• Applied Biological Chemistry
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• v.47 no.3
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• pp.321-324
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• 2004

Smoke rods were prepared for 2 insecticides and 5 fungicides using powdered rice chaff as a combustible carrier, and their burning characteristics were investigated. The distribution of active ingredient was investigated after the application of the granular smoke generator containing fenarimol in the connected vinyl plastic house growing cucumber. The protective effects of fungicide smoke generators were evaluated against cucumber gray mold (Botrytis cinerea) and tomato late blight (Phytophthora infestans), and compared with commercial wettable powders. Smoke rods containing powdered rice chaff showed high smoking rates of AI that were higher than commercial smoke pellets. The deposition of fenarimol on the ground of vinyl plastic house was $26.2{\pm}7.7\;ng/cm^2$ when averaged from 9 sites, and application uniformity was found. Also, the protective effects of 5 fungicidal smoke rods against plant diseases were so similar to the commercial wettable powders with no phytotoxicity that smoke rod formulations containing rice chaff as a combustible carrier could be used as an effective formulation for pesticides.

• Korean Journal of Environmental Biology
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• v.17 no.2
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• pp.129-138
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• 1999

Chlorinated aromatic compounds are one of the largest groups of environmental pollutants as a result of world-wide distribution by using them as herbicides, insecticides, fungicides, solvents, hydraulic and heat transfer fluids, plasticizers, and intermediates for chemical synthesis. Because of their toxicity, persistence, and bioaccumulation, the compounds contaminated ubiquitously in the biosphere has attracted public concerns in terms of serious influences to wild lives and a human being, such as carcinogenicity, mutagenicity, and disturbance in endocrine systems. The biological recalcitrance of the compounds is caused by the number, type, and position of the chlorine substituents as well as by their aromatic structures. In general, the carbon-halogen bonds increase the recalcitrance by increasing electronegativity of the substituent, so that the dechlorination of the compounds is focused as an important mechanism for biodegradation of chlorinated aromatics, along with the cleavage of aromatic rings. The removal of the chlorine substituents has been known as a key step for degradation of chlorinated aromatic compounds under aerobic condition. This can occur as an initial step via oxygenolytic, reductive, and hydrolytic mechanisms. The studies on the biochemistry and genetics about microbial dechlorination give us the potential informations for microbial degradation of xenobiotics contaminated in natural microcosms. Such investigations might provide biotechnological approaches to solve the environmental contamination, such as designing effective bioremediation systems using genetically engineered microorganisms.

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.14-21
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• 1982

Analytical methods for residues of six N-methylcarbamate insecticides were investigated to compare the minimum detectability, recovery from several crops and feasibility of multiple residue analysis. Those methods studied in this work included spectrophotometry by diazotization and gas chromatography by N-trifluoroacetylation(TFA), pentafluorobenzylether(PFB) and dinitrophenylether (DNP) derivatization. Maximum absorbed wavelength of the diazotized MIPC, XMC, BPMC, propoxur and carbofu ran was around 460 ㎚, while that of carbaryl recorded 510 ㎚. Recovery from brown rice and apple by diazotization method ranged from 80 to 120% and minimum detectable limits were 0.03 to 0.05 ppm in 50 g of the sample. Minimum detectability of PFB derivatives by gas chromatography was superior to TFA and DNP derivatives. DNP derivatives showed the longest retention time among the given derivatives. Recovery from crops by gas chromatographic met hod ranged 74 to 94%, 78 to 93%, and 85 to 99% in brown rice, rice straw and apple, respectively. Limit of detection was 0.01 ppm for TFA, 0.005 ppm for PFB and 0.02 ppm for DNP derivatives in 50 g of the crop samples.

• Korean Journal of Environmental Agriculture
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• v.3 no.1
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• pp.16-21
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• 1984

The present study was aimed to investigate persistence of dichlorvos EC, fenitrothion EC, fenthion EC, and phenthoate EC in and on mulberry leaves with special reference to silkworm mortality and cocoon production under greenhouse condition. The halflives of fenitrothion, fenthion, and phenthoate in and on mulberry leaves were ranged from two to three days, while that of dichlorvos was less than 9 hours. The insecticide residues in and on mulberry leaves persisted longer in spring cropping season than in autumn cropping season. Elapsed periods from last application of each insecticide to leaf harvest for silkworm feed and maximum residue limits for safe cocoon production as well as relations between insecticide residues in and on mulberry leaves and silkworm mortality were produced.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.87-94
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• 2007

Pyrethroid insecticide have widely been used for agricultural sector and residential environments. To assess the exposure of insecticide which is absorbed through skin the analysis of urinary metabolite is essential. At present, the urinary 3-PBA was analyzed using liquid-phase extraction. But LPE have many limitations, such as long pre-treatment time and low recovery. So, this study was conducted to determine the optimum conditions for analysing 3-PBA in urine using solid phase extraction. Furthermore, this study intend to investigate the relation of concentrations of pyrethroid, deltamethrin in air and 3-PBA in urine. The optimum condition for hydrolysis was found to be done with hydrochloric acid for one hour. The recovery rates of 3-PBA were $84.6%{\pm}1.2%$, $54.8{\pm}0.9%$, $99.8{\pm}1.2%$ with XAD-2, XAD-7, XAD-16 using as the aborbents and acetone as eluents respectively. But acetonitrle and methanol gave low recovery rate and methyl cellosolve could not elute the compound. The amount of acetone for elution were 6mL, 9mL, 3mL for XAD-2, XAD-7, XAD-16 as absorbents respectively. The non-absorbed rates was $0.8{\pm}0.5%$, and $0.7{\pm}0.3%$ under XAD-16, mesh size 140-200, amount of resin 1.4g and the flow rate of eluent was 0.1mL/min. In the concentration process, we obtained 11 times higher concentration of material. The amounts of urinary 3-PBA were. The LODs of 3-PBA and deltamethrin were 0.004 mg/L, 0.038 mg/L, respectively. The further research of minute monitoring which include spray pattern, environmental condition is needed And more research about the relation between total pyrethroid exposure and urinary various metabolite are also necessary.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.134-140
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• 2008

The data on pesticide poisoning death toll during 2000-2005 was obtained from Korean National Statistical Office and analysed to find out any precautionary measures against pesticide poisonings. Pesticide poisoning death toll showed slightly increasing trend with year up to about 3500 in 2005. Most of the pesticide poisoning death cases were intentional self-poisoning accounting for more than 80% of total pesticide poisoning death. The pesticide most often implicated in poisoning death were paraquat dichloride, a non-selective herbicide and organophosphate/carbamate insecticides. The regional distribution of pesticide poisoning death showed urban 21.6% and rural area 78.4%. As for the occupation of the dead, agricultural, forestry and fishery workers accounted for 27.4% and non-agricultural workers was 72.6% of pesticide poisoning death. Therefore, government need to take some precautionary measures to reduce the number of pesticide poisoning cases. It is strongly recommended that pesticide regulatory authorities encourage and train the agricultural workers to use safe storage boxes and enforce strict regulation for the prevention for the prevention of highly toxic pesticides sales to non-agricultural workers.

• Korean journal of applied entomology
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• v.30 no.1
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• pp.10-17
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• 1991

Cuticular penetration and detoxication as mechanisms of resistance to the carbamate insecticides in fenobucarb-selected($R_{f}$) and carbofuran-selected($R_{c}$) strains of the brown planthopper (N. lugens Stal) were investigated. Rates of penetration were not significantly different in the susceptible and resistant strains. However, total amount of excretion of the $R_{f}$ and $R_{c}$ strains were much larger than that of the susceptible strain. Fenovucarb and carbofuran were in vivo metabolizd much faster in the $R_{f}$ strain than in the susceptible strain. OSBP(o-sec-butyl phenol) and 3-ketocarbofuran phenol were invitro the major metabolites of fenobucarb and carbofuran in the brown planthopper, respectively. Total amount of the two major metabolites were produced abotu 2 times larger in the $R_{f}$ and $R_{c}$ strains compared to the susceptible strain. OSBP and 3-ketocarbofuran phenol were not so toxic to the brown planthopper ($LD_{50}$ >100 $\mu\textrm{g}$/g hopper). Based on our data, detoxication plays a large role in resistance to fenobucarb and carbofuran in the resistant strain of BPH, although several resistance factors maybe involved.

• Korean journal of applied entomology
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• v.13 no.1 s.18
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• pp.25-31
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• 1974

This survey was aimed to accumulate basic data of aphid population at the Horticultural Experiment Station at Suweon. The yellow pan traps were setted at five locations (Fig.1.), and ran from May 1 to October 31. 1970. About one hundred and twenty species of aphids were trapped, including 24 species of plant vims vectors. Of these, dominant species were as follows: (Asterisk shows virus vector) Aphid species No. of catches * Aphis spiraecola PATCH 2,635, * Aphis craccivora KOCH 2,377, * Myzus persicae SULXER 2,111, Capitophorus hippophaes javanicus H.R. LAMBERS 2,051, Anoecia fulviabdominalis SASAKI 1,480, * Aphis gossypii GLOVER 867, * Macrosiphum avenae FABRICIUS 859, Cervaphis quercus TAKAHASHI 692, * Lipaphis erysimi KALTENBACH 645, Pleotrichophorus chrysanthemi THEOBALD 489, The above 10 species consisted $76.5\%$ of total catches and the 24 vector species consisted $55.5\%$. The curve of the seasonal occurrence of flying aphids at Horticultural Experiment Station shows bimodal, typical for the temperate region. The total number of trapped aphids at the Station from May to September, 1970, were less than that of average yearly catches at the College of Agriculture from 1967 to 1970. Thi, low numbers at Horticultural Experiment Station may attribute to the frequent spraying of insecticides from Spring to Summer on growing crops there. But the aphids population increase suddenly in the middle of October. This might be resulted from cease of insecticide applications and migration of aphids from summer host to winter host plants.

• Korean Journal of Agricultural Science
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• v.43 no.3
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• pp.346-352
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• 2016

This study was conducted to obtain the correlation between the plant surface spray adhesion amount of pesticides and the pest control effect. The linearity of the standard curves of dinotefuran and thiodicarb was $R^2=0.9999$, and recovery was between 70% to 120% which was satisfactory for insecticide residue analyses. The pest control effect was evaluated by assessing the number of apple leafminers (Phyllonorycter ringoniella, Gracillariidae, Lepidoptera) captured by sex pheromone traps from late June to late September in 2015. For the adhesion amount, dinotefuran recovered from trap A and B, respectively were $47{\mu}g/50cm^2$ and $23{\mu}g/50cm^2$, which can be characterized as a very low adhesion amount in comparison to the average adhesion amount of $81{\mu}g/50cm^2$ in the field. In case of thiodicarb, $691{\mu}g/50cm^2$ and $71{\mu}g/50cm^2$ were recovered from trap A and B, respectively, and the average amount in the field is $325{\mu}g/50cm^2$. These results showed close correlation with the insect population captured by trap A and B. The numbers of insects captured by trap A and B between the end of July and late August were similar. After spraying thiodicarb on August 28, the number of apple leafminers captured by trap B is bigger than that of trap A. It appears that pest occurrence tended to be high at low adhesion amounts of the active ingredient. Therefore, in order to obtain an optimal control effect, it is suggested that uniform application of insecticides is critical instead of relying on the amount of insecticide applied in the field.

• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.271-276
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• 1983

In field studies, the insecticides carbofuran(Furadan 3G) and diazion(3G) at the rate of 1,8 kg a.i./ha as a single side-furrowing treatment from March 13 to April 10(7 to 10 days intervals) were evaluated in terms of the control effects to the onion maggots(Hylemyia antique Meigen) and some phytotonic effects to the garlic plants. The treatments with carbofuran were significantly more effective in onion maggot control than the treatment with diazinon and untreated, and the earlier treatments the better control effects were obtained. Phytotonic effects only with carbofuran on garlic plants were of served as increases ranged $16.5\~23.2\%$ in plant heights, $22.0\~32.0\%$ in stem diameters and $15.5\~22.8\%$ in bulb diameters compared to the untreated. The greatest yield of garlics was resulted in the plots of Match-13 treatments with carbofuran, ca. 10,700kg/ha in the carbofuran treatment, ca. 5637kg/ha in the diazinon treatment and ca. 4728kg/ha in the untreated plots. The magnitude of yield increase of garlics in the plots treated with carbofuran was attributable to positively stimulate the growth response of garlic plants as well as the control effects to onion maggots.