• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.695-703
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• 2014

We experimented with the effect of oleic acid and its appropriate concentration to prevent powdery mildew eco-friendly in a cucumber greenhouse cultivation. 'Baekbongdadaki' (Nongwoo Bio. co. Korea) was treated in the plastic greenhouse at Sangmyung University. We treated four levels of concentration of oleic acid, which were 0, 2000, 4000, 6000, and 8000 ppm. There were investigated diseased severity, diseased leaf area, control value, and pesticide injury. The degree of control values by oleic acid treatments was investigated at 3 days after treatment. The recurrence of powdery mildew was checked for 55 days. The day and night temperature in the greenhouse were controlled to 23 and $15^{\circ}C$ respectively. The humidity inside the greenhouse was not controlled to prevent outbreak of the disease. From the experimental results, oleic acid was very efficient to control powdery mildew. 2000 ppm of oleic acid was shown to be the most control efficiency without any pesticide injury. The recommended method to treat it was to spray three times every 3 weeks.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.123-126
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• 2011

To investigate the forecasting of plant disease and insect for an agricultural complex and farm in environment-friendly cultivation of Rice, environment-friendly agricultural five complexs and five farms were selected in Youngam and Naju area, Jonnam, Korea. Preventation objects of plant disease and insect were leaf blast, neck blast, sheath blight, bacterial leaf blight, and hopper. Factors of sheath blight occurrence in environment-friendly agricultural complex were a fast transplanting time and a narrow planting density. Bacterial leaf blight in rice occurred severely in the area under water. Rice growth in environment-friendly agricultural complex was decreased heavy drying by hopper appearance.

• Korean Journal of Environmental Agriculture
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• v.8 no.1
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• pp.7-16
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• 1989

Application of steam distillation on the analysis of pesticide residue in soil, water and crops was studied using the nitrogen distillation apparatus. Most pesticides which were extracted by organic solvents could be analyzed by the steam distillation method. For instance, distillations of PCNB, ${\gamma}-BHC$, ${\alpha}-or$ ${\beta}-endosulfan$, IBP, diazinon, fenthion, fenitrothion, alachlor, butachlor, pretilachlor, metolachlor, pendimethalin, benthiocarb and molinate were possible, but not simazine, atrazine and nitrofen. The optimum volume of distillate for a sufficient extraction of pesticide varied according to kind of pesticide. In general, the volume needed was little for carbamate, but much more for organochlorine. When the definite amount of distillate was obtained and then the condenser was washed by acetone, the optimum volume of distillate was less. Using the steam distillation method, the amount of organic solvent needed for one extraction of pesticide from soil, water and vegetable was less than the conventional solvent extraction method, and the analytical procedure became simpler. The process of concentration and clean up was mostly unnecessary, although a ghost peak was apparent in the gas chromatogram according to the kind of materials distilled.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.257-263
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• 2012

Cosmetics using natural materials which was purchased in retail stores, distributed in Gyeonggi province(32 samples) and online through internet(24 samples) were analyzed by pesticide residues and target preservatives for assessing the safety of it. Natural or organic certifications was identified in 22 samples among 56 samples and most of them were Ecocert. Pesticide residues was detected in 3 samples among 56 samples and each compound and concentration was permethrin(0.6 mg/kg), tricyclazole(11.7 mg/kg) and malathion(0.05 mg/kg). All of it was purchased through internet. Target preservatives was detected in 13 samples among 56 samples and one of them was over the maximum allowed concentration and the rest of them were within the maximum allowed concentration of the respective preservatives. The compound which was over the maximum allowed concentration was benzoic acid and compounds which were within the maximum allowed concentration were sorbic acid, benzoic acid and methylparaben. They were all identified substances in products and the number of detected preservatives in retail stores were higher than online samples purchased through internet. As a result of this study, The method of analyzing pesticide residues and limit in cosmetics using natural materials should be set up as soon as possible and the monitoring about preservatives in cosmetics using natural materials should be conducted on continuously.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1071-1081
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• 2015

Environment-friendly agricultural products are consumed widely, but little is known about consumers' acceptability. The objectives of this study were to 1) determine consumers' acceptability of cucumber when consumed raw, 2) determine differences in appearance liking between environment-friendly and conventionally grown cucumber samples, and 3) analyze the physicochemical properties of cucumber. White dadagi, gasi, non-pesticide mini cucumber, organic gasi, and organic Joseon cucumber samples were evaluated for consumers' acceptability using a nine-point hedonic scale; White dadagi, organic Joseon, and organic gasi cucumber samples showed the highest acceptability scores. However, there were three consumer segmentations differing their degree of cucumber liking and preference. Consumers liked the appearance of organic gasi best. Consumers' preference of cucumbers did not change upon evaluation of the acceptability of the appearance of whole fruit with and without a label indicating an environment-friendly status. Additionally, the physicochemical properties of the cucumbers-including color (skin and flesh), length, circumference, weight, water activity, brix, and texture (hardness and fracturability)-were measured. All measurements showed significant differences among samples, with the exception of water activity and hardness. White dadagi was 3.8 brix, which was the highest among cucumbers, followed by non-pesticide mini cucumber and organic Joseon. White dadagi, organic Joseon, and organic gasi showed greater fracturability than the other cucumber samples.

• The Korean Journal of Pesticide Science
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• v.15 no.1
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• pp.55-60
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• 2011

To work out quality control methods of environmental-friendly organic materials (EFOMs), the reason and basis for EFOM-selection and farmer's favorite formulation type of EFOMs, etc were investigated on farmers who had been practicing environmental-friendly agriculture. EFOMs used were soil amendments, control agents of plant diseases and insect pests, plant growth promotion formulations, in turns. In EFOMs application time, 22.7% of farmers sprayed EFOMs without delay after they were bought, in other hand, 77.3% of farmers used EFOMs which had been bought and stored for some period. Microbial density on seventeen environmental-friendly microbial formulates (EFMFs) including microbial pesticides, a microbial fertilizer, and environmental-friendly organic materials was investigated at different storing temperature and shelf life. When the microbial density of EFMFs was investigated without delay after they were bought, all used microbial pesticides and a microbial fertilizer was confirmed to be optimal for the certified density but two of environmental-friendly organic materials was confirmed not to be optimal. When microbial density of 17 EFMFs were investigated after storing them for six months at $4^{\circ}C$, only one of 9 microbial pesticides was confirmed not to be optimal, the other hand four of seven environmental-friendly organic materials not to be optimal, which each of their microbial density was less than the certified density. Population dynamics of microbial agents was much more influenced in fluctuated temperature (room temperature) than in static temperature condition ($5^{\circ}C$ and $25^{\circ}C$). Shelf life of microbial agents according to microbial formulation type were high in granule type, liquid wettable type and liquid type in turns.

• Journal of Applied Biological Chemistry
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• v.58 no.4
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• pp.291-294
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• 2015

Persistent organic pollutants (POPs) including banned organochlorine pesticides, are found in Korean agricultural environments. Their translocation from agricultural environment to major crops has been reported. In this study, the POPs in 15 different agricultural waters of the Chungchung Province were monitored and all samples were prepared, followed by liquid-liquid fractionation and column chromatography prior to analysis using gas chromatography. Among pesticide-originated persistent organic pollutants, ${\alpha}$-endosulfan was determined in the range of 0.01 to 1.13 ng/mL. ${\beta}$-Endosulfan was determined in the range of 0.01 to 0.55 ng/mL, and endosulfan sulfate was ranged from 0.13 to 1.13 ng/mL. The total sum of endosulfans reached the range of 0.38 to 1.18 ng/mL. Three pesticides being used currently were also found in samples as 2.03-2.05 ng/mL for triadimefon, 0.26-0.33 ng/mL for tolyfluanid, and 1.34-3.85 ng/mL for chlorpyrifos. Taken together, endosulfans were introduced in the agricultural waters and their fates need continuous monitoring.

• 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.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.376-382
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• 2014

The soluble loess-sulfur mixture allowed standing to remove insoluble component materials for five weeks after manufacturing. We decreased the pH level of soluble loess-sulfur mixture at pH 1.0 modified with decreasing 25% sodium hydroxide than original content. The pH ranges of soluble loess-sulfur mixture solutions were adjusted to pH 5.0-pH 11.0 (pH 1 unit) with brown rice vinegar (pH 2.8). The pH of original loess-sulfur mixture was about pH 13 and damaged the foliar parts and young leaves of tomato after twice application. These stock solutions can be diluted 500:1 with tap water to make a 0.05% working solution and were sprayed two times with 7 days interval to the leaf and stem of tomato, which were spontaneously infected with E. cichoracearum. Control efficacy of powdery mildew ranged from 85% to 90% at 7 days after first application. After second application, each loess-sulfur mixture solutions adjusted pH level significantly suppressed the powdery mildew disease in tomato. Consequently, loess-sulfur complex adjusted pH level with brown rice vinegar was suggested to be low in acute toxicity at all different pH values and suggested to use an agent for control of tomato powdery mildew in organic farming.

• The Korean Journal of Pesticide Science
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• v.13 no.2
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• pp.117-125
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• 2009

Phenylformamidine derivatives are well known as insecticides for their specific activity against the insects. It has now been established that they show insecticidal activity as agonists on the octopamine receptor which is located in the synapse membrane. The reaction of triethylorthoformate and fluoroanilines gave formimidates (1) in good yields and N',N'-Disubstituted N-fluorophenylformamidine derivatives were synthesized more easily by using microwave. This microwave reaction condition gave products in high yields and faster reaction time than conventional methods. All the compounds were screened for their biological activity agaist harmful insects of plant hoppers, moths, aphids and mites. Synthetic compounds of 2-I-a, 2-I-c, 2-I-d, 2-II-d showed good activity against mites and plant hoppers.