• Korean Journal of Environmental Agriculture
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• v.16 no.2
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• pp.149-155
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• 1997

This study was carried out to investigate the effects of phenobarbital sodium(PB) and 3-methylcholanthrene(3-MC) on carbofuran cytotoxicity and to develop antitoxic agents based on the effectivness. Experimental groups for carbofuran cytotoxicity were divided into five groups ; medium alone and four treatments of carbofuran (1, 25, 50 and $100{\mu}M)$, and those for compensation effects were divided into six groups ; medium alone, $IC_{50}$ carbofuran and four combinations of carbofuran and PB or 3-MC($IC_{50}$ carbofuran plus 1, 25, 50, $100{\mu}M$ of PB and 3-MC, respectively). After incubation for 48 hrs under the same conditions, MTT(Tetrazolium MTT), NR(Neutral red) and SRB(Sulforhodamine B protein) assay were performed. Fifty percentage inhibition of MTT, NR, and SRB against carbofuran in rat fibroblast cell were 60.7, 82.5 and $87.0{\mu}M$, respectively. At the combination treatments of $IC_{50}$ of carbofuran and $100{\mu}M$ of PB, the significant compensation effects were observed from the results of MTT and NR but not from that of SRB absorbance. And at the combination treatments of $IC_{50}$ of carbofuran and 3-MC, the relatively significant compensation effects were found at $50{\mu}M$ 3-MC from the results of MTT and at $100{\mu}M$ 3-MC from that of NR and SRB absorbances, respectively. From the results of light microscopy, combination treatments of $carbofuran(IC_{50})$ and PB or 3-MC showed good regeneration in carbofuran toxicity of rat fibroblast cells. These results suggest that PB or 3-MC can compensate the cytotoxity of carbofuran insecticide in rat NIH3T3 fibroblast cells.

• Korean Journal of Veterinary Research
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• v.33 no.3
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• pp.455-460
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• 1993

In the present study, the effects of 4 agricultural chemicals commonly used in this conuntry were experimentally assessed on Lymnaea viridis the intermediate host of Fasciola hepatica, which in non-target organism of these chemicals. The major habitat of the snail is rice paddies in Korea and many agricultural chemicals are used for weed, fungi or insect control in rice paddies and there is a general concern that certain levels of these chemicals could reach the aquatic ecosystem and possible alter the snail life. Agricultural chemicals used in this study included two herbicides, an insecticide and a fungicide. The tenth generation of laboratory reared snails were selected and exposed to the varying concentrations(0-100 ppm) of these chemicals. As concentrations and time of exposure increase, the per cent mortality increases(p<0.01). $LC_{50}$(lethal concentration for 50% mortality) values of these chemicals on snail after 96-hour exposure were variable; iprobenfos showed the highest acute toxicity(12.6 ppm), while carbofuran showed the lowest acute toxicity(74.5ppm). Sublethal concentrations of chemicals after 96-hour exposure were also variable ; bentazone showed the highest chronic toxicity(0.81ppm), while carbofuran showed the lowest chronic toxicity(5.04 ppm).

• Korean Journal of Environmental Agriculture
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• v.8 no.2
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• pp.103-118
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• 1989

In order to investigate the uptake of the systemic insecticide, carbofuran, 2,3-dihydro-2,2-dimethyl-7-benzofuranyl-N-methyl(arbamate) residues, fresh and aged, by rice plants, they were grown for 42 days in soils containing freshly treated (T-1), 3-month-aged (T-2), and 6-month-aged residues (T-3). The amounts of $^{14}CO_2$ evolved from $^{14}C-carbofuran$ during the 3-and 6-month aging in soil (temp. $22{\pm}1^{\circ}C$ ; moisture, 50% of the maximum water-holding capacity) were 8.9 and 26.7% of the original radioactivity applied, respectively. Mineralization of $^{14}C-carbofuran$ in soil to $^{14}CO_2$ during 42 days of rice growing was 4.4% (T-1), 11.0% (T-2), and 15.7 (T-3). The methanol extract of the 3-and 6-month-aged soils revealed that 3-keto carbofuran phenol (2,3-dihydro-2,2-dimethyl-3-oxo-7-benzofuranol) was the major metabolite, where as 3-hydroxy carbofuran (2,3-dihydro-2,2-dimethyl-3-hydroxy-7-benzofuranyl-N-methylcarbamate) turned out to be the major metabolite in the shoots by the enzymatic cleavage of the possible conjugate present in the methanol extract. Volatilization of $^{14}C-carbofuran$ in soil during 3-and 6-month-aging, and 42 days of rice growing was 0.026, 0.05, and 0.012-0.018% of the applied radioactivity, respectively. The $^{14}C-radioactivity$ which was absorbed from the soils by rice plants during 42 days of the growing period and persisted in rice plant tissues was 26.8, 21.4, and 10.3% in T-1, T-2, and T-3, respectively. The non-extractable bound residues were 8.3, 37.9, and 54.6% of the originally applied carbofuran in T-1. T-2, and T-3, respectively. The small translocation of $^{14}C-radioactivity$ in T-3 upwards suggests that major metabolite 3-keto carbofuran phenol is conjugated in roots and the low recovery in T-1 indicates the loss of carbofuran from the shoots.

• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.35-39
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• 2000

In order to develop the indicators of environmental impact of pesticide, its actual usage in paddy rice was surveyed, and usage trends of individual pesticides were evaluated. The tendency of pesticide use indicated insecticide 43%, herbicide 29%, fungicide 27% and top ranking item in insecticide, herbicide and fungicide was carbofuran, molinate + pyrazosulfuran-ethyl, IBP. The usage statistics of formulation types showed GR>DP>WP>EC>FG>SP. Pesticide usage(a.i.) per hectare was 7.13kg and total usage for paddy rice was estimated at 8,387 M/T. In the result of comparison of fact-usage with pesticide consumption reported in 1998, the fitness was 94.7% for fungicide, 84.3% for insecticide, 77.8% for herbicide. The result of monitoring pesticide residue of unpolished-rice sampled from farm house of survey indicated 0.14 ppm(BPMC), 0.16 ppm(Isoprocarb), 0.17 ppm(Isoprothiolane). In case of rice straw, the residue level was 0.27 ppm(Isoprothiolane), 0.28 ppm(IBP), 0.39 ppm(Carbofuran). The residue levels of pesticides were below MRLs.

• The KIPS Transactions:PartB
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• v.9B no.5
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• pp.663-672
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• 2002

In this paper, Using an automatic tracking system, behavior of an aquatic insect, Chironomus sp. (Chironomidae), was observed in semi-natural conditions in response to sub-lethal treament of a carbamate insecticide, carbofuran. The fourth instar larvae were placed in an observation cage $(6cm\times{7cm}\times{2.5cm)}$ at temperature of $18^\circ{C}$ and the light condition of 10 time (light) : 14 time (dark). The tracking system was devised to detect the instant, partial movement of the insect body. Individual movement was traced after the treatment of carbofuran (0.1ppm) for four days 2days : before treatment, 2 days : after treatment). Along with the other irregular behaviors, "ventilation activity", appearing as a shape of "compressed zig-zag", was more frequently observed after the treatment of the insecticide. The activity of the test individuals was also generally depressed after the chemical treatment. In order to detect behavioral changes of the treated specimens, wavelet analysis was implemented to characterize different movement patterns. The extracted parameters based on Discrete Wavelet Transforms (DWT) were subsequently provided to artificial neural networks to be trained to represent different patterns of the movement tracks before and after treatments of the insecticide. This combined model of wavelets and artificial neural networks was able to point out the occurrence of characteristic movement patterns, and could be an alternative tool for automatically detecting presences of toxic chemicals for water quality monitoring. quality monitoring.

• 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.

• Korean journal of applied entomology
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• v.18 no.4 s.41
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• pp.149-152
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• 1979

The relative toxicity of some of the insecticides which have been used for the control of paddy rice insect pests in Korea was evaluated in the laboratory with the brown planthopper (BPH) Nilaparvata lugens, and a predaceous paddy spider Pirata subpiraticus. In order of the relative toxicity (LD5O value to spider/LD50 value to BPH) were PAP (0.4), MPP(0.1), MEP(1.8), diazinon(2.8), carbofuran(7.5), NAC(11.3), BPMC(17.5), Pyridaphenthion(35.9) and MIPC(65.7). MIPC and Pyridaphenthion were considered as having the desirable selective toxicity for the spider and the BPH.

• Journal of Ecology and Environment
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• v.32 no.1
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• pp.19-25
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• 2009

An arthropod community in a rice ecosystem was surveyed to determine the impact of two insecticides frequently used in Korean rice ecosystems: carbofuran 3GR, which targets the rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae) in the early season and fenobucarb EC, which targets the brown planthopper, Nilaparvata lugens ($St{\aa}l$) (Hemiptera: Delphacidae) in the mid- and late seasons, respectively. Overall, the application of the insecticides reduced density of total arthropods by 48.4% compared to the untreated field, but their impact on each functional group were different. Carbofuran GR treatment on 1 June reduced the L. oryzophilus population significantly until mid-season. The population of filterfeeding chironomids was also reduced by 50%, whereas the spider population was less disturbed. Fenobucarb EC treatment on 16 August significantly reduced N. lugens and detrivorous entomobryid populations until the late season. Both web-building and wandering spiders were also significantly disturbed by fenobucarb EC although the impact differed according to their behavioral differences. While the population of web-building spiders significantly decreased over time, that of wandering spiders recovered from the disturbance a few weeks later.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.351-356
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• 2017

For determining the insecticidal effect of Carbofuran on the Brown planthopper, Nilaparvata lugens, sucking toxicity by drenching application, sucking and contact toxicity by leaf dipping application, and contact toxicity by topical application were examined. Drenching caused two types of mortality patterns. One was logarithmic curve at a relatively high concentration (8~30 ppm) with over 40% mortality in 24 h, and the other was an S-shaped curve at low concentrations (1~4 ppm) with over 60% mortality on the fifth day after Carbofuran treatment. Leaf dipping application caused a rapid increase in mortality in a day, and this effect decreased steadily with time. Topical application showed steep increase in mortality in a day, and hardly increased thereafter. The best mortality evaluation time for the drenching application was the second day (42 h), and that for the leaf dipping and topical applications was the first or second day after Carbofuran application. When the insecticide has systemic effects, drench application provides the best efficacy and its insecticidal effects persist for a longer time than any other application method.

• Journal of Korean Society of Forest Science
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• v.85 no.3
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• pp.439-442
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• 1996

In this study, we tried to figure out the ecology of Masakimyia pustulae Yukawa et Sunose which attacts evergreen euonymus and results in scenic damage caused by early falling of leaves and may increase the susceptibility for anthrocnose. In addition, we tried to develope a method for the control of the insect to prevent spreading of the damage by use of insecticide. The results obtained from the study were as follows : 1. Masakimyia pustulae emerged from late April to late May at Chuncheon area. Average length of the adult insects was $1.88{\pm}0.43mm$, and the life span of them reached about 11 hours. The sex ratio of the insect was 56 : 44(female : male), and they ovipositied $90{\pm}28$ eggs. The shape of eggs was oval with average length $0.32{\pm}0.013mm$. The length of larvae averaged $1.64{\pm}0.25mm$ and started pupation from mid-March, which took about 40~50 days, although there was variance due to temperature variation in each spring. 2. The 3% powder of carbofuran treatment by burying $200g/m^3$ of the insecticide around the damaged tree during mid-March with additional burying about a week after pupation showed good result for the control of the insect, which resulted in more than 96.2% removal of the insects.