• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.369-374
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• 2016

Bacillus velezensis YP2 inhibited the mycelial growth of several plant pathogens including Cercespora spp., Septoria sp., Phoma sp., Botrytis cinerea and Sclerotinia scleotiorum occurring in leafy vegetables. Control efficacy for powdery mildew caused by Erysiphe cruciferarm on red leaf mustard and cheong mustard by treatment of spraying with 10-fold diluted Luria-Bertani (LB) broth of B. velezensis YP2 was 91.8% and 80.9%, respectively. When B. velezensis YP2 was treated four times with five-day interval, three times at seven-day interval and two times at ten day interval in the greenhouse test, the control effect of red leaf mustard powdery mildew was 70.6%, 65.0% and 40.9%, respectively. Also B. velezensis YP2 could promote the seed germination and plant growth of led leaf mustard. The results showed that the culture broth of B. velezensis YP2 was very effective to control the powdery mildew of leaf mustard.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.297-301
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• 2009

Hydrogen peroxide, which is used in various crops as an oxidizer to improve high temperature adaptation, was evaluated on the effects on productivity and disease incidence in paprika (Capsicum annuum L.) by periodic leaf spray at summer. Hydrogen peroxide treatment not only increased the leaf thickness and SPAD (chlorophyll content) but also the fruit set numbers per plant by 2. Hydrogen peroxide content increase in leaf resulted in increase of catalase and peroxidase activities, and the powdery mildew disease (Leveillula taurica) was also suppressed by the treatment. Transpiration was improved by the reduced leaf stomata resistance in the hydrogen peroxide treatment. Therefore, hydrogen peroxide leaf spray is recommended for improvement of summer productivity in paprika.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.488-493
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• 1996

As a first step of pesticide runoff studies, runoff losses of captafol were measured under natural rainfall conditions in apple orchard area. The maximum concentration of captafol was 180 ppb at 5 th sampling period when the rainfall occurred within 24 hours after captafol was applied, and the concentration of samples from other periods was below than 20 ppb. Total runoff loss of captafol was below 0.1%. About 10 fold of dilution factor was observed at the merging point with stream near outlet from orchard and about 50 fold was observed at the next merging point which is located further down. Therefore, captafol will not harm the aquatic organisms due to dilution factor$(10{\sim}50\;fold)$ and rapid hydrolytic degradation rate even when it was run off into a stream nearby.

• Journal of Environmental Health Sciences
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• v.27 no.2
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• pp.37-42
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• 2001

Zebrafish(Brachdanio rerio)를 실험어류로 하여 methidathion 과 phosalone의 생물농축계수(bioconcentration factor : BCF)와 배설속도상수 (depuration rate constant) 및 LC$_{50}$를 측정하였다. Methidathion의 24, 48, 72, 96시간 LC$_{50}$는 각각 28.34, 35.98, 24.43, 22.03 mg/$\ell$로 측정되었다. Methidathion 0.22 mg/$\ell$(고농도)와 0.022 mg/$\ell$(저농도)에서 어류 체내에서의 농축정도는 두 농도군에서 각각 12시간 이후에 정류상태에 도달하여 72시간동안 거의 일정하였고, BCF값도 12시간에서 72시간 사이에 고농도와 저농도에서 8.72(n=4)와 11.25(n=4)로 조사되었다. 배설속도상수는 고농도와 저농도에서 6시간 이내에 모두 배설되어 배설속도상수를 구할 수 없었다. Phosalone의 24, 48, 72, 96시간 LC$_{50}$는 각각 3.76, 2.43, 1.86, 1.05 mg/$\ell$로 측정되었다. Zebrafish 체내에서의 농축정도와 BCF값은 고농도(0.01 mg/$\ell$)에서 12시간 이후에 정류상태에 도달하여 72시간동안 거의 일정하였고, BCF값은 12시간에서 72시간 사이에 48.88(n=4)로 측정되었다. 저농도(0.001 mg/$\ell$)에서는 실험 전기간동안 zebrafish 체내에서 phosalone이 검출되지 않아 BCF값을 산출할 수 없었다. Zebrafish 체내에서 phosalone(고농도)의 배설속도상수와 반감기를 구하기 위하여 6,12시간의 배설실험 결과 각각 0.17$hr^{-1}$과 4.01 시간이었다. Methidathion과 phosalone의 BCF값은 phosalone이 methidathion 보다 약 5배 정도 높게 나타났으며, 농약의 배설속도는 phosalone이 methidathion보다 빨랐다.

• Korean journal of applied entomology
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• v.60 no.1
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• pp.145-154
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• 2021

Integrated pest management system in Korean apple has significantly advanced for last few decades. However harmful effects of pesticides threats the ecosystem services of natural enemies and pollinators. Apple require cross-pollination and Insect pollination with diversity and abundance is one of the keys to profitable apple production in quantity and quality as well. Thus crop protection tools are to be administered in harmony to meet the pest suppression and protection of beneficial organisms such as natural enemies and pollinators. Adding onto the established IPM system, integrated pollinator-pest management (IPPM) concept is proposed as the future direction of apple IPM. For this, ecological enginnering of creating habitats for pollinators, landscape management and agroecosytem diversification as well as selective soft pesticide uses on time guided by pest monitoring and phenologyand targeted delivery are further proposed. Recent shift of agroecosystem from climate change and new pest outbreaks require new paradigm of pest management for sustainable agricultural production.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.269-277
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• 2011

Recent outbreak of new diseases and pests which were introduced from abroad, seriously hampered both quality and safety of paprika fruits. This study has been carried out to aid an establishment of guideline for safe use of pesticides and reduction of their residues on paprika. Systemic fungicides boscalid and pyraclostrobin of either mixed (a.i.; 13.6+6.8%) or single (a.i.; 47 and 18.8%, respectively) water dispersible granule formulation(WG) products were sprayed with recommended or double dosage on paprika grown in green house at March and June. To draw pre-harvest residue limit, residues of each fungicide were analyzed from fruits collected eight times from 18 to 1 day pre-harvest. The biological half-lives of both boscalid and pyraclostrobin in mixed formulation in March and June were slightly shorter than those of single formulation which ranged from 14.4 to 20.1 days. Residue levels of both fungicides of single formulation in fruits in June were about one lower compared to those in March. However, application of double dosage frequently exceeded MRLs from fruits grown both seasons. These results showed that residue levels on fruits persisted longer period of time, more than two weeks, and so the case applied in winter season. The dissipation of fungicides on leaves and fruits was compared. The distribution of both fungicides in leaves was 20-200 times higher than that of fruits and persisted up to 18 days of pre-harvest period at the concentration of 10-40 ${\mu}g\;g^{-1}$. This study indicated that the mixed formulation product exhibited low residues in fruits, but high and long enough to pathogen growth in leaves.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.463-470
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• 2011

This study was carried out to survey the residual characteristic of chlorpyrifos and estimate their residues in squash before harvest. The pesticide was sprayed onto the crop at the recommended and its double rates 10 days before the prearranged harvest and sampling was done at 0, 2, 3, 5, 6, 7 and 10 days after spraying. The amounts of the chlorpyrifos residue in the crop was analyzed by chromatographic method. Limit of detection (LOD) of chlorpyrifos was 0.005 mg/kg and its recovery ranged from 95.21 to 102.69%. The initial concentration of chlorpyrifos sprayed with recommended dose exceeded its MRL of 0.1 mg/kg but its concentration was less than its MRL 10 days after application. However its concentration in case of the double dose was over its MRL both immediately and 10 days after application. Biological half-lives of chlorpyrifos sprayed onto squash was 2.5 and 2.9 days at the recommended and double doses, respectively. Ten days later, the residual concentration of chlorpyrifos in squash was decreased substantially. The concentration of chlorpyrifos was estimated in squash at the given day using its regression equations. The estimated concentration of chlorpyrifos in case of application with recommended dose was below its MRL at 10 days after application but its concentration in case of application with double dose was over its MRL at 10 days of the prearranged harvest. The rate of the estimated daily intake (EDI) of chlorpyrifos to its acceptable daily intake (ADI) was 282% right after application but it decreased to less than 18% at 10 days of the prearranged harvest.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.273-282
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• 2011

This study established hazards which may cause risk to human at farm during cultivation stage of paprika. Samples of plants (paprika, leaf, stem), cultivation environments (water, soil), personal hygiene (hand, glove, clothes), work utensils (carpet, basket, box) and airborne bacteria were collected from three paprika farms (A, B, C) located in Western Gyeongnam, Korea. The collected samples were assessed for biological (sanitary indications and major foodborne pathogens), chemical (heavy metals, pesticide residues) and physical hazards. In biological hazards, total bacteria and coliform were detected at the levels of 1.9~6.6 and 0.0~4.610g CFU/g, leaf, mL, hand or 100 $cm^2$, while Escherichia coli was not detected in all samples. In major pathogens, only Bacillus cereus were detected at levels of ${\leq}$ 1.5 log CFU/g, mL, hand or 100 $cm^2$, while Staphylococuus aureus, Listeria monocytogenes, E. coli O157 and Salmonella spp. were not detected in all samples. Heavy metal and pesticide residue as chemical hazards were detected at levels below the regulation limit, physical hazard factors, such as insects, pieces of metal and glasses, were also found in paprika farms. Proper management is needed to prevent biological hazards due to cross-contamination while physical and chemical hazards were appropriate GAP criteria.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.48-52
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• 2005

Six stains of plant growth promoting rhizobacteria were selected through germinating seed assay and root colonization assay. Among them, SKU-78 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 60% reduction of bacterial wilt disease compared with the control. It was suggested that SKU-78 strain activated the host defense systems in plants, based on lack of direct antibiosis against pathogen. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, SKU-78 stain was identified as Bacillus sp. SKU-78.

• 월간산업보건
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• s.247
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• pp.16-19
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• 2008

파라티온(Parathion)은 폭넓고 다방면으로 사용되는 유기 인계 해충 진드기의 살충제이다. 파라티온의 첫 번째 생물학적 반응은 콜린에스테라아제 효소의 활성도 저감이다. 파라티온의 다양한 수준의 동물 노출 실험 결과, 경구 투여량 0.5-6 mg/kg 수준에서 악영향이 관찰되었다. 인간의 경우 파라티온 0.1 mg/kg 이하 수준에서는 RBC 콜린에스테라아제 효소의 활성도 감소가 나타나지 않았다. $0.2-0.8\;mg/m^3$의 작업장 노출 수준에서는 RBC 콜린에스테라아제 효소의 감소가 관찰되었다. 본 연구 결과에 근거하여 흡입 노출농도 $0.35\;mg/m^3$에 해당되는 0.05 mg/kg 이하 용량에서는 파라티온과 관련한 건강상의 생물학적 장애 증상이 유발되지 않았다. 따라서 흡입성 에어로졸과 증기상 형태로 $0.05\;mg/m^3$의 TLV-TWA가 파라티온의 작업장 노출기준으로 권고되었다. 이 노출기준은 부교감 신경의 이상과 다른 생물학적 장애 증상을 예방하는 목적에서 설정되었다. 이 수치는 인간을 대상으로 한 연구에서 얻어진 NOAEL로부터 근거를 둔 것이고, 작업자들의 RBC 콜린에스테라아제 효소의 활성도 저하를 방지하는 용량에 해당되는 것으로 예상된다. 이러한 접근은 RBC 콜린에스테라아제 효소의 억제가 단독 사용자에게서는 나타나지 않는다는 것을 확인하는데 이용되는 Biological Exposure Index의 활용과 일치된다. 인간에게 있어 파라티온 피부노출이 죽음까지도 이를 수 있다는 임상적 증세와 연관되어 있기 때문에 피부경고주석이 권고되었다. 쥐들을 대상으로 한 사료 공급 연구들에서 파라티온의 노출을 통한 명확한 종양의 발생 증가가 관찰되지 않아 비발암성 물질(A4)로 설정하였다. 파라티온의 TLV-STEL과 SEN notation을 설정하기에는 아직 충분한 데이터가 확보되어 있지 않고 있으며 파라티온의 작업 노출 모니터링에 대한 자세한 정보를 얻으려면 아세털콜린에스터라제 억제 농약의 BEI 문서들을 참고하는 것이 필요하다.