• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.257-263
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• 2002

This study was carried out not only to investigate the toxicities of 12 registered insecticides on different developmental stages, but also to determine the sublethal effects on longevity and reproduction of newly emerged adult female and development of the next generation in the rice skipper, Parnara guttata. Fenitrothion, fenthion, cartap hydrochloride, ethofenprox highly suppressed egg-hatch. All insecticides treated showed high larvicidal activity on the 1st to 2nd instar larva. The insecticides showed higher larvicidal activities on the 5th instar larva were fenitrothion, fenthion, ethofenprox, fipronil, methoxyfenozide, tebufenozide and Bt. var. kurstaki. The sublethal doses of fenthion, tebufenozide, cartap hydrochloride, methoxyfenozide, ethofenprox, imidacloprid and fipronil shortened the longevities of newly emerged adult female from the treated larva ($3{\sim}4$ instar). BPMC, imidacloprid, ethofenprox, fipronil and methoxyfenozide delayed the preoviposition periods of adult females and decreased the number of eggs laid when they were treated at the larval stages of the previous generation. Ethofenprox caused severe sublethal effects on P. guttata offspring, completely blocking the production. All insecticides except fenitrothion affected the egg viability, and all eggs from the adult females emerged from the survivors treated larvae with imidacloprid or fipronil fail to hatch. IGRs, methoxyfenozide and tebufenozide showed an adverse effect on the development of next generation larva.

• 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.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.12a
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• pp.121-123
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• 2005

• Korean journal of applied entomology
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• v.63 no.1
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• pp.13-23
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• 2024

Vespa velutina nigrithorax du Buysson, 1905 is the invaded species in Korea since 2003. Since its importance as the honey bee pest, beekeepers use insecticides to kill the adult and immature hornets. However, its legality and effectiveness has not been confirmed. This study investigated the susceptibility of insecticides commonly used to control hornets by beekeepers in Korea. Eight insecticides were tested on adult worker and larvae by topical or oral treatment. Adults showed more than 70% mortalities from Clothianidin, Dinotefuran, and Carbosulfan treatment within 30 minutes. Bifenthrin and Cartap hydrochloride showed relatively low toxicity. The median lethal dose (LD₅₀) for Clothianidin, Dinotefuran, and Carbosulfan was 0.29, 0.65, and 2.21 ㎍/bee, respectively. In larval feeding test where 5^th instar larvae were fed 3 times every 24 hours, the mortality began after second treatments. After 3rd treatments (72 h), all insecticides showed mortality more than 70%. The LD₅₀ values of Clothianidin, Dinotefuran, and Carbosulfan to V. velutina were approximately 10 to 100 times higher than those to honey bee, Apis mellifera. This study provides the basic information of those chemical toxicities to Vespa hornet and honey bees.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.51-58
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• 2000

These studies were carried out to investigate the toxicities of 43 registered insecticides to the sweetpotato whitefly(Bemisia tabaci, B. biotype). Insecticide activities were evaluated by testing systemic action and residual effect in the laboratory, and control efficacy in the greenhouse. All experiments were tested at the recommended concentration(ppm) of each insecticides. Insect growth regulators (IGRs), pyriproxyfen and teflubenzuron showed >95% ovicidal effect. The insecticides that showed >95% larvicidal activity on 3rd nymphal instars were abamectin, acetamiprid, imidacloprid, pyriproxyfen, and acetamiprid+ ethofenprox. Insecticides with >95% adulticidal activity were abamectin, acetamiprid, diazinon, endosulfan, fenitrothion, imidacloprid, methidathion, pirimiphos-methyl, pymetrozine, spinosad, acetamiprid+ ethofenprox, cartap kydrochloride+buprofezin, and fenpropathrin+fenitrothion. Abamectin, acetamiprid, imidacloprid, pyriproxyfen, and acetamiprid+ethofenprox showed both residual effect and systemic activity. In the control efficacy test on B. tabaci, 90% control values were obtained at 1st day after treatment of the insecticides including abamectin, acetamiprid, imidacloprid, pyriproxyfen and acetamiprid+ethofenprox but in pyriproxyfen, 90% control value was reached at 7th day after treatment. These results indicate that abamectin, acetamiprid, imidacloprid, pyriproxyfen and acetamiprid+ethofenprox can be used in control for B. tabaci in field.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.382-390
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• 2008

This study was performed to evaluate the acute toxicity and residual toxicity of the 69 kinds of agrochemicals (41 insecticides, 18 fungicides, and 10 acaricides) against honeybee, Apis mellifera and bumblebee, Bombus terrestris. According to the IOBC standard, the toxicity showed below 30% was classified as non-toxic. Among 41 insecticides, five insecticides (acetamiprid, chlorfenapyr, thiacloprid, milbemectin, and buprofezin+amitraz) against the honeybee; eight insecticides (methomyl, thiodicarb, acetamiprid, chlorfenapyr, thiacloprid, abamectin, spino sad, buprofezin+amitraz) against the bumblebee did not show any toxic effect. Therefore, it thought to being safe. Other 18 fungicides and 10 acaricides were safe against the honeybee and bumblebee. In residual toxicity against the honeybee, eight insecticides (dichlorvos, methomyl, imidachlorprid, emamectin benzoate, spinosad, cartap hydrochloride, chlorfenapyr, and endosulfan) among 41 insecticides tested were safe at three days after treatment; however, sixteen insecticides (dimethoate, fenitrothion, fenthion, methidathion, phenthoate, pyraclofos, fenpropathrin, clothianidin, dinotefuran, thiamethoxam, abamectin, acetamiprid+ethofenprox, acetamiprid+indoxacarb, bifenthrin+imidacloprid, ethofenprox+phenthoate, imidacloprid+methiocarb) still remain high toxicity at eleven days after treatment. Against the bumblebee, residual toxicity showed as safe in seven insecticides (dimethoate, methidation, a-cypermethion, ethofenprox, indoxcarb, chlorpyrifos+a-cypennethrin, esfenvalerate+fenitrochion) at three days after treatment; however, eight insecticides (fenitrothion, pyraclofos, clothianidin, fipronil, acetamiprid+ethofenprox, chlorpyrifos+bifenthrin, ethofenprox+phenthoate, imidacloprid+methiocarb) still showed high toxicity at seven days after treatment. From above results, it will be useful information to select insecticides being safe and effective against the honeybee and bumblebee.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.323-329
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• 1993

These studies were conducted to evaluate the five comparative test methods for detecting chemical resistance and to investigate resistant level of field populations of diamondback moth (Plutella xylostella L.). Leaf disc method was practically rocomrnendable because of its rapidity and low CV(l1.4%). Topical application method was a precise replicabiliLy(CV=8.00/0) but it was time consuming and difficult in mampulation. The other 3 methods showed higher CV ranging from 14.9% to 21.4%. Based on $LC_{50}$ values by topical application method, field populations of diamondback moth collected from 4 different regions, Kwangju, Kimhae, Jeju, and Inje to prothiofos showed from 3.3 to 61.1 times higher resistance than the susceptible strain, whereas to cypermethrin, Lhey were from 7.5 to 141.7 times higher than the susceptible. To cartap hydrochloride, they showed from 10.5- to 33.3-fold resistant levels as high as the susceptible. Finally, based on $LC_{50}$ values to Bacillus thuringiensis by leaf disc technique, the resistant levels of the field populations were from 1.9 Lo 8.1 times as compared to the susceptible.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.427-434
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• 2017

The susceptibility of Dermanyssus gallinae adults, collected from poultry farms in 5 regions, to 11 acaricides was investigated. When bifenthrin and formic acid with pyridaben were diluted 100 times, bifenthrin showed 100% acaricidal activity; however, formic acid with pyridaben showed less than 20% acaricidal activity for poultry farms in 3 regions (Gyeongju, Chilgok, and Geumsan) except Yeoncheon and Anseong. The carbamate compound, carbaryl showed 100% acaricidal activity in most of the regions, except Gyeongju. A phosphorus compound, dichlorvos showed 100% activity in most of the regions, yet 66.7% acaricidal activity in Yeoncheon. The susceptibility of D. gallinae from poultry farms in Yeoncheon and Anseong to most acaricides was high; however, in the other farms, the susceptibility of D. gallinae varied depending on the acaricide. Clothianidin, thiamethoxam, fenitrothion, and formic acid with pyridaben showed differences in acaricidal activity among regions. Therefore, farmers should concentrate during the selection of these acaricides. However, carbaryl, cartap hydrochloride, dichlorvos, and bifenthrin showed high activity against D. gallinae collected from poultry farms in five regions. Therefore, these acaricides could be used in most of these regions. To control D. gallinae effectively, the alternation of acaricides is necessary, and indiscriminate pesticide use should be avoided. Therefore, this study can serve as a basis for controlling D. gallinae.

• Analytical Science and Technology
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• v.9 no.1
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• pp.91-97
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• 1996

The extent of binding($K_B$) between chemical compound and humic acid was measured as an indicator of decrease in toxicity. From the experimental $K_B$ and estimated $K_B$ calculated from $K_{ow}$, no reduction of toxicity among test chemicals in aquatic systems were predicted except P,P'-DDT. The effect of humic acid on aquatic organisms is not expected to be significant for the compounds with $K_B{\leq}10^5$ or $K_{ow}{\leq}10^6$.

• Korean Journal of Medicinal Crop Science
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• v.8 no.1
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• pp.74-78
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• 2000

This study was carried out to select the effective insecticides for control of Ostrinia furnacalis(Guenee) in Yonchon, northern part of Kyunggi province, where is main producing region of adlay in Korea. The Asian corn borer in adlay field had three generations a year. The first stage of adult activity was higher from late May to middle June, the second from late July to early August and the third late September. Based on difference in control value, the relative ranks of some insecticides were lambda cyhalothrin EC > cartap hydrochloride GR > carbaryl EC. In control value by different application timing of Lambda cyhalothrin EC, yields were significantly different, that is, twice applications on second generation showed the control value of $90.6%{\sim}93.5%$. Unhulled grain yield on Lambda cyhalothrin EC treated plot on second generation was higher than that in untreatred plot by 82%.