• The Korean Journal of Mycology
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• v.44 no.4
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• pp.330-337
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• 2016

Streptomyces sp. A75 and A501 inhibited the mycelial growth of pathogenic Rhizoctonia solani and Pythium sp., which cause the ginseng disease known as damping-off. Three methods were evaluated for the control of these pathogens, using a mixture of the culture broths from Streptomyces sp. A75 and A501. The methods tested were seed dipping with 50-fold diluted broth, drenching of soil with 100-fold diluted broth after sowing, and combined seed dipping and drenching. These methods reduced the incidence of ginseng damping-off caused by R. solani by 81.3%, 84.8%, and 32.2% and that caused by Pythium sp. by 51.0%, 52.1%, and 75.3%, respectively. Based on these results, the combination of seed dipping and soil drenching after sowing using a mixture of the culture broths from Streptomyces sp. A75 and A501 effectively reduced the incidence of damping-off in ginseng.

• 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.

• Korean Journal of Pharmacognosy
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• v.3 no.2
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• pp.73-79
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• 1972

Losses, literature and occurence of ginseng diseases in Korea were reviewed briefly. Some problems on etiology, epidemiology and control measures of root rot caused by Cylindroaroon panacis, anthracnose, and damping-off have been discussed. Ginseng was added as a new host of $Sclerotium\;rolfsii\;S_{ACC}$.

• 한국약용작물학회:학술대회논문집
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• 2007.05a
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• pp.127-128
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• 2007

• 한국약용작물학회:학술대회논문집
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• 2007.05a
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• pp.125-126
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• 2007

• Journal of Ginseng Research
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• v.5 no.1
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• pp.73-84
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• 1981

Effect of environmental factors and host on the growth and outbreak of various ginseng diseases was reviewed Environmental lectors included hydrogen ion concentration, moisture content, temperature, nutrition, and microbiol populations. Age of the ginseng plants in relation to several ginseng disease occurrence was also included in order to formulate the effective control measure for ginseng diseases. Damping-off caused by Rhizoctonia, Pythium, and Phytophthora, greymold by Botrytis, sclerotinia by Scleretinia, and phytophthora blight caused by Phytophthora were usually prevalent during the early growing season of ginseng when temperature is below 20$^{\circ}C$, while anthrac se caused by Colletotrichum, alternaria blight by Alternaria, and bacterial soft rot by Erwinia were so during the latter growing season when temperature is above 25$^{\circ}C$. However, the root rot incited by Fnarium and Cylindrocarpon caused severe damages throughout the growing season. Growth range of the temperature for a pathogen was highly related to the corresponding disease outbreak. Hydrogen ion concentration was highly related to the outbreak of sclerotinia, root rot, and red rot. Most severe outbreak of those diseases where the soil acidity was pH 4.7, pH 6.5- 7.5, and pH6.0-6.5, respectively. Nitrogen content in the soil was also related to outbreak of root rot and red rot. More red rot occurred where NH,-nitrogen is above 30 ppm and more root rot obtained when excessive nitrogen fertilizer applied. Yellow necrosis apparently was related to magnesium especially its ratio with potassium or calcium content in a soil. Fusarium Population showed significant .relations to missing rate of ginseng Plants in a Implanting ginseng field, while that of total bacteria showed similar relations in all ginseng field, However, in six year old ginseng fields, the more the Streptomyces population was, the less the Fusarium obtained. Consequently, less missing rate observed in a field where Streptomyces population was high. Damping-off, root rot, Rhytophthor a blight were mose severe on the nursery and on 2-3 years old ginseng plants, whereas sclerotinia, and grey cod, alteraria blight, anthracnose were severe on 4-6 years old ginseng plants. Root rot caused by Fusarium and Erwinia, however, was also severe regardless of the age of the plants when the roots were injured. Therefore, for the effective control of ginseng root rot most careful control of the disease during the early year should be rendered.

• Journal of Ginseng Research
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• v.28 no.4
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• pp.183-190
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• 2004

On May of 2002, the 34 isolates of Rhizoctonia solani were isolated from the symptom of damping-off on basal stems of 2-year-old to 6-year-old Panax ginseng which were cultivated in the 17 fields in Kyunggi-do, Chun­gcheungnam-do and Jeollabuk-do province in Korea. All isolates were identified as anastomosis group 2-1. Pre-emer­gence damping-off occurred on underground part of stem of 2-year-old ginseng in the pot trial with artificial inoculation. However, in the 4-year-old ginseng field with artificial inoculation, post-emergence damping-off occurred. The severe incidence of damping-off was found in the 6-year-old ginseng field in Kimje-si, Jeollabuk-do province on June 5 of 2003, the rate of which showed $18.6{\%}$ of area in the field by spread of the disease since 2-year-old. The sclerotia of R. solani, started to be formed after 7 days incubation on potato dextrose agar at $25^{\circ}C,$ were grayish brown, spherical to irregular and about $500{\mu}m$ in diameter, which became dark brown after 14 days incubation. The temperature range for the myce­lial growth of R. solani isolates was $5\~30^{\circ}C,$ and the optimal temperature was $25^{\circ}C,$ their growth were very poor at $5\;or\;30^{\circ}C$. The isolates grew at the range of pH $4.5\~8.1$ tested and optimal pH for growth was pH 4.5$\~5.8%, whereas their growth were very poor above the pH 7.2.

• Korean Journal of Medicinal Crop Science
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• v.26 no.5
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• pp.401-407
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• 2018

Background: In Korea, seeds of Panax ginseng C. A. Meyer need to be stored under cold temperature and high humidity condition for months to break physiological dormancy, making storage difficult until spring-sowing. This study was conducted to test the effects of seed storage conditions and seed treatment on the emergence of seedling after spring-sowing in a nursery greenhouse. Methods and Results: After dehiscence, endocarp dried seeds in mild or completely, and wet seeds were stored in $2^{\circ}C$ and $-3.5^{\circ}C$ during winter. Storage at $-3.5^{\circ}C$ resulted in a lower emergence rate (ER) than that at $2^{\circ}C$, and additional cold ($2^{\circ}C$) treatment before or after storage at $-3.5^{\circ}C$ increased the ER. Endocarp dehydration prevented pre-germination at $2^{\circ}C$ storage and increased the ER of seeds stored at $-3.5^{\circ}C$. ER was also dependent on the batch of seeds. However, seed treatments before sowing had only limited effects on ER. Root loss was the main reason for damping-off; prolonged cold storage of seeds increased damping-off, as the detection of pathogens was not high. Conclusions: This study showed that storage conditions such as temperature and moisture content of seeds, affect the ER after spring-sowing and vitality of seedlings, suggesting further attention on seed control for secure seedling stands after spring-sowing.

• Korean Journal Plant Pathology
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• v.10 no.4
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• pp.319-324
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• 1994

The monoxenic culture of the fungivorous nematode, Aphelenchus avenae, was applied for the control of soil-borne ginseng pathogens such as Fusarium solani and Rhizoctonia solani. Fungivorous nematode populations were measured in a field to examine relationships between the nematode populations and suppression of ginseng root diseases. Inoculation of A. avenae (5000 nematodes per petri-dish) reduced the colonization of the Fusarium mycelium on root discs of ginseng and carrot by 80.0% and 60.5%, respectively. A. avenae also significantly reduced the occurrence of damping-off of ginseng by R. solani pathogenic to ginseng, and no plant damage by the nematode was noted. In a 3-year-old ginseng field infested with Cylindrocarpon destructans, plant missing caused by root rot positively correlated to the density of potato rot nematode, Ditylenchus destructor, but it was reduced with the population of A. avenae, suggesting that A. avenae might inhibit the occurrence of ginseng root rot.

• Korean Journal of Medicinal Crop Science
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• v.22 no.5
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• pp.363-368
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• 2014

This study was conducted to find out the optimum composition of nursery soil for raising seedling of ginseng (Panax ginseng C. A. Meyer). Total 9 kinds of raw materials were used such as peat-moss, perlite, leaf mould, rice bran, gull's guano, castor-oil plant bark, palm bark, cow manure and chicken manure for optimum composition of nursery soil in ginseng. Occurrence of damping-off in ginseng was lowered about 50% in nursery soil type 1, 2 and 4 than in other types nursery soil in June, and occurrence rate of rusty root also lowest in nursery soil type 1. As the salinity of nursery soil increased, so did the occurrence of physiological disorder in ginseng seedling. The cause of salinity increasing in nursery soil has closely relation to $NO_3-N$, $P_2O_5$ and $Na^+$ content. Plant height, root length, diameter and weight were longer and heavier in nursery soil type 1 (mixing ratio of peat-moss, perlite and leaf mould was 50 : 20 : 30 based in volume) than in other types of nursery soil. So nursery soil type 1 was selected for raising seedling of ginseng. pH and electric conductivity (EC) of selected nursery soil type 1 was 5.55 and 0.13 dS/m. Contents of $NO_3-N$ and $P_2O_5$ were 21.0 and 40.0 mg/L, and $K^+$ 0.36, $Ca^{2+}$ 3.38, $Mg^{2+}$ 2.01 and $Na^+$ $0.09cmol^+/L$, respectively.