• Research in Plant Disease
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• v.24 no.2
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• pp.153-161
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• 2018

We selected eight resistant cultivars including 'Heukryongsamcheok', 'Heukgeumsolsamcheok' and 'Gangryeoksamcheok' showing high suppressive effect against cucumber downy mildew (CDM) through plastic film house and field trials in spring and autumn season in 2015. Of them, these three varieties, 'Heukryongsamcheok', 'Heukgeumsolsamcheok' and 'Gangryeoksamcheok' were used to evaluated suppressive effect against CDM by comparing disease severity (area under disease development progress curve, AUDPC) with those of three susceptible varieties under plastic film house condition. AUDPC of three resistant cultivars was in the range of 10.9 to 23.6, meanwhile those of three susceptible cultivars was in the range of 286.7 to 290.3. Consequently, we confirmed that cultivation of the selected resistant cultivars can reduce CDM in vivo. When disease severity (diseased leaf area) was investigated on a resistant cultivar ('Heukryongsamcheok') sprayed without any organic materials and susceptible cultivars sprayed single-, two times- and three times with Bordeaux mixture, sulfur-loess mixture and $Kocide^R$ (copper hydroxide), respectively, it was the lowest in the resistant cultivar plot compared to susceptible cultivar plots sprayed with any organic materials. In addition, we evaluated control effect of the selected resistant cultivar by comparing that of organic materials including lime sulfur mixture, Bordeaux mixture and garlic extract. As a result, Bordeaux mixture showed the highest control effect against CDM. AUDPC of Bordeaux mixture, resistant cultivar, lime sulfur, garlic extract and untreated control was 3.9, 10.6, 95.6, 24.9, and 258.7, respectively. Based on the above-mentioned results, we think that the resistant cultivars and Bordeaux mixture can be effectively used to control CDM as one of control measures under the farmhouse condition.

• Journal of Nutrition and Health
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• v.41 no.2
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• pp.141-146
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• 2008

Ixeris sonchifolia Hance (Godulbaegi), Oenanthe javanica (Dolminari), Fagopyrum esculentum Moench (Buckwheat>, Hizikia fusiforme (Seaweed Fusiforme) and Zingiber ojficinale Roscoe (Ginger) have been used respectively as one of folk remedies as well as food materials. However, reportedly few studies on their immunomodulating effects have been made, although it has been known from other preceding studies that the ex vivo supplementation of each Ish, OJ, Fem, Hf, Zor water extracts tends to enhance the proliferation of splenocyte in comparison to the control group. This study on the combined immunomodulative effect of water extract mixture of these five food materials (Ish + Oj + Fem +Hf+Zor) lasted covering seven or eight weeks. The old mice (balb/c) was fed ad libitum on chow diet, and the water extract of plant mixture was orally administrated every other day for four weeks at two different concentrations (50 and 500 mg/kg B.W) . After preparing the single cell suspension, the proliferation of splenocyte was determined by MTT (3-[4,5-dimethylthiazol-2-y]-2,5-diphenyl terazolium bromide) assay. The production of cytokine ($IL-{\beta}$, IL-6, and $TNF-{\alpha}$) which was secreted by macrophages stimulated with LPS or not was detected by ELISA assay using the cytokine kit. After the 48 hours of incubation with the mitogen (ConA or LPS) stimulation, the proliferation of the mice splenocyt in the experimental group statisticaly increased at both of two different concentrations in comparison to the control group. The cytokines production was more significantly enhanced at the lower supplementation (50 mg/kg B.W.) group than at the higher concentration (500 mg/kg B.W.). The result of this study may suggest that the supplementation of water extract of plant mixture can regulate and enhance the immune function by increasing the splenocyte proliferation and regulating the cytokine production capacity by the activated macrophages in mice.

• Korean Journal of Medicinal Crop Science
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• v.22 no.3
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• pp.231-236
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• 2014

This experiment was carried out to establish the optimum cutting time, plant growth regulator, and bed-soil for rooting by greenwood cutting of Schisandra chinensis. Approximately 7 cm long-shoots of greenwood cuttings were transplanted by various cutting times, plant growth regulators, and bed-soils in the plastic-film house. The rooting rate of greenwood cutting was 12.5% in the April 5th, 73.5% in the May 8th, and 75.5% in the August 5th. The number and length of primary root in greenwood cutting were more in the early May than those in the early August. For mass propagation of Schisandra chinensis. using greenwood cutting, shoots were treated with plant growth regulators on May to increase rooting rate. Rooting rate was 100% with IAA $50mg/{\ell}$, 92.9% with NAA $100mg/{\ell}$, and NAA $1,000mg/{\ell}$, for 60 min. To select effective media for rooting, various medias for bed-soil were treated by single and mixture form for 100 days after cutting. Rooting rate was 91.8% in the single treatment of peat moss or decomposition of granite soil, and this result was better than those in other treatment. The treatment by 1 : 1 mixture of peat moss and horticulture bed soil was rooting with 94.0% best rooting rate.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.41-45
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• 2004

A phosphate solubilizig bacterium, Pantoea agglomerans, was isolated from rhizosphere soils collected from Chungbuk area. A greenhouse experiment was conducted to study the effect of combined application of rock phosphate and P. agglomerans inoculation on plant growth and phosphate accumulation of rice (Oryza sativa L.). Apart from control that received no inputs, six treatments were planned as follows; 1) seed bacterization, 2) free cell inoculation and 3) bacteria immobilized beads inoculation, individually and in combination with 1 and 2.5 g of rock phosphate per pot. The results showed that plant growth and phosphate uptake were significantly enhanced as a result of bacterial inoculation. Bacterial inoculation in the form of immobilized beads and 1 g of rock phosphate was found to affect positively the rice plant growth and phosphorus accumulation than other treatments. The available phosphate concentration of the pot mixture also found improved as a result of P. agglomerans inoculation. A positive correlation was observed between the phosphate concentration in the pot mixture and phosphate accumulation in plant.

• Research in Plant Disease
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• v.20 no.3
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• pp.227-233
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• 2014

The mixture (MX) of acetic acid (AA) and lactic acid (LA) was examined for its effectiveness in the control of the pine wood nematode Bursaphelenchus xylophilus contaminated in cymbidium culture medium. Nematode mortality in vitro was nearly 100% in AA and MX at the concentrations of 5.0-1.0% (pH 2.6 - 4.2) and in LA only at 5.0% (pH 3.5), but lowered at concentrations of 0.5-0.1% (pH 5.1-6.9) more significantly in LA than AA and MX. MX of most concentrations caused higher nematode mortality than the average response to AA and LA. All treatments of MX (0.5% and 0.25%), fosthiazate (standard and double concentrations) and culture dilution of Paenibacillus polymyxa GBR-1 ($10^7$colony-forming units/ml) reduced significantly the nematode populations in the cymbidium culture medium, compared to non-treatment control, with no significant difference among the treatments. No phytotoxicity occurred in all treatments. pH of the medium with the time after treatment and growths of 2-year-old cymbidium were not significantly different among treatments. Considering the safety and price of the organic acids, use of MX in the processes for culturing cymbidium may be a practically reliable and eco-friendly way in the control of the quarantine nematode in cymbidium.

• Korean Journal of Plant Resources
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• v.23 no.4
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• pp.379-385
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• 2010

This study was carried out to develop cultivation techniques of Climacium japonicum in transparent pot. We analyzed effect of different soil moisture content, air exposure degree, bed soil and ground cover moss on the growth of Climacium japonicum. The best humidity condition in transparent pot culture was 60~80% and a mixture of bed soil with peatmoss : perlite as 7:3 ratio was effective to growth. Two holes(each diameter is 4 mm) in the cover were also effective to the growth and control moisture in the transparent pot. The best mixture of bed soil was moss with peatmoss : pelite(7:3) in the pot culture but price of moss is expensive, the moss treatment was not practical. Total of 10 moss species were selected as ground cover plant; Hypnum erectiusculum Sull. et Lesq., Thuidium kanedae Sak., Hypnum plumaeforme Wils., Trachycystis microphylla Lindb., Bryum argenteum Hedw., Hypnum oldhamii Jaeg., Funaria hygrometrica Hedw., Leucobryum glaucum Aongstr., Polytrichum commune Hedw. and Weissia controversa Hedw. The plant height of selected moss was smaller than that of Climacium japonicum so these moss were very effective to cover the ground.

• Journal of Plant Biotechnology
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• v.34 no.3
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• pp.253-261
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• 2007

This study was conducted to develop an antibiotics marker-free potato (Solanum tuberosum L., cv. Taedong valley) plant having resistance against two herbicides. Agrobacterium tumefaciens strain EHA105, harboring a binary vector plasmid pCAMBIA3300 containing bar gene under the control of a promoter CaMV35S and linked CP4-EPSPS genes driven by CaMV35S promoter, was used in the current study. The leaf segments of newly bred potato variety (cv. Taedong Valley) was co-cultured with Agrobacterium. Then, the regenerated individual shoots were excised and transferred to potato multiplication medium supplemented with 0.5 mg/L phosphinothricin. The shoots were rooted in MS medium without hormone and obtained putative transgenic plant E3-6. Integration of target genes into the E3-6 plant and their expression was confirmed by PCR, Southern analysis, and ELISA test. The tissue necrosis test on young leaf blade and shikimic acid accumulation test using the tissue of E3-6 plant were conducted to investigate the resistance to glufosinate-ammonium and glyphosate, respectively. The transgenic plants (E3-6) simultaneously showed a high resistance to both herbicides. The same results were surely obtained also in the whole plants foliar-treated with alone or mixture of two herbicides, glufosinate-ammonium and glyphosate.

• Journal of Plant Biotechnology
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• v.42 no.2
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• pp.111-116
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• 2015

Interest and great demand for blueberry (Vaccinium corymbosum) have increased, as V. corymbosum is now one of the most economically important crops in Korea. It is expected that blueberry production and the area planted for cultivation will increase consistently in the years ahead because of high profitability and the consumer's demand for healthy ingredients. Effective mass production of blueberry is urgently needed for commercial cultivation establishment, but a main limitation is lack of a propagation system that produces a disease-free plant material for commercial plantation. A large amount of research has focused entirely on developing tissue culture techniques for blueberry propagation. However, controlling fungal and bacterial contamination of woody plant material is extremely difficult. Our study was conducted to investigate the effect of biocide addition during the in vitro culture of blueberry on plantlet growth and contamination occurrence. Four biocides, including Plant Preservative Mixture ($PPM^{TM}$), vancomycin, nystatin and penicillin G, were used in varying concentrations during the in vitro propagation of blueberry. When nystatin was added into the medium at low concentrations, the overall growth of blueberry plantlets was retarded. Addition of vancomycin and penicillin G in high concentrations decreased contamination but induced plantlet mortality. On the other hand, when 1ml/L $PPM^{TM}$ was added, the growth characteristics of blueberry plantlets did not significantly differ from non-treatment (control), and the contamination occurrence rate was very low. From these results, we found that the addition of the appropriate biocide could provide an effective method to reduce contamination in the culture process, thereby raising in vitro production efficiency.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.551-566
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• 1997

Phosphorus has been known as an essential component of animal body. However, the requirement has not been determined precisely because of the variable bioavailabilities of feedstuffs from plant origin. The bioavailability of P in various feedstuffs of plant origin varies from 10 to 60%. Digestibility and availability of the P differed considerably depending on the feed. The lowest values were found for maize (under 20%), the highest for wheat and triticale (over 50%). This is due to the proportion of phytate and the presence of intrinsic phytase. And the digestive tract of monogastric animals does not contain sufficient amounts of phytase, an enzyme that hydrolyses the unavailable phytate complexes to available, inorganic orthophosphates. Microbial phytase supplementation improves the P availability, and both intrinsic plant and microbial phytase improves the availability of P in feedstuffs of plant origin. In a mixture of feeds with low and high activity of intrinsic phytase and/or supplemented by commercial phytase, the P availability is additive. However, in the light of current results it seems that exceeding the P availability equal to 60-70% is unrealizable even at large microbial phytase doses.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.360-366
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• 2010

In the course of a searhing environmental friendly antifungal compounds, we found that mixture of methyl esters of fatty acids obtained from soybean oil had potent control efficacy against barley powdery mildew (Blumeria graminis f. sp. hordei). In this study, ten alkyl fatty acid esters (AFAEs) were tested for in vivo antifungal activity against five plant diseases such as rice blast, rice sheath blight, tomato gray mold, tomato late blight and barley powdery mildew. Some AFAEs showed the most control efficacy against barley powdery mildew among the tested plant diseases. By 5-hr protective and 1-day curative applications, six AFAEs ($3,000\;{\mu}g/ml$), including methyl and ethyl palmitates, methyl and ethyl oleates, methyl linoleate, and methyl linolenate demonstrated both curative and protective activities against barley powdery mildew. In contrary, methyl laurate strongly controlled the development of powdery mildew on barley plants by curative treatment at a concentration of $333\;{\mu}g/ml$, but did not show protective activity even at $3,000\;{\mu}g/ml$. Under greenhouse conditions, the seven AFAEs ($1,000\;{\mu}g/ml$) except for methyl and ethyl stearates, and methyl caprylate also effectively controlled cucumber powdery mildew caused by Podosphaera xanthii. Among them, methyl and ethyl palmitates ($333\;{\mu}g/ml$) represented the most control activity of more than 68% against the disease. The results are the first report on the antifungal activity of methyl and ethyl esters of fatty acids against plant pathogenic fungi.