Background: Cylindrocarpon destructans (Zins) Scholten is an important pathogenic fungus that causes ginseng root rot in many ginseng growing areas in China. Although C. destructans have been studied worldwide, research on its chemotaxis towards ginseng (Panax ginseng C. A. Meyer) root exudates in the rhizosphere remains limited.Methods and Results: In this study, we collected ginseng root exudates with three different polarities from three-year-old ginseng roots, and performed chemotaxis and spore germination assays to investigate the ability of these exudates to induce the response in C. destructans. The results showed that, compared with other conditions, when C. destructans cultivated at 20°C and a pH of 6 exhibited a strong positive chemotactic response toward 2 ㎎/ℓ aqueous phase, 20 ㎎/ℓ butanol phase, and 0.2 ㎎/ℓ petroleum ether from ginseng root exudates, the chemotactic moving indexes were 0.1581, 0.1638 and 0.1441, respectively. In addition, the spore germination rate with optimal chemotactic parameters were 48%, 53%, and 41% in the aqueous phase, butanol phase and petroleum ether groups, respectiviely, which were significantly higher than that in the control group (23%) (p < 0.05). The mycelial growth rate with optimal chemotactic parameters increased with culture time, and the maximum growth rates in the aqueous phase, butanol phase and petroleum ether groups were 0.425, 0.406 and 0.364 respectively, on the 4th day. The optimal chemotactic parameters were 39.73 ㎎/50 ㎎/ℓ , 48.93 ㎎/50 ㎎/ℓ , and 31.43 ㎎/50 ㎎/ℓ , in aqueous phase, butanol phase and petroleum ether respectively, from ginseng root exudates, compared with 5.5 ㎎/50 ㎎/ℓ , in the control group.Conclusions: The present study revealed that certain ginseng root exudates containing chemical attractants act as nutritional sources or signals for C. destructans and support its colonization of ginseng roots.

Background : Ginseng widely cultivated as a major medicinal herb in Korea, is economically important crop for farmer. Ginseng root disease caused by soil borne pathogens is main factors restricting the quantity and quality of ginseng. The disease can result in harvest loss of up to 20~70% and limits the replanting of ginseng under same field for long time. The traditional control method of agrochemical use is not recommend to control soil borne disease because of difficulty in use and unstable effect. The objective of this study was to evaluate the efficacy of several antagonistic microbes for developing biological control method of ginseng root rot. Methods and Results : To select biocontrol agents against ginseng soil borne disease, several bacteria were isolated from ginseng root and rhizosphere soil evaluated in vitro screening of antifungal bacterial against ginseng root pathogens. Two antagonistic bacteria, ES17 and CJ4, showed the strongest inhibition effect against ginseng root pathogen. In the pot experiment under greenhouse conditions, ginseng seedling dipped in bacterial suspension at inoculum density of 106 cfu/ml for 1 hour were planted in pot containing inoculum. Control effect was examined depend on disease severity index at 30 days after inoculation. Ginseng root treated with CJ4 and ES17 isolate reduced root rot disease development on the ginseng root with degrees of control efficacy of 85% and 70%, respectively. Conclusion : Two biocontrol agent, Burkholderia ambifaria CJ4 and Paenibacillus strain ES17, had strong antifungal efficacy against ginseng soil borne pathogens. These results obtained from in vitro test and pot experiment suggest the potential applicability of the biocontrol agent to control ginseng root rot caused by various soil borne pathogens.

Background : Ginseng (Panax ginseng C.A. Meyer) is one of the most important medicinal plants in Korea, but its yields are often reduced by a variety of root pathogens. The root rot of ginseng is a destructive soil-borne disease caused by Cylindrocarpon destructans (teleomorph: Ilyonectria radicicola). To monitor contamination with C. destructans in ginseng harvested in 2015 were sampled from 57 different growing fields. The spore number of C. destructans was quantified by use of a specific primers and selective media (radicicol) in soils of ginseng fields. Methods and Results : The ginseng samples were surface-sterilized and placed on potato dextrose agar plates for 7 day incubation at 20℃. Emerging fungal colonies were counted primarily based on colony and conidia morphology. Further species level identification was confirmed by ITS rDNA sequencing. For quantification of the soil-borne C. destructans, the genomic DNA was extracted from the soil using a NucleoSpin soil kit (MN, Germany). Density of C. destructans was determined by species specific real time PCR (qPCR). The qPCR was completed by running a melting curve analysis. Conclusion : The C. destructans associated with root rot disease of ginseng were detected in more than 60% in pyeongtaek-1, pochenon-1, jecheon-1, chungju-1 and jinan-4. As results of the study, the correlation between pathogen density and identification clearly clarified in the soil.

Background : Ginseng root rot caused by soil-borne pathogens, Cylindrocarpon destructans and Fusarium solani, is a major factors of replanting failure in ginseng cultivation. Some of the phenolic compounds detected in the soil of commercially cultivated American ginseng could inhibit the seed germination and seedling growth of American ginseng. Our study is to investigate the causes of replanting failure of ginseng by overhead flooding treatment and soil incorporation of ginseng fine root in soil infected with root rot pathogens. Methods and Results : To make soil occurring continuous cropping injury, 2-year-old ginseng infected with Cylindrocarpon destructans replanted in soil cultivated ginseng for 5 years. Treatment are as follows: 1) control, 2) water of 2ℓ was irrigate infected soil of 20ℓ, 3) ginseng fine root of 20g was mixed with infected soil of 20ℓ. Soil pH was increased, while other inorganic components were significantly reduced by overhead flooding treatment. Soil incorporation of ginseng fine root decreased soil pH, but increased EC, NO3, P2O5 and K, meanwhile, did not affected changes in organic matter, calcium, magnesium, sodium. Irrigation treatment in soil occurring replanted failure promoted distinctly above-ground growth of ginseng, and inhibited the occurrence of root rot because inorganic nutrient like NO3, P2O5 and K were decreased to optimal levels, and the density of soil pathogens could be reduced. Growth of ginseng was not inhibited, while root rot was promoted by soil incorporation of ginseng fine root. Conclusion : Irrigation treatment was effective in promoting the growth of ginseng and inhibited root rot distinctly. Ginseng fine root remaining in the soil after ginseng harvest did not affect the above-ground growth of ginseng, while promoted the occurrence of root rot.

Background: Crop rotation plays an important role in improving soil chemical properties, minimizing the presence of disease pathogens, and assists in neutralizing autotoxic effects associated with allelochemicals. Methods and Results: Five rotation crops of sudan grass, soybean, peanut, sweet potato, and perilla were cultivated for one year with an aim to reduce yield losses caused by repeated cropping of ginseng. In 2-year-old ginseng grown in the same soil as a previous ginseng crop, stem length and leaf area were reduced by 30%, and root weight per plant was reduced by 56%. Crop rotation resulted in a significant decrease in electrical conductivity, NO3, and P2O5 content of the soil, whereas organic matter, Ca, Mg, Fe, Cu, and Zn content remained-unchanged. Soil K content was increased following crop rotation with sudan grass and peanut only. Rotation with all alternate crops increased subsequent ginseng aerial plant biomass, whereas root weight per plant significantly increased following crop rotation with perilla only. A significant positive correlation was observed between root rot ration and soil K content, and a significant negative correlation was observed between ginseng root yield and the abundance of actinomycetes. Crop rotation affected the soil microbial community by increasing gram negative microbes, the ratio of aerobic microbes, and total microbial biomass whereas decreases were observed in actinomycetes and the ration of saturated fatty acids. Conclusions: In soil exhibiting crop failure following replanting, crop rotation for one year promoted both soil microbial activity and subsequent ginseng aerial plant biomass, but did not ameliorate the occurrence of root rot disease.

Three Supreme Court’s rulings are reviewed in this paper. They are all about the similar cases. Someone asked the other person to withdraw a specific sum of money from his account, but the latter(the delegated person) withdrew an excess and took it. What sort of crime should be assigned to him? The ruling A presents the view of fraud by electronic instrument. It says that defendant took illegal gain through inputting unauthorized data into ATM. Another judgement, the ruling B, sets forth the different view. It declares the breach of trust, saying that defendant violated his duty. The final judgement, the ruling C, also deals with the case alike. However it supports the decision of the lower court to give defendant the embezzlement verdict. To sum up, there are contradicted rulings on the same case! What solution could be made to handle such confusion. It is the task of this paper. The conclusion is the crime of embezzlement, it means that the ruling C is appropriate. This paper presents its grounds and arguments and hopes for readjusting The Supreme Court’s ruling forward.

Background : Cylindrocarpon root rot, caused by Cylindrocarpon destructans and Fusarium solani, is a major disease which lead to replanting failure in ginseng garden. Chlamydospores of C. destructans, generated by poor environmental condition, can survived more than ten years in soil without host plant, ginseng. Density of soil pathogens gradually decreased as the progress of time since ginseng was harvested. Methods and Results : Soil chemical properties was analyzed from soil samples of 43 regions in farmer’s ginseng garden to study the variation of content and the correlation among inorganic contents. Soil samples of 24 regions was also analyzed to study correlation between progressed-year after ginseng harvest and soil chemical properties. Variation of soil chemical properties in descending order was Fe, Zn, P2O4, NO3, Mn. The content of Fe and Zn were great variation among inorganic chemicals of soil of farmer’s field. Electrical conductivity to induce physiological demage in excessive concentration showed highly significant positive correlation with the content of NO3 and K. As the progress of year after ginseng harvest, the content of organic matter and zinc was increased, while pH and Na were decreased in farmer’s field to cultivate ginseng. There were highly significant positive correlation between the progress of year after ginseng harvest and zinc content in farmer’s field to cultivate ginseng. Ratio of root rot of 2-year-old ginseng showed significant positive correlation with K content, and negative correlation in experimental field cultured by six rotation crops for one year. Conclusion : Root rot by soil pathogens was closely related with the content of potassium and zinc in soil chemical properties.

Background : Root diseases caused by Cylindrocarpon destructans and Fusarium solani decrease the yield and quality of ginseng. Cylindrocarpon root rot is a major disease caused by replanting failure in ginseng garden. Methods and Results : Solarization was done in the infested soil of the greenhouse for summer season (from July 24 to Autumn 31, 2014) after putting green manure (Sudan grass) and calcium cyanamide (CC) into the soil. Mycelium and conidia of C. destructans died at 4 0℃ after 15 hours, and 45℃ after 5 h, but it did not die at 35℃ after 15 h. Those of C. destructans died after keeping it for 2 hours daily at 40℃ for 9 days, and 45℃ for 8 days, but did not die at 38℃ for 9 days. Maximum soil temperature was 55.4℃ in 5 cm depth, 48.7℃ in 10 cm, 44.7℃ in 15 cm, 42.5℃ in 20 cm, and 31.9℃ in 30 cm by putting green manure into the soil and solarization. Reduction of sudan grass increased electrical conductivity (EC), organic matter, P2O5, K, and Mg, while decreased pH, NO3-N, and Na. Addition of calcium cyanamide and urea gave a negative effect on the growth of ginseng because EC and NO3-N were increased excessively than the optimal range. Solarization using green manure mixed with CC was the most effective in decreasing soil-borne pathogens of 2-year-old ginseng. But the root disease that occurred between single treatment of sudan grass and the treatment mixed with calcium cyanamide showed not a significant different. Addition of calcium cyanamide showed the decrease of root weight because leaves were dead early by a excessive increase of EC and NO3-N. Conclusion: Soil disinfection using green manure and solarization in greenhouse was effective in inhibiting root rot, however, it did not completely kill the soil-borne pathogens.

Background: Root diseases caused by Cylindrocarpon destructans and Fusarium solani decrease the yield and quality of ginseng. Cylindrocarpon root rot is a major disease caused by replant failure in ginseng fields. Methods and Results: Solarization of infested greenhouse soil was carried out during the summer season after applying green manure (Sudan grass) and Calcium Cyanamide (CC) on the soil. Mycelium and conidia of C. destructans died at 40℃ after 15 h, but they did not die at 35℃ after 15 h. They also died after keeping the soil at 40℃ for 2 h daily for 9 days, and at 45℃ for 8 days, but they did not die at 38℃ for 9 days. Maximum soil temperature was 55.4℃ at 5 ㎝ depth, 48.7℃ at 10 ㎝, 44.7℃ at 15 ㎝, 42.5℃ at 20 ㎝, and 31.9℃ at 30 ㎝ by incorporating green manure into the soil and using solarization. Solarization using green manure mixed with CC was the most effective in decreasing soil-borne pathogens of 2-year-old ginseng. However, the addition of CC decreased the root weight due to the increase in EC and NO3-N. Conclusions: Soil disinfection using green manure and solarization in a greenhouse environment was effective in inhibiting root rot, however, it did not completely kill the soil-borne pathogens.

Background : Ginseng is mainly grown as a break crop in paddy fields after rice has been cultured for approximately 4 - 5 years, because it reduces the negative effects of continuous rice cropping. However, physiological disorders, such as leaf discoloration, occur in ginseng grown in paddy fields with poor drainage and excessive levels of inorganic components. Methods and Results : This study investigated the effect of ridge height on the growth characteristics and yield of 6 year old Panax ginseng. Ridge height was varied by making 20, 30, and 40 ㎝ high ridges in a pooly drained paddy field. Soil moisture content decreased, while electrical conductivity (EC) as the ridge height increased. The NO3, K, Ca, Mg, and Na levels also rose as ridge height increased, but organic matter and P2O4 levels did not. The leaf discoloration ratio rose as the ridge height increased, and root yield reached a peak when the ridge height was 30 ㎝. Conclusion : A ridge height of 30 ㎝ in poorly drained paddy field improved ginseng growth by reducing leaf discoloration and increasing root survival, owing to more suitable soil moisture and EC levels.

To study the effect of crop rotation on the control of ginseng root rot, growth characteristics and root rot ratioof 2-year-old ginseng was investigated after the crops of 18 species were cultured for one year in soil contaminated by thepathogen of root rot. Fusarium solani and Cylindrocarpon destructans were detected by 53.2% and 37.7%, respectively, frominfected root of 4-year-old ginseng cultivated in soil occurring the injury by continuous cropping. Content of NO3, Na, andP2O5 were distinctly changed, while content of pH, Ca, and Mg were slightly changed when whole plant of crops cultured forone year were buried in the ground. All of EC, NO3, P2O5, and K were distinctly increased in soil cultured sudangrass, pea-nut, soybean, sunnhemp, and pepper. All of EC, NO3, P2O5, and K among inorganic component showed negative effect onthe growth of ginseng when they were excessively applied on soil. The growth of ginseng was promoted in soil cultivatedperilla, sweet potato, sudangrass, and welsh onion, while suppressed in Hwanggi (Astragalus mongholicus), Deodeok(Codonopsis lanceolata) Doraji (Platycodon grandiflorum), Gamcho (Glycyrrhiza uralensis), Soybean. All of chicory, lettuce,radish, sunnhemp, and welsh onion had effective on the inhibition of ginseng root rot, while legume such as soybean,Hwanggi, Gamcho, peanut promoted the incidence of root rot. Though there were no significant correlation, NO3 showedpositive correlation, and Na showed negative correlation with the incidence of root rot.

Physiological disorders such as symptoms in leaf colored with brown spots are so many occurred in ginseng garden cultivated with paddy soil. This study was carried out to inhibit the symptoms of brown-colored leaf in 3-year-old ginseng by fertilizing calcium hydroxide [Ca(OH)2] of 100 ~ 400 ㎏ per 10a on paddy soil before transplant of seedling. Soil pH was rapidly increased, while Fe was decreased in soil by the increase of application level of calcium hydroxide. Soil pH was increased from 4.53 to 6.18 when calcium hydroxide was fertilized at level of 100kg per 10a. The content of Fe in ginseng leaf was decreased more than the control by fertilizing calcium hydroxide in soil. Ratio of brown-colored leaf and plant height and leaf area were decreased by the increase of calcium hydroxide. Ratio of survived root and yield of root showed the peak at the application level of 100 ㎏ per 10a, and both of them were gradually decreased by the increase of calcium hydroxide. The decrease of missing plant rate above the application level of 200 ㎏ per 10a had a negative effect on the decrease of yield of root.