• Research in Plant Disease
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• v.13 no.3
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• pp.164-169
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• 2007

Three kinds of disease occurring on ginseng leaves, such as grey mold, Alternaria blight, and anthracnose, started at the beginning of June, July, and August, respectively. The disease incidence was rapidly increased from the beginning of rainy season. To develop the control system with fungicides, 6 fungicides were selected and applied on ginseng at the indicated time. Calculating the control value by using the area under the disease progressing curve (AUDPC), the control activities of the supervised control system with fungicides were 61.7, 78.8 and 70.5% against grey mold, Alternaria blight, and anthracnose, respectively. The application of the mixture of carbendazim and diethofencarb on first of June was very important in control system with fungicides. If it was deleted in control system, control value was decreased against grey mold. In the case of Alternaria blight and anthracnose, the application of difenoconazole on July 18, and trifloxystrobin on August 7 were indispensible. If difenoconazole and trifloxystrobin were not applied on July 18, and August 7, the control activities against Alternaria blight and anthracnose, respectively, were decreased to 28.9% and 44.4%.

• Journal of Mushroom
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• v.16 no.3
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• pp.170-174
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• 2018

This study aims to investigate the antifungal and protective effects of water- and 70% methyl alcohol-extracts from spent mushroom substrate (WESMS and MeOHSMS) of Lentinula edodes, on Botrytis cinerea- the causative agent for gray mold disease in ginseng. MeOHSMS inhibited mycelial growth and spore germination of Botrytis cinerea, by 75% and 95%, respectively. MeOHSMS could suppress gray mold disease of ginseng seedlings by 80% and effectively reduce the disease severity by 60%. Compared to the treatment of ginseng leaves with WESMS and DL-${\beta}$-aminobutyric acid (BABA), the MeOHSMS treatment increased the phenolic compounds in the leaves by 36% and 18%, respectively. These results suggest that the SMS extracts suppress gray mold disease in ginseng via dual functions: antifungal activity and increase in a plant defense factor-phenolic compounds.

• Research in Plant Disease
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• v.13 no.3
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• pp.177-182
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• 2007

In this experiment, 236 isolates of Botrytis cinerea isolated from the lesions of ginseng grey mold in 2005 and 2006 were examined for their sensitivity to fungicide inhibiting ${\beta}-tubulin$ assembly. The baselines of fungicide resistance were determined as 10.0 and $0.2{\mu}g/ml$ of $EC_{50}$ values for carbendazim and the mixture of carbendazim and diethofencarb, respectively. The ratios of isolates resistant to carbendazim in 2005 and 2006 was investigated to be 87.6 and 96.6%, respectively. In the case of the mixture of carbendazim and diethofencarb, the ratio of the resistant isolates was 23.6% for 2005 and 24.5% for 2006. The ratio of the resistant isolates to the mixed fungicide was fluctuated according to regions where isolates of B. cinerea were obtained. In Yeoncheon of Gyeonggi Province, 4.3% of the isolates used in the experiment was resistant in 2005 and no resistant isolate was obtained in 2006. Among 5 regions, the ratio of resistant isolates was the highest as 70.0% in Yecheon of Gyeongbuk Province.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.583-589
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• 2012

In the continued research on natural fungicides for the control of plant diseases by using plant-derived products, we found that Reynoutria elliptica. had a strong fungicidal activity against several plant pathogens. R. elliptica (3.2 kg) were extracted with 80% aq. MeOH and the concentrated extracted was partitioned with n-hexane, EtOAc, n-BuOH and $H_2O$ successively. The four layers were tested their disease control efficacies against 4 plant disease such as rise blast (RCB), tomato grey mold (TGM), tomato late blight (TLB), and barly powdery mildew (BPM). The n-hexane fraction was highly active showing over 95% control against TLB and BPM. and the EtOAc fraction was highly active showing over 95% control against RCB, TLB, and BPM. By using silica gel chromatography, MPLC, and HPLC, three compounds that were expected to have antifungal activity were isolated. Their chemical structures were elucidated as physcion, emodin, and emodie-8-O-glucoside by EI-MS and NMR spectroscopic analyses.

• Research in Plant Disease
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• v.27 no.2
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• pp.66-69
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• 2021

In 2020, a brown felt was observed on persimmon (Diospyros kaki) in persimmon orchards, Sangju, Korea. The symptom on persimmon was white to grey mycelial mats on some areas of the branches. Each mat progressively expanded until the mats coalesced to occupy larger areas and finally girdled the branches. The disease branches were covered with brown-colored mold, consisting of hyphal mats of the pathogen. Optimum temperature for mycelial growth was 30℃. On the basis of mycological characteristics, pathogenicity test, and molecular analysis with complete internal transcribed spacer rDNA region, the causal fungus was identified as Septobasidium sp. This is the first report of brown felt caused by Septobasidium sp. on persimmon in Korea.

• Korean Journal of Medicinal Crop Science
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• v.7 no.4
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• pp.308-313
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• 1999

Direct seeding is a cultivation method of Korean ginseng which can cut down production cost and increase productivity. This study was conducted to obtain detailed information about this method and to aid the development of it in Korea. Major pre-crops before ginseng cultivation were rice, corn and rye, and organic matters, such as rice straw, rye straw and poultry feces were used for basal fertilization. In direct seeding of the ginseng field, seeding density was 196 to 210 seeds per $3.3m^2$ and germination ratio was 67%. Survival ratio of 4-year-old ginsengs which were products of direct seeding was 51%, and more than 100 plants per $3.3m^2$ survived. The most critical diseases in the directly seeded ginseng field were grey mold, damping off, and stem diseases including stem spot disease. Plant growth of the ginseng cultivated by the direct seeding method was not different from the ginseng cultivated by transplanting method. But the root of the ginseng cultivated by the direct seeding method took the shape of a shorter main root compared to the ginseng cultivated by the transplanting method. Root yield per $3.3m^2$ of the direct seeding ginseng field was larger compared to the field of the transplanting cultivation.

• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.209-216
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• 2012

In the continued research on natural fungicides for control of plant diseases by using plant-derived products, we found that Spatholobus suberectus Dunn had a strong fungicidal activity against several plant pathogens. S. suberectus (1 kg) was extracted with 80% aqueous MeOH and then the concentrated extract was partitioned with n-hexane, EtOAc, n-BuOH and $H_2O$ successively. The four layers were tested their disease contron efficacies against 6 plant diseases such as rice blast (RCB), rice sheath blight (RSB), tomato grey mold (TGM), tomato late blight (TLB), wheat leaf rust (WLR), and barley powdery mildew (BPM). The EtOAc fraction was highly active showing over 80% control against RCB, TGM, TLB, and BPM. By using silica gel chromatography, preparative TLC and HPLC, six compounds that were expected to have antifungal activity were separated. Their chemical structures were identified as ethanone, hydroxytyrosol, epicatechin, procyanidin B2, dimethoxy daizein and formononetin by ESI-MS, $^1H$-NMR, $^{13}C$-NMR, and 2D-NMR spectroscopic analyses. The chemicals except epicatechin were first reported in S. suberectus. Study on in vitro and in vivo antifungal activities of the isolated compounds is in progress.