• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.155-161
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• 2013

The residue patterns of clothianidin and thiacloprid, insecticides registered in the ginseng, were investigated to predict pre-harvest residues limits (PHRL). Pesticides were treated under Korea GAP (Good Agricultural Practices) with the recommended dose (single dose) and twice of recommended dose (double dose). Samples were collected 11 times over 42 days (each 0, 2, 5, 8, 12, 16, 20, 24, 28, 33, 42 days after treatment). Residues of clothinidin and thiacloprid were analyzed by UPLC/TQD. Biological half-life of clothinidin in single dose and double dose were 14.6 days and 10.2 days and that of thiacloprid were also 9.7 days and 11.2 days, respectively. The PHRL of ginseng on 10 days before harvest was 0.3 mg/kg in clothianidin and 0.18 mg/kg in thiacloprid.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.42-48
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• 2017

This study was conducted to compare the effect of bagging technique on the presence of pesticide residues in various parts of grape fruit (whole fruit, pulp and peel). The tested pesticides were diluted at 2,000 times and sprayed three times onto the crops at an interval of seven days and then they were collected at 0, 1, 3, 5 and 7 days after final application. Later, bagging/non-bagging samples were pre-treated with fruit, pulp and peel samples, respectively. Thiacloprid and lufenuron were not detected in any of the bagging samples. The thiacloprid residues of non-bagging samples in whole, peel and pulp samples were 0.47-1.09, 0.18-0.33 and 1.24-1.67 mg/kg, respectively. The lufenuron residues of non-bagging samples in whole fruit, peel and pulp samples were 0.16-0.62, < LOD-0.08 and 0.85-1.48 mg/kg, respectively. The biological half-lives of thiacloprid and lufenuron in whole fruit, peel and pulp of non-bagging samples were 5.7, 15.1 and 7.8 days and 4.0, 9.4 and 2.6 days, respectively. While the unbagged samples showed a sequential decrease in pesticide residues, this study concludes that bagging would be an effective method to protect the presence of thiacloprid and lufenuron residues in grape fruits.

• The Korean Journal of Pesticide Science
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• v.13 no.2
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• pp.98-104
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• 2009

This study was carried out to investigate the residue patterns of two neonicotinoid insecticides, dinotefuran and thiacloprid, commonly used for cucumber, were subjected to indicate a residual characteristic under greenhouse conditions. The pesticides were sprayed onto the crop at recommended and double doses 7 days before harvest and then sampling was done 0, 2, 3, 5, and 7 days after spraying. The amounts of their residues in the crop were analyzed with an HPLC. Their detection limits were 0.01 mg/kg for dinotefuran and 0.005 mg/kg for thiacloprid. Mean recoveries of dinotefuran and thiacloprid were from 85.78 to 89.52 and from 85.71 to 95.31%, respectively. Half-lives of dinotefuran and thiacloprid were 2.8 and 1.8 days at the recommended dose and 2.8 and 1.5 days at the doubled dose, respectively. The ratios of the EDI to ADI by intake the crop harvested 7 days after spraying were less than 0.1% of their ADIs.

• The Korean Journal of Pesticide Science
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• v.12 no.3
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• pp.262-269
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• 2008

This study was performed to investigate the toxicity of 39 registered insecticides to the susceptibility, systemic effect, and residual effect and control effect against Pine sawyer beetle, Monochamus saltuarius. Eleven kinds of chemicals such as fenitrothion, fenthion, phenthoate, phosphamidon, dinotefuran, actamiprid, clothianidin, thiacloprid, thiamethoxam, esfenvalerate+fenitrothion, and fipronil were showed 100% insecticidal activity both in body spray and twig dipping bioassay. Among these chemicals, fenitrothion and fenthion were showed 100% insecticidal activity when sprayed at 4000 times diluted solutions, and phenthoate, thiacloprid, thiamethoxam and fipronil were showed 100% insecticidal activity when sprayed at 2000 times diluted solution. Root systemic effect was showed 100% mortality in phosphamidon, clothianidin, thiamethoxam, and 77.7% in thiacloprid. In residual effect, fenitrothion and thiamethoxam were showed 80% mortality fifteen days after treatment (DAT), and fenthion, phosphamidon, clothianidin were showed 80% mortality ten DAT, fenitrothion, thiamethoxam, fipronil showed 100% mortality in seven DAT, thiacloprid was showed 100% mortality in three DAT. Fenthion and phenthoate were showed 100% mortality one DAT. In the control effect, 6 kinds of chemicals were showed 100% mortality one DAT and all chemicals showed 100% mortality three DAT.

• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.159-164
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• 2009

This study was carried out to elucidate changes in concentration of pesticide residues in Chinese matrimony vine and jujube during drying. Test pesticides, triadimefon and triforine for chinese matrimony vine and methoxyfenozide and thiacloprid for jujube, which are commonly used for the crops in Korea, were treated to the crops by spraying and dipping. The pesticide residues in both fresh and dried Chinese matrimony vine and jujube were analyzed by using a GLC-ECD and an HPLC-DAD. Processing factors of the pesticides in Chinese matrimony vine and jujube by drying ranged from 1.41 to 2.28 and from 1.50 to 4.20, respectively. And reduction factors of the pesticides in the crops ranged from 0.29 to 0.47 and from 0.68 to 0.98, respectively. These results indicate that concentrations of the pesticides in the test crops increased after drying, while amounts of pesticides in them were diminished by drying.

• Korean Journal of Environmental Agriculture
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• v.39 no.2
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• pp.122-129
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• 2020

BACKGROUND: Dissipation patterns of insecticides (acequinocyl, clothianidin, diflubenzuron, thiacloprid, and thiamethoxam) on strawberry grown in plastic-covered greenhouse were evaluated at 7 intervals including the preharvest interval after application. This study was performed to determine the residue concentrations, half-lives and dissipation rates in strawberry for the harvest periods. METHODS AND RESULTS: Acequinocyl, clothianidin, diflubenzuron, thiacloprid, and thiamethoxam were applied in accordance with critical good agricultural practices for strawberry. Strawberry samples were collected at 0, 1, 2, 3, 5, 7 and 10 days after application. Quantitaion was performed by HPLC/DAD and HPLC-MSMS system with C₁₈ column. The limit of quantitation (LOQ) values varied between were 0.00025~0.05 mg/kg on strawberry. The recoveries of acequinocyl, clothianidin, diflubenzuron, thiacloprid and thiamethoxam at two concentrations ranged from 70.9~104.9% on strawberry. The half-lives of pesticide dissipation on strawberry for two fields ranged from 1.3~8.2 days. The dissipation rates were evaluated according to the statistics method with a 95% confidence. CONCLUSION: The residue levels of insecticides (acequinocyl, clothianidin, diflubenzuron, thiacloprid, and thiamethoxam) on strawberry at 0-day after application were below the specified values by Korean MRL. To estimate dissipation rate constant of pesticides on crop for harvest periods, it is important to set the pre-harvest residue limit for human health and consumer protection in Korea.

• Journal of Korean Society of Forest Science
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• v.106 no.4
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• pp.509-517
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• 2017

This study was conducted to assess effect of thiacloprid fogging on non-target insect communities in Korean white pine forests. In addition, we assessed effect of thiacloprid fogging on mortality of Monochamus saltuarius as a vector of pine wood nematodes, and Apis mellifera as a non-target species. We compared abundance, species richness, and compostion of insects, and mortality of two insects among four treatment groups (control and thiacloprid-fogged groups with 3 different doses) located in the Kangwon National University Forest. For sampling of insects, 6 pitfall and 2 multi-funnel traps and 3 waterproof cloth sheets were placed in each study plot. In addition, M. saltuarius and A. mellifera were put into each meshed cage which installed at 7 m and 15 m heights in center of each study plot. Thiacloprid was fogged only once (middle May) in each plot using a fogging machine. Overall, thiacloprid fogging was appeared to be low toxicity to the abundance, species richness, and compostion of insects and mortality of A. mellifera, while it seems effectively impact on the mortality of M. saltuarius. However, thiacloprid fogging seems more influenced by microclimates in forests because the mortality of M. saltuarius in mesh cages was different according to heights and spatial locations. To control the population density and dispersal of M. saltuarius using by fogging techniques, therefore, it may be necessary to minimize the uncertainty about the effectiveness of thiacloprid fogging by improving the fogging techniques.

• The Korean Journal of Pesticide Science
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• v.14 no.2
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• pp.110-115
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• 2010

The aim of this study is to investigate the exposure assessment of Korean consumers to five neonicotinoid pesticides in fruit vegetables cultivated in Korea, using a probabilistic approach. We used five neonicotionid pesticides residues(acetamiprid, clothianidin, imidacloprid, thiacloprid, thiamethoxam) data in fruit vegetables reported by Rural Development Administration for the 2009 monitoring programme. Total exposure of five neonicotinoid pesticides for Korean consumer ranged from 0.087 to 0.236 ${\mu}g$/kg/day at the $95^{th}$ percentile. The $95^{th}$ percentile values of total exposure of five neonicotinoid pesticides by probabilistic approach were lower than those by deterministic approach, although mean values of total exposure by probabilistic approach were similar with those of total exposure by deterministic approach. Total exposure to acetamiprid residue may be mainly due to the exposure to acetamiprid through the consumption of strawberry. Also, acetamiprid residues in strawberry were considered as much more contributory factor to total exposure of acetamiprid than consumption data of strawberry. This contributory properties of acetamiprid were similar with those of all other neonicotinoid pesticides, excluding thiacloprid.

• 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.

• The Korean Journal of Pesticide Science
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• v.20 no.2
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• pp.133-137
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• 2016

In Korea, six mealybug species have been reported on pears. This study investigated the occurrence of mealybugs in 19 pear orchards from 2013 to 2014. Two species, Crisicoccus matsumotoi Siraiwa (Hemiptera: Pseudococcidae) and Pseudococcus comstocki Kuwana were mainly found. The dominant species was C. matsumotoi identified on 73% of infested fruit. Toxicities of 14 registered insecticides (Buprofezin+Acetamiprid EC, Buprofezin+Amitraz EC, Buprofezin+Clothianidin SC, Buprofezin+Dinotefuran WP, Buprofezin+Etofenprox WG, Buprofezin+Thiacloprid SC, Buprofezin+Thiamethoxam SC, Benfuracarb WG, Acetamiprid WP, Clothianidin SC, Dinotefuran WG, Thiacloprid SC, Thiamethoxam WG, Sulfoxaflor SC) commonly used to control P. comstocki were evaluated to C. matsumotoi nymphs and adults at the recommended concentration. As a results, all insecticides exhibited strong insecticidal activity with 100% mortality of both nymphs and adults. These results indicate that the 14 insecticides can be used in control for C. matsumotoi in field.