color, all isolates that were selected randomly for green-house inoculation assay produced typical foliar symptoms on leaves of soybean, Hartz 6686. To determine the genetic differences among the isolates, mitochondrial DNA restriction fragment length polymorphism (RFLP) was conducted with fourty isolates from both fields, using mtDNA probes, 2U18 and 4U40, derived from Colletotrichum orbiculare. We obtained distinctive RFLPs in each treatment of restriction enzyme, EcoRI and HaeⅢ. Isolates, 11-2-5 and 14-3-1-1, from CBS and isolates, 104-3-1-2 and 701-1-5-1, from PTS showed different band patterns from 171 in both or in either treatment of restriction enzymes. Even if some of these isolates showed heterogeneous, they were more closer to 171 than PN603. And, also, rest of the thirty-six isolates had exactly same polymorphisms as 171 in each treatment of restriction enzyme. Although, some of the isolates showed the different morphological shape on PDA and slightly different band patterns on RFLPs, all of the isolates selected on MNSM due to their distinctive colony shape from other fungi produced the typical foliar symptoms on soybean leaves in greenhouse inoculation assay. It might be suggested that these isolates were not genetically different from check isolate 171 and they were unique strain of F. solani

In order to identify the responses of Korean soybean cultivars to sudden death syndrome (SDS), forty-two Korean cultivars and three check cultivars (Hartwig and PI 520733 are resistant; Hartz 6686 is susceptible) were tested with sorghum seed inoculum infested with Fusarium solani f. sp. glycines isolate 171 in the greenhouse. This isolate has blue pigment cultural shape on potato dextrose agar (PDA) medium. All Korean cultivars inoculated with F. solani isolate 171 showed the typical SDS symptoms and disease severity on soybean leaves in each cultivar varied at 4 weeks after inoculation. Nine cultivars were included in the most SDS susceptible group and six cultivars were included in the most susceptible group based on Duncan＇s multiple range tests (P~leq 0.05). In results of the LSD analysis for SDS the resistant group, a total of twenty-five Korean cultivars were included in the same SDS resistant group as PI 520733 or Hartwig and fourteen Korean cultivars were included in the same SDS susceptible group as Hartz 6686. In the second experiment, ten Korean cultivars, ten U.S. cultivars, and one introduced line were compared in the same way as the first experiment Disease severity ranking of check cultivars, Hartwig, PI 520733, and Hartz 6686, were the same as in the first experiment. Within Korean cultivars, seven cultivars showed the consistent severity proportions of leaf symptoms. Disease rankings of these cultivars in this experiment were the same as those in the first experiment. Three US cultivars: Hartwig, Hartz 5454, and Forrest, three Korean cultivars： Keunolkong, Myeongjunamulkong, and Jinpumkong 2, and one introduced line, PI 520733, were included in the highest SDS resistant group. Shinphaldalkong 2, Milyang 87, and Samnamkong consistently showed the highest SDS susceptibility in both experiments. Average disease severity in the first and the second experiment were 49.56% and 45.39%, respectively.