• Korean Journal of Soil Science and Fertilizer
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• v.49 no.3
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• pp.251-258
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• 2016

A rhizobacterium LPN-2, which showed strong antifungal activity and auxin producing ability, was isolated from a farmland in North Gyeongsang Province, South Korea. Based on analysis of the 16S rDNA sequence, strain LPN-2 was identified as a novel strain of Burkholderia and was designated as Burkholderia sp. LPN-2. In vitro experiments showed that the isolated stain LPN-2 significantly produced auxin within 48 hr incubation. In order to check for PGPR function we performed in vivo growth promoting test in different crops, including mung bean, pea and cabbage. Application of Burkholderia sp. LPN-2 showed dramatic growth promoting effect on all the tested plants. We also confirmed siderophore and cellulase productions by Burkholderia sp. LPN-2 using CAS blue agar and CMC plate test. Further treatment with LPN-2 and the crude culture broth was effective in suppressing anthracnose in vitro test and also reduced incidence and severity of anthracnose in apple and pepper. Taken together, we conclude that Burkholderia sp. LPN-2 might be used as organic fertilizer for effective crop production in organic farming.

• Korean Journal of Organic Agriculture
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• v.10 no.3
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• pp.87-99
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• 2002

The development of insecticidal soaps made by various fatty acids and organic control for insect by using of insecticidal soap(fatty acid salts) were employed. And the results were as follows: 1. To determine the input volume of potassium hydroxide for saponification of fatty acids, there were compared to individual acid value of fatty acids. in case of coconut fatty acids for saponification was 266.3 mg of potassium hydroxide(266 g/1kg of fatty acid) was calculated. 2. To make the 25% soap content by coconut fatty acids, there was required for the 266g of potassium hydroxide and 3,459 liter of soft water. Then the liquor of soap was 4,644 liter. 3. The progress of insecticidal soap made by fatty acids was accomplished indirect heating and stirring reactor (1)to make the volume of potassium hydroxide solution and warming up(90$^{\circ}$) (2)input volume of individual fatty acid (3)more than 30 min stirring reaction (4)cooling progress. 4. Insecticidal value of insecticidal soap was observed more than 92% the dilution of 50 dilution solution in consecutive 5 days of 2 treatments of the 25% soap made by coconut fatty acids on the red pepper. And insecticidal value of insecticidal soap was observed more than 94% the 100 dilution solution in consecutive 5 days of 3 treatments of the 25% soap made by coconut fatty acids on red pepper and cabbage. 5. The treatment of two times of 25% soap made by coconut fatty acids at the 50 dilution solution and 100 dilution solution in spider mite on red bean has 100% insecticidal value. 6. There was no observation phytotoxic sypmtons on red pepper in field, except for 25% soap made by carprylic acid. 7. Over the two times over 0.1% in addition of isopropyl alcohol was to improvement the insecticidal effect, but there was no effect in addition of diatomaceous earth.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.4
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• pp.266-273
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• 2009

Use of plant growth promoting symbiotic and non-symbiotic free-living beneficial bacteria as external source of nitrogen is a major research concern for sustainable crop production in the $21^{st}$ century. In view of this, an experiment was conducted under controlled conditions to determine the effects of inoculation with Methylobacterium suomiense CBMB120, a plant growth promoting (PGP) root and shoot colonizer on red pepper, for the purpose of reducing external chemical nitrogen fertilization. Amendments with organic fertilizer and chemical fertilizer in the form of NPK were made at dosages of 50%, 75% and 100%, at 425 and $115kg/ha^{-1}$ measurements. The soil type used was loam, with a pH of 5.13. The growth responses were measured as plant height at 19, 36 and 166 days after transplantation and final biomass production after 166 days. It was found that inoculation with M. suomiense CBMB120 promotes plant height increase during the active growth phase at 19 and 36 days by 14.17% and 10.03%, respectively. Thereafter, the bacteria inoculated plantlets showed canopy size increment. A highly significant inoculation effect on plant height at p<0.01 level was found for 100% level of organic matter and chemical amendment in red pepper plantlets after 36 days and 19 days from transplantation. Furthermore, there was a significantly higher (10.30% and 6.84%) dry biomass accumulation in M. suomiense CBMB120 inoculated plants compared to un-inoculated ones. A 25% reduction in the application of chemical nitrogen can be inferred with inoculation of M. suomiense CBMB120 at with comparable results to that of 100% chemical fertilization alone. Enumeration of total bacteria in rhizosphere soil confirms that the introduced bacteria can multiply along ther hizosphere soil. Large scale field study may lead to the development of M. suomiense CBMB120 as an efficient biofertilizer.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.343-349
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• 2013

Environment-friendly agro-materials tend to be preferred to chemical insecticides recently. For this reason, many studies are conducted to develop environment-friendly insecticides containing natural materials. The purpose of this study was to assess ecotoxicity for pepper extract and cassia oil (11.5+46%, A), pepper extract and cassia oil (23+34%, B), and pepper extract and lavender oil (40+10%, C). They are expected to prevent from pests especially diamondback moth, and can be used for agro-materials. Their formulation was emusifiable concentration (EC). Target species used to assess acute toxicity were aquatic invertebrate (Daphina magna), fish (Cyprinus carpio), honeybee (Apis mellifera L.) and earthworm (Eisenia fetida). The $EC_{50}$ value of A, B, and C to aquatic invertebrate were 0.46, 1.9, 0.25 mg $L^{-1}$ respectively and these values were moderately toxic according to standard of USEPA. In case of acute toxicity test to fish, the $LC_{50}$ of A, B, and C were 1.9, 2.9, 3.8 mg $L^{-1}$ respectively. A was category II in acute toxicity of fish and not acceptable to evaluation criteria of environment-friendly agro-materials. B and C were category III and acceptable. Acute contact and oral toxicity test to honeybee were conducted and the $LD_{50}$ of A, B, and C were > 100 ${\mu}g$ a.i. $bee^{-1}$ in both of tests. It indicated they were low toxic to honeybee. In case of acute toxicity test to earthworm, $LC_{50}$ of A, B, and C were 695, 988, and 564 mg $kg^{-1}$. In conclusion, pepper extract+cassia oil 57% EC and pepper extract+lavender oil 50% EC were expected to be used for environment-friendly insecticide materials with low risk against ecosystem and contribute to developing environment-friendly agro-materials.

• Journal of Environmental Science International
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• v.23 no.11
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• pp.1827-1833
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• 2014

This study has been carried out to present the valuation system of soil carbon sequestration potentials of soil in accordance with the new climate change scenarios(RCP). For that, by analyzing variation of soil carbon of the each type of agricultural land use, it aims to develop technology to increase the amount of carbon emissions and sequestration. Among the factors which affects the estimation of determining the soil carbon model and influence power after the measurement on soil organic carbon, under the center of a causal relationship between the explanatory variables this study were investigated. Chemical fertilizers (NPK) decreased with increasing the amount of soil organic carbon and as with the first experimental results, when cultivating rice than pepper, the fact that soil organic carbon content increased has been found out. The higher the carbon dioxide concentration, the higher the amount of organic carbon in the soil and this result is reliable under a 10% significance level. On the other hand, soil organic carbon, humus carbon and hot water extractable carbon has been found out that was not affected the soils depth, sames as the result of the first year. The higher concentration of carbon dioxide, the higher carbon content of humus and hot water extractable carbon content. According to IPCC 2006 Guidelines and the new climate change scenario RCP 4.5 and the measurement results of the total amount of soil organic carbon to the crops due to abnormal climate weather, 1% increase in atmospheric carbon dioxide concentration was found to be small when compared to the growing rate of increasing 0.01058% of organic carbon in the soil.

• The Korean Journal of Pesticide Science
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• v.19 no.4
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• pp.402-410
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• 2015

The purpose of this study was to estimate the chitinolytic and antifungal activity of Actinomycetes sp.isolated from waste mushroom media. In five kinds of waste mushroom media, Sinyeong mushroom and Yangsongi were the order of the population density of actinomycetes. Totally 91 chitinolytic isolates of Actinomycetes sp. were obtained from waste mushroom media. The isolates were categorized into 3 groups based on chitinolytic activity and antagonisms against Phytophthora capsici, Rhizoctonia solani, Sclerotinia sclerotiorum, Collectotrichum gloeosporioides, and Cladosporium cucumerinum in vitro. CA-23 was selected as a representative isolate of a group showing strong chitinolytic and antagonistic activities to all of the plant pathogens, while AA-65 was selected as a representative isolate showing no chitinolytic activities but strong antagonistic activities to the pathogens. CA-23 and AA-65 were highly effective on control of Phytophthora blight of hot-pepper, powdery mildew and scab of cucumber in a greenhouse tests. Among the isolates tested, CA-23 showed highest control efficacy, while AA-65 not only effectively controlled the diseases but also consistently increased plant growth and yield. Although the isolates are similarly affected on suppression of plant pathogens, the isolates could be differ from each other in modes of action. Further studies on mechanisms and practical applications are being progressed.

• Weed & Turfgrass Science
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• v.3 no.3
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• pp.215-220
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• 2014

This study was conducted to evaluate potential weed control in organic farming field using false seedbed and stale seedbed techniques. The experiment was conducted in open upland fields during spring and fall crop seasons. The false seedbed was prepared before 2-4 weeks of crop culture and was treated with shallow tillage or flame weeding before transplanting. The weed suppression rates of false seedbed treatment in the spring crop experiments for Chinese cabbage, soybean, hot pepper and corn were 65-73%, 50-55%, 9-55% and 8-33%, respectively. According to crop growth and yield in this experiment, the false seedbed technique has some potential weed control for Chinese cabbage, soybean and corn. The weed suppression rates of stale seedbed treatments in the fall crop experiments for Chinese cabbage, spinach and carrot were 18-39%, 40-77% and 37-38%, respectively. Weed control efficacy of the stale seedbed in this study was lower, when compared with false seedbed.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.4
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• pp.303-308
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• 1994

We have obtained following results by executing this experiment to define effects of organic substances applied and temperature on fungistatic effect which is regarded as basic factor of inhibition against hot-pepper blight affection : 1. Fungistatic effect of soil on Phytophthora capsici is enlarged by application of organic material such as rice straw rather than matured composts. Morever, it is confirmed that fungistatic efect is more eminent at the temperature of $15^{\circ}C$ and $5^{\circ}C$ than at $30^{\circ}C$, Degree of fungistatic effect of soil tends to decrease as the goe on from the moment of using organic substance generally, in soil applied as the goes on from the moment of using organic substance generally, in soil applied rice straw it is prove that fungistatic effect is maintained stably in a long term. 2. Effect of applicating organic substances and treating by temperature on production of zoosporangium of Phytophthra capsici is reviewed. In case that sterilized soil solution is added on cultured hypae of Phytophthra capsici, increase in the production of zoosporangium is found which is statistically significant(at degree of 1%), while decrease effect statistically significant is found in case of adding soil solution used for applying bark compost. However, defferences between treatments of temperature is not found. On the other hand, when nonsterilized soil solution is added, significant defference between types of organic substance is not found, while significant difference is found between treatments of temperature, therefore formation of zoosporangium is increased at the condition of $5^{\circ}C$ comparing to that of $30^{\circ}C$. 3. Putting above result of examination concerning to composition of soil microrganisms in each treated soil and to fungistatic effect of them, it seems that fungi and bacteria in soil is mostly related to fungistatic activity of soil.

• Mycobiology
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• v.45 no.1
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• pp.20-24
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• 2017

We investigated the effects on various crops of inoculation with species of arbuscular mycorrhizal fungi (AMF) in soils from different sources and selected AMF species suitable for domestic environment-friendly farming. Effects on plants varied with the AMF species used. In carrot, Scutellospora heterogama, Acaulospora longula, and Funneliformis mosseae had a positive effect on growth of the host, whereas AMF had only weak effects on the growth of red pepper and leek. AMF inoculation had positive effects on the growth of carrot and sorghum. The results of this study indicate the nature of the relationship between soil, plants, and AMF; this study therefore has important implications for the future use of AMF in environment-friendly agriculture.

• Journal of Life Science
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• v.9 no.6
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• pp.743-752
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• 1999

The purpose of the paper is to explore the current knowledge on the nutritional evaluation, cholesterol-lowering effect and antitumor activity of kimchi and its ingredients(Korean cabbage, garlic, red pepper powder, ginger and onion). Kimchi contains high contents of nutrients such as vitamins(ascorbic acid, $\beta$-carotene and vitamin B complex), minerals(calcium, potassium, iron and phosphorous), essential amino acids and dietary fiber. Kimch also contains high levels of lactic acid bacteria, allicin, capsaicin, organic acid, phenol compounds, flavonoid and sulfur compounds. The dietary fiber and lactic acid bacteria isolated from kimchi are effective in improving intestinal microflora of human. Isoluble dietary fiber shows anticancer activity, but soluble dietary fiber shows hypocholesterolemic effect. Lactic acid bacteria isolated from kimchi acts as a hypocholesterolemic or anticancer agent. A major ingredient of kimchi is mainly cruciferous and allium family vegetables, which were also reported to prevent cancer and atherosclerosis. It is suggested that kimchi is important not only as one of the traditional fermented Korean food but also as therapeutic agent for carcinogenesis and hypercholesterolemic state.