• Korean Journal of Organic Agriculture
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• v.24 no.3
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• pp.435-451
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• 2016

The objective of the present study was to perform a comparative analysis of the chemical properties of the cultivation site soil and growth characteristics of organically and conventionally cultivated ginseng (Panax ginseng C. A. Meyer). Organically and conventionally cultivated ginseng samples (4-, 5-, and 6-year-old) were collected from 52 fields at 14 locations throughout Korea. The samples were collected over three years from 2013 to 2015, with the collection period between October and November of each year. In order to increase the yield of organically cultivated ginseng, the amount of nutrients was increased to match that of the conventional cultivation system, which highlights the need for proper management in accordance with the standards for chemical properties of soil. Growth duration of organic ginseng was ${\geq}60days$ shorter than that of conventional ginseng and its average yield per 1ha was 60% than that of conventional ginseng. Root weight of organically cultivated ginseng was approximately 54% that of conventionally cultivated ginseng. Rhizome diameter and body shape index of organically cultivated ginseng were lower than those of conventionally cultivated ginseng, indicating that organically cultivated ginseng was thinner and longer than conventionally cultivated ginseng. Root length was greater in 5-year-old conventionally cultivated ginseng with a low percentage of paddy-upland rotation fields. The number of rootlets was lower in 5- and 6-year-old organically cultivated ginseng with a high percentage of direct seeding cultivation. Dry weight was distinctly lower in 5- and 6-year-old organically cultivated ginseng with early defoliation than that of conventionally cultivated ginseng. Incidences of notched belly and root rot tended to be higher in conventional cultivation, with the incidence of notched belly being distinctly higher in 4- and 6-year-old roots and root rot being more prevalent in 5- and 6-year-old roots. Red discoloration and eelworm damage, which are highly affected by soil moisture, were most common in the organically cultivated 4-year-old roots. Organically cultivated ginseng showed early defoliation than conventionally cultivated ginseng, as a result, its yield and weight were low, while the incidence of physiological disorders was low. In order to increase the yield of organically cultivated ginseng, studies on cultivation technology that can overcome early defoliation, as well as soil moisture management that can minimize physiological disorders, are required.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.56-62
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• 1989

Antagonistic effects of Streptomyces species aganinst Fusarium solani causing ginseng root rot were investigated in terms of chitinase activity and growth inhibition in vitro. Among 131 isolates of streptomycetes obtained from ginseng cultivating soil, 9 isolates producing large clear zone around the colony on a chitin agar medium were selected for further study. All 9 isolates produced chitinase in a range from 0.10 to 0.38 U lysing cells of F. solani and inhibited germination of the conidia. In the ten-fold condentrated culture filtrate of S. alboniger ST59 and S. roseolilacinus ST129, the number of conidia of F. solane was reduced to about 20% of original count within 14 days. When S. alboniger ST59 and F. solani were grown simultaneously in the mineral saly medium, chitinase activity increased with incubation period, whereas mycelial volume of F. solani decreased. In a chitin added mineral salt medium, chitinase activity increased during the first four days and maintained steady level until the 8th day, and increased thereafter. S. alboniger ST59 lysed mycelia, conidia and even chlamydospores of F. solani. It is probable that the antagonistic activity of this streptomycete against F. solani is the lysis of fungal cell wall by streptomycete producing chitinase affected by antifungal substances.

• Journal of Ginseng Culture
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• v.6
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• pp.51-79
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• 2024

In the 1970s and 1980s, during the nascent phase of ginseng disease research, efforts concentrated on isolating and identifying pathogens. Subsequently, their physiological ecology and pathogenesis characteristics were scrutinized. This led to the establishment of a comprehensive control approach for safeguarding major aerial part diseases like Alternaria blight, anthracnose, and Phytophthora blight, along with underground part diseases such as Rhizoctonia seedling damping-off, Pythium seedling damping-off, and Sclerotinia white rot. In the 1980s, the sunshade was changed from traditional rice straw to polyethylene (PE) net. From 1987 to 1989, focused research aimed at enhancing disease control methods. Notably, the introduction of a four-layer woven P.E. light-shading net minimized rainwater leakage, curbing Alternaria blight occurrence. Since 1990, identification of the bacterial soft stem rot pathogen facilitated the establishment of a flower stem removal method to mitigate outbreaks. Concurrently, efforts were directed towards identifying root rot pathogens causing continuous crop failure, employing soil fumigation and filling methods for sustainable crop land use. In 2000, adapting to rapid climate changes became imperative, prompting modifications and supplements to control methods. New approaches were devised, including a crop protection agent method for Alternaria stem blight triggered by excessive rainfall during sprouting and a control method for gray mold disease. A comprehensive plan to enhance control methods for Rhizoctonia seedling damping-off and Rhizoctonia damping-off was also devised. Over the past 50 years, the initial emphasis was on understanding the causes and control of ginseng diseases, followed by refining established control methods. Drawing on these findings, future ginseng cultivation and disease control methods should be innovatively developed to proactively address evolving factors such as climate fluctuations, diminishing cultivation areas, escalating labor costs, and heightened consumer safety awareness.

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.357-363
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• 2012

Ginseng (Panax ginseng C. A. Meyer) is an economically important crop in Korea. While the consumption of the crop is gradually increasing, the yield is decreasing due to the injury of continuous cultivation or infection of soil-borne fungal pathogens such as Cylindrocarpon destructans, Fusarium solani, Rhizoctonia solani and Sclerotinia nivalis. In order to find promising biocontrol agents, we have isolated 439 soil bacteria from ginseng cultivated soil and tested their antifungal activities against ginseng rot pathogens. Among them, 3 strains were finally selected and tested for the elucidation of their genetic and biochemical properties. They were identified as Bacillus amyloliquefaciens using phylogenetic analysis based on 16S rRNA gene sequences. Moreover, all selected strains showed positive reaction for PCR detection targeting biosynthetic gene sequences of iturin A and surfactin. The results provided promising evidences that the bacterial strains isolated from ginseng cultivated soil can be novel biocontrol agents for ginseng cultivaion.

• The Korean Journal of Mycology
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• v.39 no.1
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• pp.16-21
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• 2011

Ginseng root rot caused by Cylindrocarpon destructans is one of the most destructive diseases of ginseng(Panax ginseng). We analyzed the features of the species through pathogenicity test and genetic diversity analysis of C. destructans in Korea, for its application as basic data to attempt for effective control. C. destructans isolated from rotted ginseng roots exhibited a variety of colonial colors on media. It was assumed that there may exist genetic diversity in the population by the diversity of pathogenicity among isolates observed when artificially inoculated into ginseng roots. Pathogenicity tests using ex vivo wound inoculation with agar mixture inoculation on ginseng roots were performed similar results as were observed appear to be useful for rapid pathogen inspection. According to RAPD analysis results, Korean C. destructans isolates formed a single genetic group which can be distinguished readily from closely related other fungi. C. destructans group was divided into two small groups. Therefore, we were able to confirm pathogenicity and genetic difference between the isolates in each of the groups of the pathogen.

• Journal of Ginseng Research
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• v.3 no.2
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• pp.156-167
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• 1979

Physiological characteristics of Panax ginseng were reviewed in relation to temperature. According to the old literatures and records of cultivator's experiences it was elucidated that ginseng plants require light but hate high temperature and that the cultural methods were developed to content two characteristics in contradiction. Low temperature (cool climate) during growing season seems (or ginseng to be essential and to escape from the extreme coldness according to air and soil temperature of natural habitat and cultivated area. Optimum temperature of dehiscence (15∼below 20$^{\circ}C$) is a little higher than that of germination (10∼15$^{\circ}C$). Optimum temperature for growing of new buds (18∼20$^{\circ}C$) is similar to that for growing after emergence (17∼21$^{\circ}C$). Dormancy of both matured embryo and new buds is broken at the same temperature (2∼3$^{\circ}C$). It seems reasonable that optimum temperature of photosynthesis (22$^{\circ}C$) is similar to that of growth. Respiration quotients of various organs or of whole plant ranged from 1.7 to 3 incrased with high temperature. Respiratory consumption and oxygen limitation seem to be potential factors to induce decay during dehiscence and germination of seeds and root rot in fields. Research on organ differentiation. photosynthesis, respiration and growth with age is needed for the development of cultivation methods.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.396-403
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• 2014

Ginseng (Panax ginseng C. A. Meyer) is an economically valuable pharmaceutical crop in Korea. In order to find promising biocontrol agents for soil-borne fungal pathogens which infect ginseng roots, we have isolated actinomycete, BK185 from soil. The isolate was investigated for the antifungal activity against to ginseng rot pathogens prior to testing genetic and chemical properties. The strain was identified as Streptomyces sp. using phylogenetic analysis based on 16S rRNA gene sequence. The most closely related species was S. sporoclivatus and S. geldanamycininus with high similarities (>99%). The isolate, BK185 showed positive reaction for PCR detection targeting biosynthetic gene clusters of PKS (Type-I polyketide synthase) and NRPS (Non-ribosomal polypeptide synthetase) genes. Major metabolite from the BK185 was analyzed by The LC/MS and identified to geldamycin, which was known to contained broad antibacterial, antifungal or anticancer activities. The results provide evidences that the strain, BK185 can be promising biocontrol agent for ginseng organic farming.

• The Korean Journal of Mycology
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• v.14 no.2
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• pp.109-119
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• 1986

The correlations between environmental influences on microorganisms in soil and its effects on disease development in ginseng field were studied to obtain some useful data for increasing ginseng production and effective preventive measures against the root rot caused by soil-borne pathogens. The diseased replanted ginseng fields were selected as the diseased field and the healthy plot in first planted field selected as control in three major Korean ginseng producing areas such as Kumsan, Goesan and Poonggi. The physicochemical characteristics of the soil were analyzed and microorganisms susceptible for root rot of ginseng, such as Fusarium spp. and general fungi were investigated for their population density in various soil conditions. Correlations between soil microbial populations and environmental factors were investigated. The numbers of Fusarium spp. propagules were abundant in fall in both soil conditions. The numbers of Fusarium spp. were 1.9 to 2.6 times higher in replanted field than first planted field except Goesan area. Relative ratio of Fusarium spp. to total fungi propagules in replanted field was 1.6 times higher in replanted field than first planted field indicating higher numbers of Fusarium spp. distributed in replanted field of soil. The numbers of propagules of total fungi were increased in June and July and there was no sensitive variation according to the temperature. There was no significant difference in vertical distributions of total fungi according to soil depth, while the total fungi were abundant in the surface layer and $10{\sim}15\;cm$ layer. The contents of organic matter and phosphate in healthy field were somewhat high, and phosphate/organic matter ratio and Mg contents were high in diseased field. All of the soils showed a weak acidic pH of 4.5 to 5.7. Soil moisture contents were increased during winter season, but did not show any significant changes during the growing periods, showing 24.6% in healthy field and 19.5% in diseased field respectively. Soil temperature was the highest in July and August and the lowest in January and February.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2005.11a
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• pp.183-183
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• 2005

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.184-193
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• 1986

Interrelation between environmental influences on soil microorganisms and it's effect on disease development in ginseng (Panax ginseng C.A. Meyer) field were studied to obtain a preventive measures against the root rot of ginseng caused by soil-borne pathogens in soil in three major Korean ginseng producing areas such as Kumsan, Goesan and Poonggi. Populations of actinomycetes were relatively high in fall season from September to November. Their numbers were highly populated in healthy plot in field than replanted disease field of ginseng, whereas ratio of Trichoderma spp to actinomycetes increased in healthy plot of field indicating the higher numbers of Trichoderma spp pressented in healthy plot field. The numbers of propagules of Trichoderma spp generally increased in early summer through early fall season. Their numbers were also highly populated in the healthy plot of fields. The contents of organic matter and phosphate in healthy plot of field were somewhat high, and phophate/organic matter ratio and Mg content were high in diseased replanted field. All of the soil samples showed a weak acidic pH from 4.5 to 4.7. Soilmoisture content was increased during winter season and it did not show any significant changes curing the growing period, showing 24.6% in healthy plot in field and 19.5% in deseased plot in field respectively. Soil temperature was highest in July and August and lowest in January and February.