• 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.26 no.3 s.72
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• pp.159-163
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• 1987

The toxicity of the mixture at 1 to 1 ratio among the insecticides, BPMC, carbofuran, diazinon and monocrotophos to the brown planthopper (BPH), Nilaparvata lugens and green leafhopper (GLH), Nephotettix virescens were tested and compared to their toxicities of individual insecticides. Among the mixtures, carbofuran combinations with BPMC and diazinon showed synergistic effect in toxicity to BPH. There was also synergistic action in toxicity with mixture of BPMC plus monocrotophos to GLH. Other combinations were independent in toxic action to both insects.

• Korean journal of applied entomology
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• v.14 no.3 s.24
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• pp.147-153
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• 1975

During 1973 a field experiment was carried out to evaluate effectiveness of the root zone application of insecticides in medical gelatin capsules for control of several rice insect pests and dwarf virus disease. At three days after transplanting the capsules were pushed by hand about 2.5cm into the soil, near roots of Tongil rice plants. At the given day intervals number of leaf-and plant-hoppers on the hills were recorded by direct count, and dead hearts and white heads by stem borers and dwarf virus infected hills were observed in the experiment plots. Finally grain yields were measured. The percentages of dead hearts and white heads in all the plots were too low for evaluating the effectiveness of insecticides against the striped rice borers. Carbofuran of the insecticides tested was relatively effective against green rice leafhopper (Nephotettixcincticeps) and small brown planthopper (Laodelphax striatellus), although small number of insects on the hills were recorded. Relatively small number of white-backed planthopper (Sogatella furcifera) was occured in the BPMC and Diazinon treated plots. BPMC and Carbofuran were highly effective against the brown planthopper (Nilaparvata lugens) to 80 days after treatment. Incidence of dwarf virus disease was least in the plots of Carbofuran treatment. The highest grain yield was recorded in the plots treated with Carbofuran, and it seemed to be related with good protection from the dwarf virus disease and leaf-and plant-hoppers.

• Korean journal of applied entomology
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• v.20 no.4 s.49
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• pp.223-227
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• 1981

These experiments were conducted to investigate the nematicidal effects of the insecticides, Mocap(O-Ethyl-S, S-dipropyl phosphorodithioate), Carbofuran(2,3-Dihydro-2,2-dimethyl benzofuranyl ethyl carbamate), Terbufos (S-tert-buthylthio methyl O,O-diethyl phosphordithioate) and their mixtures (Mocap+carbofuran, Mocap+Terbufos, Carbofuran+Terbufos) on growth of 2year-old ginseng, Panax ginseng C.A. Meyer, and the control of root-knot nematodes. There was no evidence of plant injury from insecticide treatment of ginseng, although the rate of emergence of the treated ginseng was slightly inhibited. The insecticide treatments showed no of-flavor of ginseng plant. Terbufos and Mocap provided heifer confrol of the root-knot nematodes than carbofuran alone and their mixtures. Mixtures of the insecticides showed antagonisitic effect to the root-knot nematodes.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2007.10a
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• pp.82-86
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• 2007

• Korean journal of applied entomology
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• v.20 no.2 s.47
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• pp.112-116
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• 1981

This study was conducted to investigate the seasonal occurrence of aphids and to evaluate their efficacy in the field for the control of some aphids on soybean when Carbofuran, Disulfoton and Ortran were applied infurrow at the planting time in 1976. Foxglove aphid (Aulacorthum solani) and soybean aphid (Aphis glycines) were dominat species in soybean field and there were two peaks in the year. The patterns of occurence of aphids were different between in field and yellow-pan. Carbofuran and Disulfoton showed a good effect for the control of aphids but Ortran was less effective.

• 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.

• Korean journal of applied entomology
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• v.38 no.1
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• pp.47-52
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• 1999

Effects of organic matter content in soil on activity. vertical migration. and persistence of two nernaticides. carbofuran and ethoprophos. to root-knot nematode, Mrloitlog!~iei ~lcognita.w ere investigated. As the organic matter content increased. activity of the nernaticides tended to be reduced. Both nematicides exhibited control values of more than 80'k' to M. iix.o,yilit~iln 0-2 cm depth soil layer from the surface. regi~rdless of organic matter content in soil. In 2-4 cm depth soil layer. however. the control value of the neniaticides varied with the organic niatter content in soil. The control value of carbofuran in the soil layer was ranged from I0 to 30'2,. depending on the soil organic niatter content. In contrast. ethoprophos had no control value against M. i/ic.o,ytlitcr in the \oil layer, except that the nematicide had a control value of 30% when the organic matter content was 0.4%. Furthermore. ethoprophos had no effect on controlling M. i/ic.o,gtiitrr in soil layer of below 4cm. whereas control values of carbofuran were approximately from 5 to 20% in all test soils having different organic matter contents. These results indicate that carbofuran has more vertical migration effect than ethoprophos. Persistence of the two neniaticides was also decreased with increasing soil organic matter content. Half life of carbofuran was 2-3 weeks in soil containing 0.4% organic matter, whereas it was found to be I week in soils containning 0.8 ant1 1.6% of organic matter. On the other hand. activity of ethoprophos was reduced to half in 3-3 weeks and in 2-3 weeks in soil containing 0.4 and 0.8%, and 1.6%) of organic matter, respectively. However, no activity of the both nernaticides was found in soil containing 3.2% of organic matter.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.330-337
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• 2005

This study was investigated to elucidate the pesticide mobility in three different soil textures(Heongseong sandy loam; Chuncheon, loam; Taeback, silty clay loam) and four different gravel contents(0, 20, 40, 60%) of Taebaek soil using soil column. Carbofuran, which ranks the highest water solubility among 7 pesticides(carbendazim, carbofuran, chlorpyrifos, cypermethrin, dimethomorph, diniconazole and endosulfan) was defected over 87% in leachate samples within all soil types from early sampling time. Amount of 5 residual pesticides excluding carbendazim and carbofuran were ordered silty clay loam > loam > sandy loam, indicating pesticide residues are related to percentage of clay contents in soils. Comparing the amount of residual pesticides in soil column(upper, middle and lower layer), 6 pesticides apart from carbofuran were found in the range of $50{\sim}92%$ on the upper layer of silty clay loam and loam. Mobility of pesticides either in soil or leachate samples is dependant on water solubility of pesticide and clay content of soil. The results obtained from four different gravel contents of Tacback soil were similar to the results of three different soil textures. Also it was found that more the gravel contents, faster the flow velocity of leachate water. These results possibly provide an idea to select proper pesticides and to reduce soil and water contamination at alpine and sloped-land.

• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.45-50
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• 2003

This study was conducted to understand the role of oxidative enzyme cytochrome $P_{450}$ in the bioactivation of benfuracarb and to know metabolites of benfuracarb by cytochrome $P_{450}$. The bimolecular imhibition rate constant $(k_i)$ of benfuracarb on acetylcholinesterase (AChE) was as low as $1.1{\times}10^3\;M^{-1}\;min^{-1}$, suggesting that benfuracarb should be activated for its toxic action. The potency of benfuracarb on AChE in the oxidase system (cytochrome $P_{450}$ + NADPH) in vitro was 10-fold higher than that of control (cytochrome $P_{450}$). Such a similar result was also found in the oxidase + PBO system. In vivo the $I_{50}$ of benfuracarb was 22.7mg $kg^{-1}$, but pie-treatment of piperonyl butoxide (PBO) reduced the $I_{50}$ by >100mg $kg^{-1}$. This result suggests that cytochrome $P_{450}$ was involved in the activation of benfuracarb. Using microsomal oxidase system, metabolites of benfuracarb were elucidated. Fifty-eight percent of benfuracarb was converted to carbofuran, a major toxic metabolite, in the oxidase system, while only less than two percent of benfuracarb was converted to carbofuran in the oxidase + PBO system. These results also suggest that cytochrome $P_{450}$ was involved in the activation of benfuracarb. Overall results indicate that cytochrome $P_{450}$ could be involved in the bioactivation of benfuracarb to carbofuran.