• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.507-512
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• 2011

This study was carried out to investigate the chemical characteristics of different organic liquid fertilizer during fermentation at plastic house in Chungbuk Agricultural Research and Extension Service. Chicken dung, soybean meal, and rice bran were used for nutrient sources. The obtained results from this study were summarized as follows; Total nitrogen contained the highest in soybean meal as 55 mg·kg^-1, and phosphate and potassium contained high in chicken dung and rice bran in organic liquid fertilizer materials. The pH of chicken dung was near 7.0, that of soybean meal and rice bran indicated acidity(pH 3.8~4.4). The electrical conductivity of chicken dung consistently increased during fermentation, and that of soybean meal and rice bran increased and decreased early season and increased at late incubation period. Hydrogen sulfide gas occurrence of chicken dung was 3,200 mg·L^-1 at early season and 1,600 mg·L^-1 at late incubation period, and that of soybean meal and rice bran treatments were not or very low concentration of hydrogen sulfide gas during manufacturing period. The nitrogen and calcium content of organic liquid fertilizer were the higher in chicken dung and soybean meal than rice bran. The phosphate and magnesium content of rice bran was the high as 5.6 g·kg^-1 and 1.5 g·kg^-1, respectively. There was no difference in potassium content among the different liquid fertilizers during fermentation.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.272-281
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• 2010

The objective of this research was to find out the weed management techniques in environment-friendly rice paddy fields through the study on herbicidal effects and problems of various organic materials. This experiment was conducted under different conditions of weed species and weed densities in environment-friendly rice paddy fields. There was no difference in weedy efficacy on golden apple snail (GAS), paper mulching (PM), and machine weeding (MW) between low and high weed densities. However, the effect of weed control in rice bran (RB) and effective microorganism (EM) + molasses was higher in high weed density than in low weed density. In general, the effect of weed control as affected by various organic materials was in the order of GAS (97-100%) > PM (93-98%) > RB (15-80%) > EM (7-31%). GAS provided excellent control of all weed species tested except for Persicaria hydropiper. PM gave acceptable control of the weed species except for Echinochloa crus-galli, Ludwigia prostrata, and Eleocharis kuroguwai. However, MW gave fair control (70% biomass reduction) of all weed species tested. BR followed by MW or EM followed by MW treatments had similar effect on weed control compared to each treatment alone. However, BR followed by GAS or EM followed by GAS provided 100% control of weed species tested. The level of rice foliar injury caused by various organic materials was in the order of GAS and MW (10-20%) > RB (10-15%) > PM and EM (5-7%). Typical symptoms of organic materials are wilting, inhibition of growth, missing hill, and reduction of tiller. Cost for weed control of GAS, RB, EM, and PM were 2.1, 3.1, 2.3, and 13.2 times higher than that of the herbicide. These data indicate that GAS was the best method for weed management in environmentfriendly rice paddy fields. Further study is required to elucidate the mechanisms underlying the rice injury as affected by GAS.

• The Korean Journal of Community Living Science
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• v.21 no.4
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• pp.481-488
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• 2010

The objective of this study was the development of the preparation method of fermented turnip juice. The yields and soluble solids of fermented turnip juice were 41.2, 52.8, 56.4 and 57.4%, and 34.3, 42.4, 48.6 and 54.7 $^{\circ}Brix$ with 40, 60, 80 and 100% addition rate of turnip quantity, respectively. The major organic acids in turnip juice were succinic acid, isobutyric acid and fumaric acid, and these organic acids were decreased after fermentation. On the other hand, lactic acid, formic acid, acetic acid, propionic acid and butyric acid were produced during the fermentation. Soluble solid and pH value in fermented turnip decreased by time-dependently. Free radical scavenging activity was increased by fermentation of turnips and nitrate scavenging effects were the highest in pH 3 and increased with adding Omija or Japanese apricot. The best preparation method of fermented turnip juice was fermentation at $24^{\circ}C$ 12-15 days after adding 40% of sucrose to total quantity. As adding Omija, organic acid contents were increased and sensory evaluation was improved in fermented turnip juice.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.286-286
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• 2009

벼 유기재배시 토양양분공급용으로 이용되고 있는 유기자재(금수강산골드)를 대조로 하고 식물성유기 자재(쌀겨팰렛), 동물성유기자재, 식물성과 동물성이 혼합된 유기자재를 질소 성분량(7kg/10a)을 기준으로 하여 이앙 20일전에 전량 기비로 시비하고 경운한 다음 동진1호를 시험품종으로 하여 2년연속 유기 자재와 벼를 재배하면서 일어나는 토양의 이화학적 특성과 벼 생육 및 특성의 변화를 시기별로 조사하였다. 시험 전 토양의 화학성은 전반적으로 유기물은 높고 인산함량은 매우 낮은 조건의 토양이었다. 관행유기자재(금수강산골드)는 20일경에 50% 무기화율을 보였으나, 식물성자재 40~60일경, 동물성자재와 혼합자재(식물성+동물성)는 60~80일경에 47~52% 무기화 정도를 나타내 식물성 자재의 무기화 속도가약 20일정도 빨랐다. 토양 중의 유기물 잔존함량은 식물성자재 > 혼합자재 > 동물성자재 > 관행 순이었으며, 토양 중의 전 질소 잔존함량의 경우 관행유기자재는 처리초기부터 빠르게 감소하는 특성을 보이나, 식물성자재와 혼합 자재는 시비초기와 거의 비슷한 수준을 유지하였고, 동물성 자재는 서서히 감소되는 경향이었다. 토양 물리성은 액상과 공극율 다소 증가되는 경향이었으며 식물성과 혼합유기자재처리구가 컸으며, 토양 유효 입단 형성력에 있어서도 유사한 경향이었다. 벼 수량 특성은 관행유기자재보다 1년차에는 3~9%의 낮았으나, 2년 연속처리를 할 경우 관행유기자재를 처리할 때와 동일한 생산성을 기대할 수 있었다. PME와 $\beta$-Glucosidase의 효소활성은 관행유기자재 < 식물성자재 < 동물성자재 < 혼합유기자재의 순으로 높은 경향을 볼 수 있었다.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.285-285
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• 2009

벼 유기재배에 있어서 녹비작물을 이용하여 화학비료를 대신하고 있으나 녹비를 이용하기 위해서는 월동 전에 파종하고 이듬해 벼 이앙 전에 토양에 환원을 해야 하는 번거로움이 있다. 따라서 벼 재배 직전에 유기자재를 이용하여 화학비료를 대신하고자 했을 경우 유기자재를 전층시비와 표층시비의 차이에 따른 토양중의 이화학적 특성과 벼의 수량특성의 변화를 구명하였다. 벼 유기재배시 토양양분공급용으로 이용되고 있는 유기자재 4종을 공시하여 유기자재의 질소 성분량(7kg/10a)을 기준으로 하여 이앙 20일전에 시비방법별로 전층시비와 표층시비 2처리로 구분하여 전량 기비시비하고 경운한 다음 동진1호를 시험품종으로 하여 2년 연속 시비처리와 벼를 재배하면서 일어나는 토양의 이화학적 특성과 벼 생육 및 특성의 변화를 시기별로 조사하였다. 시험 전 토양의 화학성은 표층시비구의 염류농도, 가리와 석회의 함량이 다소 높아서 염류농도가 전층 시비구 보다 높은 조건의 토양이었다. 유기자재별 무기화 정도는 전층시비보다 표층시비를 할 때 약 20~30일 정도 빨랐다. 토양 중의유기물 잔존함량은 시비방법간의 큰 차이는 없었으나 표층시비를 할 경우 후기로 갈수록 다소 증가되는 경향이었으나, 전질소 잔존함량은 감소되었다. 토양 액상과 공극율은 전층시비>표층시비였으며, 입단 형성력도 같은 경향이었다. 토양 효소활성은 PME의 활성은 유기자재를 전층처리하였을 때 촉진되었으며, $\beta$-Glucosidase의 활성은 전층보다 표층처리시 활성이 높았다. 시비방법에 따른 벼의 수량 특성은 시비방법별로는 표층시비를 할 경우 전층시비보다 4~7%의 높은 특성을 보였으며, 관행대비 1년차에는 3~9%의 낮았으나, 2년 연속처리를 할 경우 대조구와 비슷해 지는 경향이었다.

• The Plant Pathology Journal
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• v.37 no.6
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• pp.580-595
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• 2021

Although late blight is an important disease in ecofriendly potato cultivation in Korea, it is highly dependent on the use of eco-friendly agricultural materials and the development of biological control technology is low. It is a necessary to develop an effective biocontrol agent to inactivate late blight in the field. AFB2-2 strain is a gram-positive with peritrichous flagella. It can utilize 20 types of carbon sources, like L-arabinose, and D-trehalose at 35℃. The optimal growth temperature of the strain is 37℃. It can survive at 20-50℃ in tryptic soy broth. The maximum salt concentration tolerated by AFB2-2 strain is 7.5% NaCl. AFB2-2 strain inhibited the mycelial growth of seven plant pathogens by an average inhibitory zone of 10.2 mm or more. Among the concentrations of AFB2-2, 10⁷ cfu/ml showed the highest control value of 85.7% in the greenhouse. Among the three concentrations of AFB2-2, the disease incidence and severity of potato late blight at 10⁷ cfu/ml was lowest at 0.07 and 6.7, respectively. The nucleotide sequences of AFB2-2 strain were searched in the NCBI GenBank; Bacillus siamensis strain KCTC 13613, Bacillus velezensis strain CR-502, and Bacillus amyloliquefaciens strain DSM7 were found to have a genetic similarity of 99.7%, 99.7%, and 99.5%, respectively. The AFB2-2 strain was found to harbor the biosynthetic genes for bacillomycin D, iturin, and surfactin. Obtained data recommended that the B. velezensis AFB2-2 strain could be considered as a promising biocontrol agent for P. infestans in the field.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.275-276
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• 2009

민간단체들에 의하여 자율적으로 시작된 국내 유기농업은 친환경농업육성법(1997. 12.13)이 제정되면서 국가기관의 친환경농업 활성화 노력과 더불어 2008년 유기농재배 농가(8,460호)와 면적(12,033호)이 급격히 증가되었다. 또한 유기농업의 확산과 더불어 화학비료 및 유기합성 농약대체 친환경농자재들의 유통이 증가되고 있으나 관리규정이 없어 검증되지 않은 다양한 농자재들이 유통되어 친환경실천 농가들의 혼란이 초래되어 국정감사 시 문제점으로 지적과 함께 각계에서 관리제도의 필요성이 대두되었다. 친환경농업육성법 시행령 개정(대통령령 제19964호, 2007.3.27.공포, 2007.3.28.시행)으로 농촌진흥청에 친환경농자재심의회가 설치되어 효과와 효능을 검증하지 아니하고 친환경농산물 중 유기농산물 생을 해 사용가능한 자재인지 여부를 검토하여 그 결과를 공개하는 목록공시제가 마련되었다. 친환경유기농자재 목록공시는 1년에 4회 매분기말에 농촌진흥청 농자재관리과에서 접수를 받아 친환경농자재 분야별 전문위원회 검토 후 심의위원회 심의를 거쳐 접수일로부터 90일 이내에 농촌진흥청장이 공시(농진청 홈페이지, 관보게재)하고 친환경농업 관련기관 및 검토 신청자에게 통보함으로서 마무리된다. 목록 공시된 친환경유기농자재의 유효기간은 2년이다. 친환경농자재심의위원회는 토양개량 및 작물생육분야 전문위원회 위원 11명, 병 해충 관리분야 전문위원회 위원 11명 및 심의위원회 의원 20명으로 구성되어 있다. 2007년 3월부터 2009년 11월 30일 현재 목록 공시된 친환경유기농자재 제품은 (1) 양개량용 자재 25 개, (2) 작물생육용 자재 282개, (3) 토양개량 및 작물생육용 자재 308개, (4) 작물병해 관리용 자재 110개, (5) 작물충해 관리용 자재 : 224개, (6) 작물병해충 관리용 자재 5개 및 (7) 기타 자재 1개 제품으로 총 955개 제품에 이르고 있다. 한편, 공시연장 미신청, 현재 검토기준안에 필요로 하는 추가요청 자료 미제출 및 공시이외의 물질 사용으로 국내유통 중 단속되어 부적합한 판정을 받아 20여 제품이 목록공시가 취소되었다. 앞으로 목록 공시되는 친환경유기농자재는 제품의 주성분 함량 표기, 시용효과 검정방법 선, 제조방법 현장점검, 안전성 검정 등 여러가지 제도보완 및 사후관리 방안이 시급히 마련되어야 할 것으로 사려된다.

• Current Research on Agriculture and Life Sciences
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• v.33 no.1
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• pp.15-18
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• 2015

Zein/Poria cocos extract nanofibers were prepared based on the electrospinning of aqueous solutions with different Poria cocos extract concentrations (0, 5, 10, and 15 wt.%). The electrospinning parameters, including the polymer contents, voltage, and tip-to-collector distance (TCD), were optimized for the fabrication process. The resulting electrospun materials were all characterized using field-emission scanningelectron microscopy (FE-SEM). The diameters of the electrospun zein nanofibers were found to increase when increasing the zein concentration.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.138-143
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• 2011

BACKGROUND: This study was conducted to investigate growth and yield of organically grown rice under a typhoon during a fall. The treatments included NPK chemical fertilizer, compost, oilcake, oilcake 2X, hairyvetch, and vetch+rye. METHODS AND RESULTS: Nutrient applications were made at rates equivalent to approximately 0.9 kg of actual N per acre. Oilcake and hairyvetch treatments had the lowest C:N ratio, but compost had the highest C:N ratio of 34:1. Rice treated by organic nutrient sources had great growth and development at the beginning of the growing season but had depressed growth and yield at the harvest. Oilcake 2X-treated rice in early growing season, especially, showed better growth and development than rice treated by other nutrient sources but was severely lodged at the harvest season due to the typhoon. Compost treatment with high C:N ratio slowly released inorganic N and produced poor rice growth and yield; however, it recued rice lodging. N uptake was the greatest for the oilcake 2X and vetch+rye treatments but the lowest for the compost, which was the similar pattern to the N use efficiency; the greatest and lowest N use efficiency was observed for the oilcake 2X (55%) and compost (5%), respectively. CONCLUSION(s): Rice lodging should be prevented by reducing the excessive nitrogen supplement, resulting from the lower C:N ratio of the organic materials as well as prevented by the radical midsummer drainage. Vetch+rye treatment with 25:1 of C:N had optimum vegetative growth and reduced rice lodging, which increased N use efficiency and yield.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.739-746
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• 1999

Discharge characteristics of organic materials and nutrients were estimated in the catchment area of relaimed area-Saemankeum-. Discharge load of BOD5 was high in the domestic system, while nitrogen and phosphorous were discharged mainly from the livestock system and the land . Load was so dependent on the precipitation that it increased in the rainy season, particulary in nitrogen and phosphorus. Loads from nonpoint sources in this area were higher compared with others.