• Research in Plant Disease
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• v.19 no.3
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• pp.208-215
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• 2013

3-(4-Hydroxyphenyl)-propionic acid (HPP) is a bacterial metabolite synthesized and released by an entomopathogenic bacterium Xenorhabdus nematophila K1. In this study, the control efficacy of HPP was tested against Phytophthora blight and anthracnose of red pepper plants. HPP suppressed mycelial growth of Phytophthora blight and anthracnose pathogens. Under natural sunlight condition, HPP maintained the antifungal activity on the diseases for at least twenty five days. The antifungal activity was not decreased even in the condition of soil-water. It was proved that HPP was able to penetrate the roots and travel upward of the red pepper plants. When HPP suspension was applied to soil rhizosphere before transplanting the red pepper seedlings or was regularly sprayed to the foliage of the plants with ten days interval, it resulted in significant reduction of the disease occurrences (Phytophthora blight and anthracnose) without any phytotoxicity. These results suggested that HPP can be developed to a systemic agrochemical against Phytophthora blight and anthracnose of red pepper plants.

• Korean Journal of Organic Agriculture
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• v.28 no.4
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• pp.579-589
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• 2020

This study was carried out to evaluate the effect of rye as green manure crop on the improvement of soil environment and reduction of Phytophthora blight in red pepper of open field where Phytophthora blight occurred frequently. Soil physical properties such as bulk density and porosity were increased in rye cultivation. In addition, gaseous was increased but liquid was decreased compared with conventional cultivation. The analysis of phospholipid fatty acids extracted from soil showed that rye cultivation significantly increased relative abundance of microbial community and ratio of aerobic to anaerobic bacteria. Furthermore, ratio of saturated to unsaturated fatty acids and cyclo-fatty acids to precursor. the indicators of increasing in environmental stresses, were reduced in rye cultivated field. Occurrence of Phytophthora blight in rye cultivation was reduced 30.7% compared with conventional cultivation. These results suggest that rye cultivation in red pepper of open field where Phytophthora blight occurred can improve soil environment and reduce damage of Phytophthora blight.

• The Plant Pathology Journal
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• v.17 no.5
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• pp.249-256
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• 2001

Xanthomonas axonopodis pv. glycines 8ra produces a bacteriocin called glycinecinA, which specifically inhibits the growth of bacteria belonging to Xanthomonas species. GlycinecinA was produced by culturing Escherichia coli DH5 containing biosynthetic genes for glycinecinA, and was tested for its control effect against X. vesicatoria on red pepper and X. oryzae pv. oryzae on rice. The bacteriocin activity was much higher in the cell extract than in the supernatant. It reached a maximum level at the stationary phase, ws maintained up to 2 months at room temperature and approximately 10 months at $4^{\circ}$. The optimum concentration of glycinecinA for the control in the greenhouse and in the field was 12,800 AU/ml. In this study, the activity of glycinecinA on rice and red pepper leaves continued for 7-8 days, during which the pathogen populations remained at low levels. Bacterial leaf spot of red pepper and bacterial leaf blight of rice were significantly reduced by the bacteriocin treatments. The control efficacy was as high as, or even higher than, the chemical treatment of copper hydroxide. These results suggest that the bacteriocin is a potential control agent for bacterial diseases.

• Research in Plant Disease
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• v.16 no.1
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• pp.106-108
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• 2010

This survey was conducted to investigate effect of covering with polyvinyl ($120{\times}90cm$) on incidence of Phytophthora blight and anthracnose and growth. Early growth of pepper plant was superior when was covered with polyvinyl after planting. Incidence of anthracnose and Phytophthora blight was lower 26.9% and 60.3% in covering system than those in conventional culture system, respectively. A yield of dried red pepper was more 48.5% in cultured with covering system than that in conventional culture system.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.16-21
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• 2001

Regression models were obtained on the base of the correlation between Phytophthora blight incidence in red pepper and the microclimate data obtained from automated weather station (AWS) during 1997 and 1998. A computer program (PEPBLIGHT) was constructed based on the model that the R2 value is highest among regression models. This computer program uses the microclimate data from more than one AWS through the common dialogue box easy and it is able provide disease forecasting information. In addition, it could be applied far other diseases and converts the microclimate data of AWS to the input data for Statical Analysis System (SAS). PEPBLIGHT was first developed for the forecasting computer system of red pepper blight in Korea. PEPBLIGHT is operated on the MS Windows, so that it is easy to use.

• Research in Plant Disease
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• v.18 no.1
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• pp.17-23
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• 2012

Indole compound is a bacterial metabolite synthesized and released by an entomopathogenic bacterium, Xenorhabdus nematophila K1. The antibiotic activity was evaluated against plant pathogens, such as Phytophthora blight and anthracnose of red pepper. Indole significantly suppressed mycelial growth of Phytophthora blight and anthracnose pathogens. Under natural sunlight conditions, indole maintained the antifungal activity for at least sixty days. The activity was not affected under the condition of soil-water. When the indole suspension was applied to surface soil before transplanting of red pepper seedlings and was then regularly sprayed to the foliage of the plants with ten days interval, it resulted in significant reduction of the disease occurrences (Phytophthora blight, anthracnose, soft rot, and black mold) by about 30%. These results suggest that indole can be used to control Phytophthora blight and anthracnose of red pepper.

• Journal of Ginseng Research
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• v.14 no.1
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• pp.36-43
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• 1990

The quality of raw, red and white ginseng and the contents of some minerals were examined using 6-year-old ginseng roots produced in different shades, thatch and polyethylene net (P..E.). The yield of first and second grade ginseng roots was higher in the thatch shade than in the P.E. shade. The smaller sizes of ginseng routs were probably due to loss of ginseng yield called by alternaria blight in the third and fourth years, and lower quality was dale to more rusty roots in the P.E. shading. For red ginseng. rates of heaven and earth grades were higher in the P.E. than thatch shade. producing red ginseng with less inside cavity Production of white ginseng was higher in the thatch shade than in the P.E. shade. showing a higher yield, better piece grade, lower inside crack and better quality index in the thatch. The contents of some minerals such as K, Ca, Mg and Mn of fine ginseng roots differed between the two shades, some of which had a significant correlation with the quality indices of white ginseng. Keywords Thatch shade, polyethylene shade, alternaria blight, rulsty root, quality of ginseng.

• Korean journal of applied entomology
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• v.1
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• pp.37-41
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• 1962

Fifty three varieties of potatoes were planted at Alpine Potato Research station at Takwalyong Kangwando Province since in 1962. The varieties planted were introduced front Japan, the United States and Germany. The varietal reaction was divided into five classes, and the results were following. Immune : Kennebec, Isola, Cherokee, Merrimack, Yoraku, Lisili. Cosima. Highly Resistant : Antze, Ragis Isola, Hessenkrone, Plymouth, Sebago, Pungo, Sieglinde, Anco, Essex. Resistant : Tawa, B-605-10, Sequoia, Grata, Concordia, Onaway, Holing 1. Nisego. Susceptible: Nordak, Pontiac, Benimaru, Early Gem, Chippewa, Chitose, Ohjiro, Red Bake, Norland, Katahdin. Highly Susceptible: Russet Burbunk, May Queen, Earlaine, Irish Cobbler, Feldeslohn, Red Warba, Chisago, Osseo, Paunee. Warba, Norgleam, Red Beauty, Red Burt, Danshaku, Namchak (Native variety), In general the verieties introduced from the United States and Germany were more resistant to late blight than those introduced from Japan. Especially the German varieties were immune or highly resistant to the disease except Feldeslohn. Early maturing varieties were more susceptible to late blight than the late maturing varieties in southern Korea.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.724-732
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• 2020

Phytophthora capsici is the organism that causes Phytophthora blight which infects red pepper plants prolifically, ultimately leading to crop loss. A previous study revealed that Enterobacter asburiae ObRS-5 suppresses Phytophthora blight in both red pepper and Ligularia fischeri plants. In order to determine whether the induced systemic resistance (ISR) was triggered by pre-infection with the ObRS-5 strain, we conducted quantitative PCR using primers for PR1, PR4, and PR10, which correlate with systemic resistance in red-pepper plants. In our results, red pepper plants treated with the ObRS-5 strain demonstrated increased expression of all three systemic resistance genes when compared to controls in the glasshouse seedling assay. In addition, treatment of red peppers with the ObRS-5 strain led to reduced Phytophthora blight symptoms caused by P. capsici, whereas all control seedlings were severely affected. Perhaps most importantly, E. asburiae ObRS-5 was shown to induce the ISR response in red peppers without inhibiting growth. These results support that the defense mechanisms are triggered by ObRS-5 strain prior to infection by P. capsici and ObRS-5 strain-mediated ISR action are linked events for protection to Phytophthora blight.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.64-70
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• 2000

Control effects of phosphorous acid were investigated on three diseases. For Phytophthora blight of red pepper, protective and curative effects of phosphorous acid at the concentration of $1,408{\mu}g$ a. i./mL were 91.0% and 80.0%, respectively. In case of late blight of tomato, caused by Phytophthora infestans, protective and curative effects were 63.4% and 13.0% at the same concentration, respectively. However, the protective and curative effects of phosphorous acid increased by decreasing inoculum density of Phytophthora infestans. The protective effects of phosphorous acid on control of Phytophthora blight of red pepper was persisted for 4 days with high control efficacy (94.0%). The protective and curative effects of phosphorous acid ($1,408{\mu}g$ a. i./mL) on cucumber downy mildew were 82.0% and 62.0% respectively. The foliar application of phosphorous acid also promoted shoot growth and fresh weight of red pepper.