• 한국환경농학회지
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• 제37권2호
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• pp.87-96
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• 2018

BACKGROUND: The vigorous shoot growth in upper part of apple tree canopy leads to poor fruit quality and flower bud formation in lower part of canopy. So, this study was conducted to develop the proper control method about the shoot growth in upper part of apple tree canopy. METHODS AND RESULTS: Trunks of 'Fuji'/M9 apple trees were cut (back pruned) to 2.5 m in tree height on 11 February (dormant) or 12 April (full bloom). Naphthalene acetic acid (NAA) was applied at 2.0% to cut surface when trunk was pruned. Prohexadione-calcium (Pro-Ca) was sprayed at 250 mg/L above 2.0 m in tree height at 23 April (petal fall). The NAA or Pro-Ca application after trunk was pruned at dormant (TR-2 and TR-3) significantly reduced shoot growth in upper part of canopy compared with the control (tree was only pruned at dormant, TR-1), but the percent of shoots showing the secondary growth of TR-3 was higher over 2 times than that of TR-2. The reduction of shoot growth in upper part of canopy by TR-2 and TR-3 increased the fruit red color from the lower part in the treating year and blooming of the lower part in the following year. CONCLUSION: Applying 2.0% NAA to cut surface of pruned apple trunk at dormant was the most effective way for stabilization of the tree vigor in upper part of the canopy in a high density apple orchard.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권1호
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• pp.61-66
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• 2004

Bacillus thuringiensis 656-3 which was isolated from a soil sample of mushroom house and showed high toxicity to mushroom flies, Lycoliella mali and Coboldia fuscipes, was surveyed for insecticidal effect in the oyster mushroom house.3. thutingiensis 656-3 was mass-cultured in the fermenter containing soybean cake(2%) and wheat bran (2%) as media source. Semi-for-mutation of B. thuringiensis 656-3 was performed with metamorphic starch only. When the formulation suspension containing $5{\times}{10^7}$ cfu was sprayed on the mushroom in mushroom house, the insecticidal effect of B. thuringiensis 656-3 to mushroom flies,1. mali and C. fuscipes, was maintained over 90% by the fifth day after starting spraying. The yield of oyster mushroom house with B. thuringiensis 656-3 was significantly increased compared to control. B. thuringiensis 656-3 represents a powerful biological insecticide for the control of mushroom flies.

• Journal of Advanced Marine Engineering and Technology
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• 제30권1호
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• pp.93-101
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• 2006

This research makes a new attempt to apply the activated seawater by electrolysis in the development of two-stage wet scrubber system to control the exhaust gas of large marine diesel engines. First, with using only seawater that is naturally alkaline (pH typically around 8.1). the $SO_2\;and\;SO_3$ are absorbed by relatively high solubility compared to other components of exhaust pollutants, and PM (Particulate Matter) is removed through direct contact with sprayed seawater droplets. Besides, the electrolyzed alkaline seawater by electrolysis, which contains mainly NaOH together with alkali metal ions $(i.e.\;Na^+,\;Mg^{2+},\;Ca^{2+})$, is used as the absorption medium of NOx and $CO_2$. Especially, to increase NOx absorption rate into the alkaline seawater. nitric oxide (NO) is adequately oxidized to nitrogen dioxide $(NO_2)$ in the acidic seawater, which means both volume fractions are adjusted to identical proportion. The results found that the strong acidic seawater was a valid oxidizer from NO to $NO_2$ and the strong alkaline seawater was effective in $CO_2$ absorption In the scrubber test, the SOx reduction of nearly $100\%$ could be achieved and also led to a sufficientPM reduction. Hence, the author believes that applying seawater and its electrolyte would bring the marine air pollution control system to an economical measure. Additionally it is well known that NOx and SOx concentration has a considerable influence on the $N_2O$ emission of green house gas. Although the $N_2O$ concentration exhausted from diesel engines is not as high, the green house gas effect is around 300 times greater than an equivalent volume of $CO_2$. Therefore, we investigated the $N_2O$ removal efficiency with using the electrolyzed seawater too. Finally this research would also plan to treat the effluent by applying electro-dialysis and electro-flotation technique s in the future.

• The Plant Pathology Journal
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• 제33권5호
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• pp.450-457
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• 2017

Scabs caused by Venturia carpophila greatly reduce the quality of the fruits of the Japanese apricot (Prunus mume) when the disease is not properly managed. The disease produces a superficial blemish that is unlikely to affect the overall yield of processed fruit, but reduce the value of fruit intended for the fresh market. Incidence rates of scab at sprayed and unsprayed orchards range from 0% to 21.5% and from 30.2% to 100%, respectively, in the major cultivation regions of Jeonnam Province during the growing season of 2009. The trends in disease progress were quite similar, regardless of regions, and cultivar Namgo was relatively less damaged by scab compared to cultivar Cheonmae among the tested Japanese apricot cultivars. The fruits on branches 1.5 m above the infected Japanese apricot trees and the stem-end parts of the infected fruits were more severely damaged by scabs, possibly because of rain and run-off facilitate dissemination of conidia of V. carpophila and subsequent infection of the fruits or branches. The conidia of V. carpophila were dispersed from March 24 to April 26 in 2010, and more conidia were dispersed from 2-year-old branches than 1-year-old branches. Since the control efficacies were higher than 90% after more than two applications of Trifloxystrobin WG at 10-day-intervals from mid April, it is that effective fungicides be applied at least two times at 10-day-intervals from the middle of April to manage scabs of Japanese apricot in orchards.

• The Plant Pathology Journal
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• 제26권1호
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• pp.37-48
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• 2010

This paper describes a web-based information system for plant disease forecast that was developed for crop growers in Gyeonggi-do, Korea. The system generates hourly or daily warnings at the spatial resolution of $240\;m{\times}240\;m$ based on weather data. The system consists of four components including weather data acquisition system, job process system, data storage system, and web service system. The spatial resolution of disease forecast is high enough to estimate daily or hourly infection risks of individual farms, so that farmers can use the forecast information practically in determining if and when fungicides are to be sprayed to control diseases. Currently, forecasting models for blast, sheath blight, and grain rot of rice, and scab and rust of pear are available for the system. As for the spatial interpolation of weather data, the interpolated temperature and relative humidity showed high accuracy as compared with the observed data at the same locations. However, the spatial interpolation of rainfall and leaf wetness events needs to be improved. For rice blast forecasting, 44.5% of infection warnings based on the observed weather data were correctly estimated when the disease forecast was made based on the interpolated weather data. The low accuracy in disease forecast based on the interpolated weather data was mainly due to the failure in estimating leaf wetness events.

• 한국환경농학회지
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• 제5권2호
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• pp.119-129
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• 1986

오리나무잎벌레 방제용으로 항공 살포한 trichlorfon($Dipterex^R$ 혹은 $Dylox^R$)의 환경생태계내 동태를 조사한 결과는 다음과 같다. 1. 슬라이드그라스에서 검출한 trichlorfon으로서 항공 살포시에 농약이 적량으로 살포되었음을 알 수 있었고 살포한 당일에 거의 소실됨을 확인하였다. 음지에 낙하되는 약량은 노지에 비하여 약 1/100에 불과하였다. 2. 수중에서 검출된 trichlorfon은 항공살포에 의한 내수면의 오염이 동물성 플랑크톤류에 영향을 미칠 수 있는 농도임을 확인하였고, 강우에 의한 내수면의 재 오염이 가능함을 관찰하였다. 3. 토양에 잔류한 trichlorfon의 변화양상을 보면 위치에 따라 소실속도의 완급이 다름을 알 수 있었고 슬라이드그라스와는 달리 소실속도가 늦음을 확인하였다. 4. 식물체 엽면에 살포된 농약의 양은 예상 투하량 보다 비교적 적었고 소실 속도는 토양에서와 유사한 양상이었다. 본 연구에서 밝혀진 잔류량의 변화만으로서는 그 소실 형태가 물리적인 확산, 이동에 의해서인지 화학적인광분해, 가수분해 등에 의해서인지는 확실치 않았으므로 차후에 보완적인 연구가 수행되어야 함과 아울러 문제시 되는 수중농도의 생물학적인 영향 연구도 병행되어 야 할 것이다.

• 한국환경농학회지
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• 제17권4호
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• pp.306-311
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• 1998

Effects of soluble silicon and surfactants on the development of powdery mildew of cucumber were tested for environmentally safe powdery mildew control. Tested soluble silicon was potassium silicate$(K_2SiO_3)$ and tested commercial surfactants were Jeonchakje, Silhouette, Kaba, and Tween 20. Tested concentrations were 2, 4, 8, 16mM for the soluble silicon, 0.5 and 1.0% for Tween 20, 0.05 and 0.1% for both Jeonchakje and Kaba, and 0.03 and 0.07% for Silhouette. Water dilutions of tested materials were sprayed on cucumber (Cucumis sativus) leaves once a week for 4 weeks. From 3 days after the second spray, the diseased area and the numbers of fungal colony were measured from the treated leaves for 6 times at 3-4 days interval. Powdery mildew was less severe on treated cucumber compared to distilled water-treated cucumber (check). In all treatments, diseased area index was proportional to the number of the fungal colony. At the end of investigation, there was severe powdery mildew on check cucumbers. Average 30% of a leaf was colonized by powdery mildew fungus and the average number of the fungal colony per leaf reached to more than 70. On the other hand, none of the treated cucumber suffered severe powdery mildew. The treatments including 8 and 16mM of soluble silicon, doubled concentration of Kaba, and 0.5 and 1.0% of Tween 20 showed more than 80% of control effect compared to water-treated cucumber. In addition, no phytotoxicity was found. Potassium silicate and Tween 20 showed the possibility to replace chemical pesticides for the control of powdery mildew.

• 대한한의학회지
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• 제29권2호
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• pp.7-20
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• 2008

Objectives: The purpose of this study wasto examine the effects of Kamijihwang-tang (KJHT) extracts on immune cells and cytokines in ovalbumin (OVA)-induced asthmatic mice. Methods: C57BL/6 mice were injected, inhaled and sprayed with OVA for 12 weeks (four times a week) for asthma induction. Two experimental groups were treated with different concentrations of KJHT (400 mg/kg and 200 mg/kg) extracts and cyclosporine A (10 mg/kg) for the later 8 weeks. At the end of the experiment, the mice lung, PLN and spleen were removed and immune cells were analyzed by flow cytometer, IL-5, IL-13, eotaxin-2, $TNF-{\alpha}$ were analyzed by real-time PCR, serum histamine was analyzed by ELISA kit. Results: $CD3^+$, $CD3e^-/CCR3^+$, $CD3e^+/CD69^+$, $CD4^+/CD25^+$, $B220^+/IgE^+$, and $CD3e^+/DX5^+$ cells in lung, PLN, and spleen of the KJHT group (400 mg/kg) decreased compared with that of the control group. $CD3e^+/CD69^+$, $CD4^+/CD25^+$, and $CD3e^+/DX5^+$ cells in lung, PLN, and spleen of the KJHT group (200 mg/kg), CD3+, $CD3e^-/CCR3^+$ cells in lung and PLN of the KJHT group (200 mg/kg) and $B220^+/IgE^+$ cells in lung and spleen of the KJHT group (200 mg/kg) decreased compared with that of the control group. mRNA expression of IL-5, IL-13, eotaxin-2, and $TNF-{\alpha}$ in lung tissue of the KJHT groups (400 mg/kg and 200 mg/kg) decreased compared with that of the control group. Histamine in serum of the KJHT group (400 mg/kg) decreased compared with that of the control group. Conclusions: These results suggest that KJHT can be utilized effectively in treating asthma because it significantly reduces inflammatory cells and cytokines.

• 한국환경보건학회지
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• 제31권1호
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• pp.15-22
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• 2005

This study was conducted to evaluate air injection mode on stabilization of solid waste in lysimeter. For three lysimeters, one was maintained under anaerobic condition as control, and air was injected into two lysimeters in continuous mode (atmospheric pressure) and intermittent mode (high pressure of 2 bar). Distilled water was sprayed over solid waste in 1.4 l/$m^3$(solid waste)/day, supposing rainfall intensity of 1,200 mm/yr and 30% infiltration. Oxygen in landfill gas was not detected in control lysimeter during operational days. After 30 day-aeration, oxygen concentrations of continuous and intermittent modes were maintained in 14% and 6%, respectively. $COD_{Cr}$ removal efficiencies of continuous and intermittent modes were about 70% and 50%, and BOD5 removal efficiencies were about 80% and 20%, respectively. In view of oxygen supply, and $COD_{Cr}$ and $BOD_5$ removal, continuous air injection mode of atmospheric pressure was more effective than intermittent mode of 2 bar. Settling degree of solid waste in case of two air injection modes was 3 times higher than that of anaerobic condition as control. Considering the above results, it was thought that air injection (especially continuous atmospheric pressure) could improve degradation of solid waste and induce preliminary stabilization in landfill site.

• 생물환경조절학회지
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• 제16권1호
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• pp.21-26
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• 2007

본 연구는 굴 껍데기로 제조한 개미산 칼슘화합물에 몇 가지 활성제를 첨가한 용액 수관살포가 사과 '후지' 과실의 칼슘농도, 과점의 발육 및 품질에 미치는 영향을 구명코자 실시하였다. 굴 껍데기로부터 추출한 칼슘 화합물(Os-CaF, $52.4mg{\cdot}kg^{-1}$)을 수관살포하였을 때 조직으로의 칼슘전이 효과는 무처리에 비하여 잎, 과피 및 과육에서 현저한 증가를 보였다. 그리고 Os-CaF에 활성제를 첨가하여 살포하였을 때 '후지' 과실의 칼슘함량은 증가되었다. 특히, 잎에서는 ascorbic acid, polyvinyl alcohol을, 과피에서는 Ag-colloidal, polyvinyl alcohol을, 과육에서는 ascorbic acid, Ag-colloidal, polyvinyl alcohol을 첨가한 칼슘화합물이 칼슘 흡수량을 현저히 증가시켰다. 칼슘화합물의 농도 및 활성제 종류에 따른 과실품질(과중, 경도, 가용성고형물, 산 함량, 과피색)은 차이가 없었다.