• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.75-81
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• 2000

These studies were carried out to investigate the toxicities of 38 registered insecticides to the sweetpotato whitefly (Trialeurodes vaporariorum). 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), only pyriproxyfen showed over 90% of ovicidal effect. The insecticides that showed over 90% of larvicidal activity oil 3rd nymphal instars were abamectin, acetamiprid, chlorpyrifos-methyl, imidacloprid, pyripoxyfen, and acetamiprid+ethofenprox. Insecticides with 100% adulticidal activity were abamectin, acephate, acetamiprid, benfurcarb, bifenthrin, furathiocarb, endosulfan, fenitrothion, imidacloprid, phenthoate, pymetrozine, acetamiprid + ethofenprox, ethofenprox + diazinon, furathiocarb + difluberlzuron, and triazamate+${\alpha}$-cypermethrin. Abamectin, acetamiprid, imidacloprid, pyriproxyfen, and acetamiprid + ethofenpox showed both residual effect and systemic activity. In tile control efficacy test on B. tabaci, 90% control values were obtained at 11th day after treatment of the insecticides including abamectin, acetamiprid, imidacloprid, pyripoxyfen and acetamiprid + ethofenprox. These results indicate that abamectin, acetamiprid, imidacloprid, pyriproxyfen and acetamiprid + ethofenprox can be used for tile control of B. tabaci in field.

• Korean Journal of Environmental Agriculture
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• v.24 no.4
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• pp.350-357
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• 2005

This study was conducted to investigate the downward mobility of pesticides using soil columns and to compare the experimental results with values predicted from Convective mobility test model. Nine pesticides such as metolcarb, molinate, fanobucarb, isazofos, diazinon, fenitrothion, dimepiperate, parathion and chlorpyrifos-methyl were used for leaching test in soil column for four soils; Jungdong (upland soil), Gangseo (paddy soil), Yesan (forest soil), and Sineom(upland, volcanic ash-derived soil) series. The peak concentrations leached from 10 cm-columns of three soils except Sineom series ranged 6.5 to 12.6 mg/L for metolcarb, 2.6 to 5.0 mg/L for molinate, 4.5 to 7.8 mg/L for fenobucarb, 0.39 to 1.36 mg/L for dimepiperate, 1.1 to 4.6 mg/L for isazofos, 0.01 to 0.14 mg/L for diazinon, lower than 0.01 to 0.70 mg/L for fenitrothion and lower than 0.01 to 0.44 mg/L for parathion. But chlorpyrifos-methyl was not leached from any soil columns. Elution volumes to reach the peak of metolcarb, molinate, fenobucarb, isazofos, diazinon, and dimepiperate in the leachate ranged 1.1 to 2.1 pore volume (PV), 1.6 to 3.3 PV, 1.6 to 3.3 PV, 2.1 to 4.4 PV, 6 to 15 PV, and 8 to 21 PV, respectively. On the same water flux conditions, convection times estimated by Convective mobility test model were coincided with results from soil column test in most of the soil-pesticide combinations applied. Based on convection times estimated by the model at standard conditions (water flux 1 cm/day), metolcarb was classified as most mobile, molinate, fenobucarb and isazofos as mobile or most mobile, dimepiperate as moderately mobile or mobile, diazinon as mobile, fenitrothion and parathion as slightly mobile or mobile and chlorpyrifos-methyl as immobile or slightly mobile.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.329-334
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• 2011

Insecticidal activity of 31 registered insecticides was tested against Metcalfa pruinosa adults. All experiments were conducted at the recommended concentration (ppm) of each insecticide. Among them, 16 insecticides from organophosphates (dichlorvos, fenitrothion, fenthion, methidathion, phenthoate), carbamates (methomyl), pyrethroids (${\alpha}$-cypemethrin, deltamethrin, fenpropathrin, ${\gamma}$-cyhalothrin), neonicotinoids (acetamiprid, clothianidin, dinotefuran, imidacloprid, thiamethoxam), and other (endosulfan) showed 100% mortality by spraying on the body of M. pruinosa adults. Dichlorvos, fenitrothion, fenthion, methidathion, phenthoate and endosulfan showed 100% mortality by plant-dipping method. The residual effect was showed 100% mortality in four insecticides (fenitrothion, fenthion, methidathion, phenthoate) at one day after treatment, and three insecticides (fenitrothion, methidathion, phenthoate) were showed the mortality of 90% at three days after treatment.

• The Korean Journal of Pesticide Science
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• v.11 no.3
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• pp.179-185
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• 2007

Esterase isozymes were investigated from digestive juice of M. saltuarius adults after pesticide treatment. Twelve esterase isozymes were separated on 12% native-PAGE gel and stained with three different substrates(${\alpha}$-naphthyl acetate, ${\beta}$-naphthyl acetate, and ${\alpha}$-naphthyl butyrate). Interestingly, the isozyme of Est1(${\alpha}$-naphthyl acetate) was strongly inhibited by the carbofuran and methomyl. The Est1 activity was completely inhibited by the chlorpyrifos and partially inhibited by methidation about 70 %. In addition, eserine suppressed esterase isozyme activities of Est1 about 70% and isozyme activities of Est2, Est3, and Est4 were weakly inhibited. ${\alpha}$-pinene did not suppressed esterase isozyme activities but activities of esterases were very weakly inhibited in camphor and bornyl acetate.

• The Korean Journal of Pesticide Science
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• v.11 no.3
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• pp.194-200
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• 2007

Insecticidal activity of 33 registered insecticides was tested against last nymphal instars and adults of ussur brown katydid (Paratlanticus ussuriensis). All experiments were tested at the recommended concentration of each insecticides by producer. Acephate, chlorpyrifos, diazinon, EPN and fenitrothion which were organophates, and a mixture combined with chlorpyrifos+${\alpha}$-cypemethrin showed 100% mortality of P. ussuriensis. But fipronil showed only 100% mortality in leaf-dipping method. Carbamates insecticidal groups, benfuracarb and furathiocarb were showed over 80% and phenthoate was $60{\sim}80%$ in mortality of P. ussuriensis. Among the mixture, etofenprox+diazinon and esfenvalerate+fenitrothion were showed 60-80% against last nymphal instars of P. ussuriensis. Otherwise, acephate, chlorpyrifos, diazinon, EPN and fenitrothion were showed 100% mortality of P. ussuriensis within only 24 hours after treatment, but there was no effective after then in residual tests with leaves.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.57-61
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• 2001

Tank mixing application of pesticides has been used to reduce labor and to control wide spectrum of pests, but it may cause significant pesticide poisoning on human and animals due to carelessness. The toxic response of pesticides for the tank mixtures and mixtures was investigated to determine acute toxicity and enzymatic change using experimental animals. Acute oral toxicity and acute dermal toxicity were tested by RDA test guideline. The $LD_{50}$ was calculated by probit analysis method and cholinesterase was measured with automatic analyzer. The toxicities were generally higher than estimated toxicities in tank mixing and mixture. Serum cholinesterase activity was inhibited more than expected at the dose levels of 1/5, 1/10 and 1/20 of $LD_{50}$. Therefore, the results of this study showed that acute toxicity caused by the pesticide mixtures should be considered before the tank mixing method is applied.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.54-63
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• 2015

Streptomyces spp. isolated from turfgrass rhizosphere and tested for their response to large-patch control fungicides. The tested fungicides were actually used in golf course or turfgrass cultivation to prevent large-patch disease. Tolerance to 3 triazole group of the strains was the highest to the PR fungicide, and following the SR fungicide, whereas the isolated strains were no tolerance to HR fungicide. Tolerances to three kind of Strobilurin group were similar for the all of the tested Streptomyces spp.. Growth and sporulation of the all strain was normal in CB and AP fungicide treatments. However no spore formulated in double concentration. Strains, tolerance to acetanilide fungicides, appeared that KT fungicide tolerance was higher than MK fungicide. The selected strains showed strong tolerance against AT fungicide but have no tolerance to ATR fungicides. In conclusion, the bacterial strains showed tolerance against 1 carbamate, 1 organophosphate and 1 cyanopyrrole group, while have no tolerance against two mixture formulations (1 Quinone + Strobilurin and 1 Imidazole + Triazole).

• 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.

• The Korean Journal of Pesticide Science
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• v.11 no.4
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• pp.246-253
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• 2007

The reproduction toxicity of several pesticides on two Korean water flea was investigated to develop a new standard species used for ecological risk assessment of pesticide. Moina macrocopa and Daphnia sp. were exposed to 4 different types of pesticides over 10 and 21 days, respectively. No-ohserved effect concentration (NOEC) for synthetic pyrethroid, fenpropathrin on Moina macrocopa and Daphnia sp. were 0.17 and $0.06\;{\mu}g\;L^{-1}$, respectively. Diazinon, carbofuran and myclobutanil were in the order of their reproduction toxicity to cladocerans tested. There were large differences between Moina macrocopa and Daphnia sp. in their susceptibility to fenpropathrin, diazinon and carbofuran except myclobutanil. Daphnia sp. is more sensitive than M. macrocopa to pesticides tested. Therefore Daphnia sp. may be a good surrogate species to assess the reproduction effect of pesticides on aquatic invertebrates. M. macrocopa also be a good surrogate species because it is one of the most abundant cladocera in agricultural environment, especially rice paddy in Korea. In addition to it's ecological importance of wide spread distribution, it has also economical importance to make possible to shorten period for reproduction test using M. macrocopa due to it's short life cycle.

• The Korean Journal of Pesticide Science
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• v.7 no.4
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• pp.288-295
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• 2003

To determine the mechanism of the resistance to organophosphorus insecticide, chlorpyrifos, in diamondback-moth (Plutella xylostella L.), activities of esterases, glutathione-S-transferase (GST) and AChE insensitivity which were known for causing factor of resistance were measured. Also, the relationship between AChE insensitivity and the resistant ratio was investigated to inquiry the cross-resistance. The resistant ratio of chlorpyrifos-resistant strain (CRS) of diamondback-moth at the 6th generation was developed 160 fold compared to susceptible strain (SS) one. Activity of GST that are extracted from CRS was 1.7-fold higher than that from SS. However, activity of total esterases from CRS was similar to that from SS. In AChE insensitivity test, CRS was 11.8-fold less sensitive than that from SS. CRS was ranged from 17.6 to 33.6-fold less sensitive than SS to other insecticides having same target site with chlorpyrifos such as dichlorvos, dimethylvinphos and carbofuran. Insensitivity of AChE to phenthoate-oxon, however, was 1.7-fold. Resistance of CRS was 82-fold, 47-fold and 42-fold higher than SS to dichlorvos, dimethylvinphos and carbofuran, respectively, but 2.3-fold to phenthoate and then we could identify that the resistance development of insecticide might have a lot of difference among the chemicals with the same target site. The relationship between the AChE insensitivity and the resistant ratio was significantly correlated$(r=0.9951^{**},\;p^{(0.01)}$. This result indicates that AChE insensitivity was associated with insecticide resistance. Overall, these results suggest that insensitivity of AChE was an important factors to chlorpyrifos resistance in diamondback-moth, and the slightly increased activity of GST may also have contributed to that.