• Korean Journal of Weed Science
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• v.30 no.3
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• pp.243-251
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• 2010

The study was conducted to evaluate the weed suppressing effects of two winter cover crops, Chinese milk vetch (CMV) and rye, in minor cereal fields in 2009. The suppressing activities of cover crops were due to the allelopathy of cover crops during weed emerging periods and competitive activity during vegetative growth of weeds. Weed suppression by cover crops were changed from 26.5 g $m^{-2}$, 0.1 g $m^{-2}$ and 0.2 g $m^{-2}$ in control, rye field and CMV field, respectively, on June 22 to 428.6 g $m^{-2}$, 1 g $m^{-2}$ and 403.9 g $m^{-2}$ in control, rye field and CMV field, respectively, on July 22. The weed dry weights were further changed to 656.3 g $m^{-2}$, 607.8 g $m^{-2}$ and 511.8 g $m^{-2}$ in control, rye field and CMV field, respectively, on August 22. The suppressing effect of cover crops also observed in minor cereals. Plant height and dry weight of sorghum was reduced to 68.7% and 33.6% of handweeding, respectively, on August 5. The reduction was recovered to 82.7% and 55.6% of control, respectively, on August 26. In addition, heading date of minor cereals was delayed by 7 days with rye.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.271-276
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• 2012

A mycoparasite, Paraconiothyrium minitans CM2 was selected for biological control of sclerotinia rot of lettuce caused by Sclerotinia sclerotiorum. The experiment was carried out in a lettuce greenhouse in Yangpyeong from March to April.. When lettuce sclerotinia rot showed in the early stage of occurrence, Conidial suspension of the mycoparasite was weekly treated once to three times onto soil surface around lettuce plants. Incidence of sclerotinia rot in the once-application plot of the mycoparasite ($1{\times}10^7$ spores/$m{\ell}$) and in the benomyl(WP)-treated plot was 11.0% and 2.7%, respectively, whereas that of control was 31.0%. Incidence of twice- and three-application plots of the isolate was 7.9% and 12.8%, respectively. For increasing the effect of the mycoparasite, the experiment for the timing of application of P. minitans CM2 was carried out in a lettuce greenhouse in Yangpyeong and Suwon. Control efficacy against lettuce sclerotinia rot in the soil-drenching plots of P. minitans CM2 ($5{\times}10^6$ spores/$m{\ell}$) in the planting was 75.3~84.7%, and control effect by treatment of the isolate at the pot drenching+the soil-drenching plots in the early stage of disease occurrence was 63.8~58.0%. As the results, P. minitans CM2 could be a prospective biofungicide for biological control of sclerotinia rot of lettuce.

• Korean journal of applied entomology
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• v.41 no.4
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• pp.293-298
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• 2002

Cadusafos and fosthiazate were applied at the rate of 1.8 g a.i./6$\m^2$ as pre-plant or pre-plant＋post-plant treatments on winter-grown oriental melon in a greenhouse soil infested with Meloidogyne arenaria. Nematicides reduced root-knot nematode population from 35 to 90% compared with control； fosthiazate was better than cadusafos (P ＝ 0.003) and fosthiazate pre-plant＋post-plant application reduced nematode population densities as much as 90%. Nematicides increased yield in an average of 23% (11-38%) in May, 39% (2-65%) in June, and 31% (12-46%) for the total (P ＝ 0.085). The residue in the fruit of oriental melon by post-plant treatment of fosthiazate exceeded maximum residue limit of 0.2ppm, while the Cadusafos residue was below the limit. It is concluded that fosthiazate cannot be used as a post-plant treatment in winer-grown oriental melon with overall consideration, i. e., danger of residue, value of melon, costs of nematicide, consumer demand on safer agricultural products, and effects of fallow.

• Journal of agricultural medicine and community health
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• v.29 no.2
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• pp.249-263
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• 2004

Objectives: The objectives of the present study were to establish the exposure monitoring method of chlorpyrifos and chlorothalonil application to pear and field red pepper by vehicle-mounted sprayer, hand-held sprayer and to assess the risk. Methods and Results: Chlorpyrifos met all of requirements of sampling and analysis method(U.S. EPA), but chlorothalonil met only dermal patch method. Potential dermal and inhalation exposure was evaluated in 42 farmers. Compared with the hand-held sprayer application, vehicle mounted sprayer demonstrated producing relatively lower dermal exposure levels with statistical significance. In dermal exposure during hand-held application, there is no significant difference between pear and red pepper. Conclusions: This results show that application method is the main factor of dermal exposure. There was no statistically significant difference between each group of respiratory exposure level. The margin of safety (MOS) was calculated to assess the risk of pesticide exposure. All Chlorpyrifos MOS values are lower than 0.2, which mean working conditions are unsafe. In order to protect farmers, big efforts to control exposure are needed.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.351-358
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• 2006

This study was conducted to evaluate herbicidal properties of picolinafen in terms of crop safety, weed control spectrum, application window, residual efficacy and resistant weed control. Herbicidal phytotoxicity of picolinafen to wheat and barley was greatest when applied at 0 days after sowing (DAS), but decreased significantly as plant growth advanced. Picolinafen showed greater activity against broadleaved weeds than grass weeds. Picolinafen showed highest activity when it was applied at early post emergence timing (5 to 15 DAS), and showed significantly decreased activity at 20 DAS application. The $LT_{50}$ values (the period from application required for residual control by 50%) was 9.3 and 6.5 days against Digitaria ciliaris and Brasica naus at 60 g ai $ha^{-1}$, respectively. Picolinafen showed similar activities against both triazine resistant and sensitive Amaranthus retroflexus. Collectively, picolinafen appeared to have a good fitness to control resistant broad leaved weeds control by early post emergence application.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.23-28
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• 2007

Auxin-producing antagonistic bacterium K11, which can inhibit Phytophtora capsici, was isolated from a local red-pepper field soil in Gyeong-buk. In order to check for additional PGPR(plant growth promoting rhizobacterium) functions of the strain K11, we confirmed siderophore and cellulase productions by CAS (chrome azurol S) blue agar and CMC plate with congo red, respectively. The strain K11 was identified as Bacillus licheniformis with 98% similarity on 16s rDNA comparison and Biolog analyses. B. licheniformis K11 promoted mung bean adventitious root induction and enhanced root growth of mung bean (160%), pea (150%), and Chinese cabbage (130%), Also, B. licheniformis K11 was able to effectively suppress (63%) P. capsici causing red-pepper blight in the pot in vivo test. Therefore, we could select a triple-functional PGPR which has auxin, siderophore, and cellulase producing ability for effective crops production in organic farming.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.209-218
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• 2019

This study was conducted to develop a technology for environmentally friendly control of sweet-potato whitefly, Bemisia tabaci, by controlling their behavior using a push-pull strategy in a tomato greenhouse. B. tabaci was attracted the most by yellow color, light source of 520 nm, whereas it avoided the complex light treatment of 450 + 660 nm. The two natural enemies of B. tabaci, Cyrtopeltis tenuis and Orius laevigatus, were attracted the most by 520 nm light source. B. tabaci was repelled by the volatile organic compounds ocimene and carvacrol and was the most attracted by methyl isonicotinate. When buckwheat was added into the tomato greenhouse, the density of C. tenuis was maintained at about 16 times higher than when untreated for 15 days. As a result of the combined treatment of push-pull strategy, the density per trap of B. tabaci was three times lower than when no treatment was applied, and the control of this pest increased with time and reached up to 68.7%.

• 농업기술회보
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• v.46 no.1
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• pp.36-37
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• 2009

크리스마스를 상징하는 화려한 포인세티아는 겨울철의 대표적인 분화이다. 포인세티아 수요는 매년 괄목할 만한 성장을 하여 겨울 꽃시장의 주요 상품으로서 자리 매김을 하고 있지만 그동안 외국 품종에 대한 높은 로열티 지불로 화훼농가 경영에 큰 부담이 되었다. 농촌진흥청에서는 포인세티아 신품종을 육성, 보급하여 로열티 경감과 화훼농가의 안정적인 소득 증대를 위해 노력하고 있다. 포인세티아는 단일성 식물로 보통 자연일장이 줄어드는 10월부터 이듬해 3월 중순까지 꽃눈을 형성한다. 이 시기는 일장단축과 함께 온도도 영향을 미치며 일장조절에 의한 연중출하가 가능하다. 겨울철 출하를 목표로 재배중인 포인세티아는 적정 온도유지, 환기에 의한 습도관리, 병해충 방제 등 환경관리에 특별히 유의해야 한다.

• Korean journal of applied entomology
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• v.1
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• pp.51-53
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• 1962

1. 본시험은 이화곤충방제에 유효하다고 인정된 신살충제를 선정하여 이화곤충에 대한 살충효과의 재확인 및 살포적기를 구명코저 시행하였다. 2. 제일화기에 있어서 Diazinon, Lebaycild, Endrin 및 Folidol은 부화 14일전 처리로서도 부화유충의 식입제로서 유효하였고, 부화유충 식입후일처리구에 있어서도 무처리구에 비하여 유효하였다. 3. 제2화기에 있어 부화 21일전 처리구의 유효성은 Detron=Folidol>$\gamma$-dol>Endrin>Dimecron의 순이었다. 그리고 부화 14일 및 17일전과 부화 2일 및 7일후 처리에 있어서도 $\gamma-dol$을 제한 다음 약제들은 고도의 유효성을 나타내었다. 4. 그러나 약제처리시기 사이에는 유의성이 없었다. 5. 본시험은 1회의 시험성적임으로 동일시험이 수회반복되어 살충효과 및 살포적기가 완전히 구명되었으면 한다.

• Journal of Sericultural and Entomological Science
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• v.34 no.2
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• pp.71-74
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• 1992

우리나라 양잠의 안정적 성장 발전을 위해서는 생산기반의 재정비 및 호당 양잠 규모의 확대가 필요하다고 하는 것은 누구나 다 아는 사실이다. 따라서 이를 위한 생산체계의 획기적인 탈바꿈의 하나로 애누에 공동육을 함으로써 농가에서 누에의 사육기간을 단축하는 것이 시급히 요청된다고 림은 "잠사업이 국제 경쟁력 제고를 위한 기술적 대응방안"에서 주장한 바가 있었다. 1. 전제조건 1) 애누에 공동육이 꼭 이루어져야 한다. 2) 뽕밭 생산성이 저해 받아서는 안 된다. 3) 성력 기계기구 개발 및 지원이 이루어져야 한다. 4) 가장 중요한 것은 잠작안정이다. 5) 각 잠기별 표준관리된 잠종이 공급되어야 한다. 6) 각 수견 시기에 맞추어 고치공판이 이루어져야한다. 2. 누에 사육시간 선정 1) 뽕나무 생리를 감안한 가지뽕 수확법에 따른 누에 사육기간은 춘잠기는 5월 하순부터 6월 중순까지이고 추잠기는 9월 초순부터 하순까지이다. 2) 병충해 방제관리상으로는 하잠 및 초추잠만이 문제점이 있다. 3) 잠작에 따른 사육기간은 춘잠기는 5월 하순부터 6월 중순까지이며 추잠기는 9월 초순부터 중순까지잠작이 양호하다.(중략)