• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.268-277
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• 1998

The production of Korean ginseng, one of the most important medicinal root crops, is limited by many factors including soil sickness, root rots in fields as well as during storage prior to consumption. Although much research has been conducted on the diseases in field condition, little information is available on the control of postharvest roots rots. To obtain better management strategy of postharvest root rots in ginseng, biological control using antagonistic bacteria was attempted. Of 208 bacteria obtained form suppressive soil samples, 4 were selected based on the inhibitory effect on mycelial growth of two major causal fungi for postharvest root rots in ginseng, Botrytis cinerea and Fusarium solani. The culture filtrates of these bacterial antagonists greatly inhibited the conidial germination of both pathogenic fungi and produced abnormal morphology such as swollen germ tubes in F. solani and vacuolation of nongerminated conidia in B. cinerea. The population levels of bacterial antagonists on the ginseng roots were gradually increased up to 8 days of incubation. Postharvest root rots of ginseng caused by f. solani and B. cinerea were controlled in dipping tests in the ranges of 60∼80% by antagonistic Bacillus spp. obtained from suppressive soil. These results suggest that biological control using these antagonistic bacteria would be an alternative strategy to control postharvest root rots in ginseng.

• Proceedings of the Ginseng society Conference
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• 1978.09a
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• pp.67-74
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• 1978

The phenomenon of 'soil sickness' is one of the most important limiting factors for ginseng(Panax ginseng) production in Korea. The principal cause is known to be due to the root rots caused by Cylindrocarpon destructans and Fusarium solani. Attempts were made to control the root rots with non-polluting cultural methods or soil amendments. Among the nine soil amendments tested, crab shell, cow bone and pig feces were selected for further testing. Each of the three amendments increased the populations or various actinomycetes in the range of 10-25 times over that of non-amended soil, whereas the population of C. destructans was reduced to about $50-70\%$ as compared with the control. Five isolates of Streptomyces with clear zones on chitin-agar medium were selected and then tested for their antagonistic effects on C. destructans. When anyone of the five isolates of Streptomyces and C. destructans was grown together in a modified peptone broth, growth of the latter was highly inhibited. When three levels of crab shell, cow bone, or pig feces were used to amend potted soil infested with C. destruetans, the root rot ratings of ginseng seedlings were reduced to less than one half in all the treatments as compared to the control. In another similar experiment, crab shell and cow bone amendments resulted in almost complete control of the seedling root rots in soil infested with C. destructans or F. solani. In conclusion, biological control with soil amendments of ginseng root rots caused by C. destructans and F. solani was successful. Further basic studies should be pursued using soil amendments for better control. In addition, field experiments are needed to complement the soil amendment control measures in an integrated pest control program.

• Journal of Ginseng Research
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• v.26 no.3
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• pp.151-158
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• 2002

Ginseng (Panax quinquefolius L.) has become one of the most valuable herb crops grown in North America. However, traditional cropping practices are favourable to disease and significant losses due to root disease are common, despite frequent use of fungicides. Seedlots are often contaminated with pathogens, however, little is known about the causes of seed decay and the role of seed pathogens as incitants of root rots. It was shown that both Fusarium spp. and Cylindrocarpon destructans were able to rot seeds and that C. destructans was more virulent than Fusarium spp. on seedling roots. A modified rose bengal agar MRBA) medium (1 g KH$_2$PO$_4$; 0.5 g MgSO$_4$; 50 mg rose bengal; 10 g dextrose; 5 g Bacto peptone; 15 g Bacto agar; 30 mg streptomycin sulfate; 250 mg ampicillin; 10 mg rifampicin; 500mg pentachloronitrobenzene; 500 mg dicloran; and 1 L distilled water) was superior to potato dextrose agar in detecting C. destuctans in diseased roots. Isolation of C. destructans from diseased seedlings arising from seeds sown in replant soil supported the hypothesis that this pathogen is a cause of ginseng replant failure in North America.

• The Korean Journal of Mycology
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• v.19 no.1
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• pp.66-73
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• 1991

Among 110 isolates of actinomycetes isolated from ginseng pathogen-suppressive soils, the three actinomycetes showing the effective controls to Fusarium solani or Cylindrocarpon destruc­tans causing ginseng root rots were identified according to their morphological, cultural and physio­logical characteristics on various culture media. Spore chains of K 6-2, S 2-1 and Y 2-2 were Spira (S), Retinaculum-apertum (RA) and Rectus-flexibilis (RF), respectively. Spore surfaces of K 6-2 were spiny, whereas S 2-1 and Y 2-2 were all smooth. Aerial mass colors of 3 isolates were gray series. As a result of various tests, they were identified as Streptomyces variabilis, Streptomyces virgi­niae and Streptomyces griseo/us, respectively.

• International Journal of Industrial Entomology and Biomaterials
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• v.39 no.2
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• pp.82-85
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• 2019

We investigated the anti-microbial activity of propolis against the pathogenic bacteria and fungi on ginseng. We selected six microbials that caused postharvest root rots in ginseng. Propolis extracts were prepared by using the ethanol extraction method. We seeded the bacteria and fungi related to ginseng disease on a specific culture medium, and treated it with propolis extracts by using the paper disc method. Propolis extracts indicate the anti-microbial activity against Paenibacillus polymyxa, Fusarium solani, Rhizoctonia solani AG-1 and Pythium ultimum. However, the anti-fungal activity of propolis is weak on Pseudomonas fluorescens subsp. Cellulosa and Colletotrichum gloeosporioides. As a result, the antimicrobial effects of propolis against microbial that prevent ginseng growth were confirmed. The antimicrobial effects are shown according to the concentration of propolis against root rot. The fungi also showed antibacterial effects in a dose-dependent manner.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.103-108
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• 1998

The Canadian production of American ginseng (Panax quinquefolius L.) occurs mainly in Ontario, British Columbia and the Atlantic provinces. Although ginseng is a profitable crop, its successful production is dependent on careful consideration of cultural management f include site selection, site preparation, seed selection and handling, shading actors which and mulching, pest and nutritional management, and handling of harvested crops. Diseases of particular concern in Atlantic Canada are root rots caused by Phytopkthora cactorum, Cylindrocarpon destructans and Fusarium sp. Recently two systemic fungicides (metalaxyl and fosetylal) were registered; however, growers in Atlantic Canada have experienced metalaxyl resistance resulting from the reliance on this single compound for the control of Phytophthora sap. Current research being conducted on alternative control of these diseases will be discussed. In weed control research, 2, 4-D, MCPA, clopyralid have continued to show promise for weed contro1 at low rates. In trials to evaluate non-selective herbicides as post-senescence or pre-emergence in ginseng, glyphosate (Round-up) provided control of perennials as well as willowherb and lambsquarters. In phytoxicity trials, ginseng significantly tolerated grass herbicides, including clethodim, rimsulfuron, trakloxydim, nicosulfuron and fenoxyprop. For broadleaf herbicides, significant tolerance was shown for bromoxynil, thifensulfuron methyl, flumetulam/clopyralid, thifensulfuro/tribenuron. Disease and weed management of ginseng in Atlantic Canada will be discussed.

• Research in Plant Disease
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• v.24 no.4
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• pp.332-338
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• 2018

In August of 2011, a wilting disease of ginseng was observed at Bongwha, Gyeongbuk province, Korea. Affected plants initially show withering symptoms on leaves of ginseng. As the disease progresses, withering leaves spread downward, eventually encompassing the whole plant. Leaves lose vigor but remain pale green. Symptoms of roots were brown, and soft rots characterized by moist and watery decay of the whole ginseng root, which initiated as small brown, water-soaked lesions of hairy roots and enlarged to the entire roots. The causal organism isolated from the infected roots was identified as Serratia plymuthica based on its physiological and biochemical characteristics, by cellular fatty acid composition (GC-FAME), the utilization of carbon sources (BioLog System), and 16S rRNA sequence of the isolated bacterium were 99% homologous to those of Serratia plymuthica strains. Artificial inoculation of the bacterium produced the same brown or soft rot symptoms on the ginseng roots, from which the same bacterium was isolated. This is the first report of bacterial root rot caused by the Serratia plymuthica in ginseng in Korea. Serratia plymuthica has been used as antagonistic microorganism for biological control on several crop plants. But it was proved pathogen of ginseng at humid condition in this study.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1994.06a
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• pp.1-10
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• 1994

Biological control of plant disease has been considered a potential control strategy in integrated pest management in recent years. This paper reviewed the progress of research on the biological control of plant diseases in Korea during the last two decades and adopts some future prospects. The crop diseases included, red pepper, Phytophthora blight, ginseng root rots cucumber wilt, sesame damping-off, strawberry wilt and tobacco bacterial wilt and mosaic. Biological control of plant diseases requires a multi-disciplinary approach involving input from plant pathologists, ecologists, mycologists and molecular biologists. The author proposed to organize a group“Committee for Biological Control”including researchers, industries, growers and administrators.

• The Korean Journal of Mycology
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• v.18 no.3
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• pp.164-177
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• 1990

This study was carried out to obtain some useful data for increasing an effective ginseng production. There was a direct relationship (r=0.2645) between spore germination of Fusarium solani and soil pH, and (r=0.315) between Cylindrocarpon destructans and soil pH. On the other hand, there was a direct relationship (r=0.19) between relative hyphal growth of Rhizoctonia solani and soil pH. There was a direct relationship (r=0.21) between number of total bacteria and F. solani, (r=0.37) between actinomycetes and F. solani and (r=0.20) between celluloytic bacteria and F. solani. However, there was an inverse relationship (r=-0.20) between number of total fungi and F. solani. There was a direct relationship (r=0.24) between number of actinomycetes and R. solani. Each ginseng pathogen-suppressive soil screened was 40 in F. solani, 20 in C. destructans and 9 soil samples in R. solani among 146 soil samples, respectively. The mean contents of K, Ca and Mg were fairly lower in each ginseng pathogen-suppressive soil than conducive soil, whereas Na were somewhat lower. The mean contents of organic matter were over 2 times higher in each ginseng pathogen-suppressive soil than conducive soil. The mean contents of phosphate were fairly lower in F. solani and R. solani-suppressive soil than conducive soil and, on the other hand, were somewhat higher in C. destructans-suppressive soil than conducive soil. The mean soil pH was somewhat lower in each ginseng pathogen-suppressive soil than conducive soil. The mean contents of sand were about 2 times higher in each ginseng pathogen­suppressive soil than conducive soil, whereas silt and clay were somewhat lower. The microbial numbers of total bacteria, total fungi and celluloytic fungi were higher in F. solani-suppressive soil than conducive soil, whereas actinomycetes and celluloytic bacteria were lower. Each microbial number of total bacteria or total fungi indicated a significant difference (p=0.05) between F. solani­suppressive and conducive soil, and the microbial number of actinomycetes was a highly significant difference (p=0.01) between F. solani-suppressive and conducive soil. The microbial numbers of total bacteria, total fungi, actinomycetes and celluloytic fungi were higher in C. destructans-suppressive soil than conducive soil, whereas celluloytic bacteria were about 2 times lower. On the other hand, the microbial numbers of total fungi were higher in R. solani-suppressive soil than conducive soil, whereas total bacteria, actinomycetes, celluloytic bacteria and celluloytic fungi were lower. Fourteen of 16 F. solani-suppressive soils tested were suppressive to ginseng root rot, whereas fifteen of 16 C. destructans-suppressive soils were suppressive. Ginseng root rots of ginseng disease-suppressive soils were in the range of 1.0-17.4% in F. solani-suppressive soil and 0.2-20.4% in C. destructans-suppressive soil, respectively.