• Korean journal of applied entomology
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• v.32 no.1
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• pp.24-29
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• 1993

Experiments were conducted to study effects of different bioassay methods on toxicity to the German cockroach (Blattella germanica L.) ith six insecticides. For male adults, by dry film method, the {TEX}$LC_{50}${/TEX} value of chlorpyrifos. fenvalerate, propoxur, permethin, DDVP, and hydramethylnon was 1.79, 1.87, 3.04, 4.37, 32.72, and 270.81 ppm, respectively and the same tendency was shown in the female. For male adults, by topical micro-application method, the {TEX}$LD_{50}${/TEX} value of DDVP and fenvalerate, chlorpyrifls, permethrin, propoxur, hydramethylnon was 2.63, 3.79, 4.51, 6.73, 44.99 $\mu\textrm{g}$/g, respectively and the same tendency was shown in the female. From the diet toxicity method against male adults, the CT value (Concentration%$\times${TEX}$LT_{50}${/TEX}) showed that chlorpyrifos was rapid effective and hydramethylnon was residual effective.

• Korean journal of applied entomology
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• v.32 no.2
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• pp.129-133
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• 1993

The German cockroach (Blattella germanical L.) populations were successively selected with chlorpyrifos and permethrin for xis generations. The resulting resistant strains, $R_{chlorpyrifos}$(Rc) and $R_{permethrin}$(Rp) were observed resistant development and the cross-resistance. The result indicated that the values of $LC_{50}$ were increased 3.32 and 2.10 times from the susceptible strain, respectively. In the Rc strains, the values of the $LC_{50}$ of fenvalerate, propoxur, permethrin were to 3.89, 2.97, and 1.31 times higher than that of the suseptible, respectively. In the Rp strains, the values of the $LC_{50}$ of fenvalerate, chlorpyrifos, and propoxur showed 5.23, 1.42, and 1.80 times cross-resistance.

• Korean Journal of Veterinary Service
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• v.25 no.1
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• pp.23-29
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• 2002

A method was developed to separate, detect and qualify aldicarb, bendiocarb, carbaryl, carbofuran, ethiofencarb, methomyl, methiocarb, propoxur in meats and fruits. Experimental beef and fork samples were fortified with 0.05mg/kg of carbamate pesticides for analysis. Carbamate-detected pear by HPLC fluorescence detector(HPLC/FLS) are extracted with acetonitril and refined by solid phase extraction(SPE) filled with aminopropyl-bonded silca, In the following step, the injected materials into LC/MS are analyzed to result in the fact that bendiocarb, carbaryl, carbofuran, ethiofencarb, methomyl, methiocarb, propoxur presents several sorts of fraction ions following with; [M+H]$^{+}$, [M+Na]$^{+}$,［M-CONH$CH_3$]$^{+}$, [M-OCONH$CH_3$]$^{+}$. In addition, ethiofencarb presents [M-SCH$_2$$CH_3$]$^{+}$ ion distinctive and aldicarb presents [M+Na]$^{+}$ and [M-OCONH$CH_3$]$^{+}$ ion which is the most decisive fraction ion for pesticides such as bendiocarb, carbaryl, carbofuran, ethiofencarb, methiocarb, methomyl, propoxur excluding [M+H]$^{+}$ ion. However, [M-OCONH$CH_3$]$^{+}$ and [M-OCONH$CH_3$]$^{+}$ fraction ion charactering carbamate pesticides are detected most efficiently with fragment voltage 50ev. As a result, for rluantitative analysis, [M+Na]$^{+}$ ion is the most decisive ion for detection of aldicarb and [M+H]$^{+}$ ion is the most decisive fraction ion for Pesticides such as bendiocarb, carbaryl, carbofuran, ethiofencarb, methiocarb, methomyl, propoxur. Carbaryl-detected pear by HPLC/FLS are analyzed by L/MS and the result shows that [M+H]$^{+}$ and [M-CONH$CH_3$]$^{+}$ ions charactering carbaryl are detected.ering carbaryl are detected.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.4
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• pp.375-385
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• 1987

This study was carried out to investigate the effects of pesticides on soil respiration, microflora and enzymes in loam soil, and on pathogenic microorganisms in continuous pepper cropping soil. The results are summarized as follows. No significant effect of pesticides on soil respiration was shown, with the exception of propoxur which slightly increased at $10{\mu}g\;g^{-1}$ treatment. When pesticides were treated, the amount of soil microorganisms generally decreased at the early stage of incubation and the number of microflora was much more decreased at 60-day incubation. When pesticides were treated, the amount of soil enzyme activity was inhibited at the early stage of incubation and gradually recovered at the last stage of incubation. The amount of polygalacturonase activity was increased at the 20-and 30-day incubation in propoxur treatment plot. The amount of ${\beta}$-glucosidase and dehydrogenase activity was increased at 20-and 60-day incubation in carbofuran and acephate treatment plot. The amount of phosphatase activity was increased at 60-day incubation in propoxur and isoprocarb treatment plot. The amount of Fusarium generally decreased in continuous pepper cropping soil, with the exception of isoprocarb and acephate treatment plot which significantly increased. The amount of Pythium increased at 60-day incubation with the exception of captan treatment plot which significantly decreased.

• Journal of Environmental Science International
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• v.11 no.4
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• pp.391-397
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• 2002

This study was carried out with the inhibition of the cholinesterase activity by carbamate insecticides in the chicken in vivo and in vitro. The optimum pH of cholinesterase was 8.0. The cholinesterase activity used the acetylcholin as substrate in plasma was 24.6 $\mu$mol/min/g protein. After oral administration with 0.32 mg/kg of BPMC as carbamate pesticide, the cholinesterase activity was inhibited to 60% of control after 15min in vivo. Then the recovery of cholinesterase activity followed to 97% of control after 12hr. I$_{50}$, such as concentration required for 50% inhibition of enzyme activity, of phenyl N-methylcarbamate were 329 $\mu\textrm{g}$/$\ell$ of XMC, 214 $\mu\textrm{g}$/$\ell$ of metolcarb, 111 $\mu\textrm{g}$/$\ell$ of BPMC, 107 $\mu\textrm{g}$/$\ell$ of propoxur and 104 $\mu\textrm{g}$/$\ell$ of isoprocarb. I$_{50}$ of aromatic N-methylcarbamate were 280 $\mu\textrm{g}$/$\ell$ of carbaryl and 114 $\mu\textrm{g}$/$\ell$ carbofuran.ran.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.266-271
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• 2006

This study was monitored for 14 pesticide residues in agricultural products for the army, such as fruit vegetables(pepper, cucumber, pumpkin, melon and water melon), leafy vegetables(Korean cabbage, spinach, lettuce, crown daisy, cabbage, green onion), mushrooms(agaric, p'yogo), and bean sprouts produced in Kyunggi-do and Inchon-City. From January to December 2005, ten carbamate pesticides in 356 samples were analyzed by HPLC. One kind of pesticide was detected in 8 samples of detection rate (2.53%), and two pesticides were in one sample of detection rate(0.27%). Aldicarb, bendiocarb, fenobucarb, methiocarb, isoprocarb, and propoxur were not found in all samples. Detection rates of pesticides were 0.84% for methomyl, 0.56% for carbofuran, 0.56% for ethiofencarb, and 0.28% for carbayl. Dectection ranges of pesticides were from 0.01 to 2.9 mg/kg for ethiofencarb, from 0.1 to 0.23 mg/kg for methomyl, from 0.20 to 0.24 mg/kg for carbofuran, and 0.01 mg/kg for carbaryl, respectively. Consequently, detection levels of all pesticides in samples were less than the maximum residue limits(MRLs) in Korea representing that all agricultural products for the army were safe.

• Applied Biological Chemistry
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• v.29 no.4
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• pp.407-415
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• 1986

To obtain informations on the development of the combined granular pesticides for the simultaneous control of rice insect pests and diseases which often occur at the same time or in overlapping experiments were carried out on twelve mixture pesticides of granular type formulated by extrusion method with two fungicides and three insecticides. Each of 12 mixtures was tested for physico-chemical properties and efficacy against to rice leaf blast and brown planthoppers under the laboratory conditions. All of the mixture pesticides showed acceptable physico chemical properties as granular formulation. Most of the compounds in mixture pesticides showed a tendency to have lower stabilities than those of pesticide alone, therefore, it was necessary to add stabilizer in formulation process. Isoprothiolane combinations were found very effective against leaf blast but their control effects were similar to that of isoprothiolane alone due to its high efficacy, while probenazole-carbofuran combinations showed synergistic effects for the control of leaf blast. All of the combinations showed synergistic effects to brown planthoppers. But fenthion and 3% propoxur combinations resulted comparatively low efficacies. In the consideration of their physico-chemical properties and efficacies to rice pests, carbofuran and 6% propoxur combinations were promising combined granular pesticides for the simultaneous control of leaf blast and brown planthoppers, while fenthion and 3% propoxur combinations were not available because of their low efficacies for brown planthoppers.

• 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 applied entomology
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• v.33 no.3
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• pp.166-172
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• 1994

This study was conducted to investigate the resistance development and cross-res~stance of house fly (Musco dornestica L.) selected with chlorpyrifos, dichlorvos and permethrin for 11 generations to various p u p s of insectiodes. The resistance ratio (RR) of the chlorpyrifos-selected (Q), the d~chlorvos- selected (&) a d the permethrin-selected (R,) stmlns were 42 0. 38 and 187 tlrnes in female. and 42.0, 4 1 and 16.4 time; in male from the susceptible strain, respectively. The Rc strain showed highest cross-resistance to permethlin among the insectic~des tested: RR=7.5 and 9.6 tunes in female and male, respectively, whereas negatively correlated cross-resistance to propoxur was observed. High cross-res~atance to chlorpyrifos were produced for female (RR= 13.3) and male (RR=15.9) of Rd strain, and female (RR=8.7) and male (RR= 9 7) of R, strain. respectively

• Journal of Environmental Science International
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• v.7 no.1
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• pp.52-56
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• 1998

The effects of organophosphorus and carbamate pesticides were examined inhibition of the acetylcholinesterase activity in the chicken brain with enzyme-inhibition methods. The acetylcholinesterase activity in chicken brain determined by the Ellman method was 167 mmol/min/g protein. The optimum pH of acetycholinesterase was 8.2. $pl_{50}$ of acetycholinesterase by some organophosphorus were 3.80M of phosphorodlthioate, 4.04M of phosphorothioate, 6.33M of phosphate, and 6.60M of phosphrothiolate. pluto of acetycholinesterase by some carbamates were 5.1 OM of XMC, 5. 90M of carbofuran, 6.16M of isoprocarb, 6.30M of carbaryl, 6.47M of BPMC, and 6.77M of propoxur. pluto of carbamates selected was similar to that of phosphorothioate and phosphate organophosphates.