• Korean journal of applied entomology
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• v.37 no.2
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• pp.207-212
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• 1998

Tea field-collected populations of the tea red spider mite (Tetranychus kazawai Kishida) from five different locations in the southern region of Korea were assessed for resistance to seven acaricides using leaf spray method. There were considerable differences in susceptibility depending on the tested acaricides and the location from which the population was collected. The populations showing high resistance ratio of more than 20 with respect to certain acaricide were as follows: the Sungjun and Cheju populations to azocyclotin, tebufenpyrad, fenpyroximate, pyridaben, propargite, and fenpropathrin; the Haenam population to propargite and fenpyroximate; the Bosung population to propargite; the Youngam population to pyridaben. Therefore, the use of other alternative acaricides against the Sungjun and Cheju populations is needed. However, careful selection of the appropriate acaricide against the Haenam, Bosung and Youngam populations of the tea red spider mite might be maintained in effective control.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.243-248
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• 1996

This study was conducted to select the acaricides selective to H. axyridis and examine the effects on phytophagous mites and natural enemies after application of selected acaricides in the apple orchard. All the acaricides tested were more toxic to T. urticae and P. ulmi than to H. axyridis, and also were more toxic to egg than to the larva and adult of H. myridis. Azocyclotin and fenpropathrin were the highest and lowest selective acaricides to H. axyridk, respectively. The density of phytophagous mites was high affected by frequency of acaricide application. Significant difference in the changes of the density of natural enemies was not be observed according to frequency of acaricide application and kinds of acaricide. Acaricide treatment showed high effect on the population densities of A. womersleyi and Oriur spp., while less effect on Chrysopa spp.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.328-333
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• 1995

Susceptibilies of tow-spotted spider mite (Tetranychus urticae Koch) collected at 6 locations were assessed to 15 acaricides. The response to acaricides were almost similar in female adults and eggs. There were considerable difference in susceptibility depending on the acaricide treated and the region from which the population was collected. The population showing resistance ratio of more than 20 with respect to certain acaricide was regarded as a resistant population to the acaricide. The resistant populations in terms of female adult were as follows: Suwon population to azocyclotin, cyhexatin, and fenbutatin-oxide; Taejon population to dicofol and fenbutatin-oxide; Chongju population to dicofoll Chinju populatin to cyhexatin, dicofol, and fenbutatin-oxide. The resistant populations in terms of egg were as follows; Suwon population to bifenthrin, clofentezine, hexythiazox, and tetradifon; Kunwi, Chongju, and Kwangju populations to bifenthrin; Taejon population to amitraz and bifenthrin; Taejon populatin to amitraz and bifenthrin; Chinju population to amitraz, bifenthrin, clofentezine, dicofol, and tetradifon. However, the female adults and eggs of all field populations were susceptible to abamectin, chlorfenson, and fenpyroximate. This tendency was also reported previously in the susceptible strain from laboratory.

• Journal of Food Hygiene and Safety
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• v.36 no.1
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• pp.17-23
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• 2021

This evaluation tested the skin irritation and sensitization of an acaricide (Wagoojabi II®, WGJB) for the control of poultry red mite, containing 20% Chamaecyparis obtusa oil and 56% Cinnamomum camphora oil. In a primary skin irritation test, rabbits were dermally treated with WGJB for 24 h. The acaricide did not induce any adverse reactions such as erythema and edema on intact skin sites, but on abraded skin sites, some rabbits showed very slight erythema and edema 24 h after topical application. So, the acaricide was classified as a practically mild-irritating material based on a 0.625 primary irritation index score. In the skin sensitization test, guinea pigs were sensitized with intradermal injection of 0.1mL WGJB for 24 h. After 1 week, The WGJB was treated on the site of injection, and challenged 2 weeks later. The WGJB did not induce any allergic reactions. Therefore, the WGJB was graded as a weak material at '0' in both sensitization score and rate. From the results of this study, it is suggested that WGJB does not cause contact irritation and sensitization.

• Korean Journal of Veterinary Research
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• v.54 no.2
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• pp.117-120
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• 2014

Chemotherapeutic treatment is still the foundation of tick control programs. This study investigated the acaricidal efficacy of cypermethrin alone and in combination with chlorpyrifos against Haemaphysalis (H.) longicornis. Unfed larval ticks were exposed to 0.1, 1.0, and 10 mg/mL cypermethrin for 60 min, after which the acaricidal efficacy was examined based on tick mortality. All compounds showed similar suppression curves, with the best control being achieved by cypermethrin and chlorpyrifos (1 : 1 ratio) at 10 mg/mL. Effective cypermethrin concentrations for tick control were two to seven times higher than the recommended doses, indicating resistance by H. longicornis.

• Journal of Applied Biological Chemistry
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• v.58 no.2
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• pp.105-108
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• 2015

This research is aimed at evaluating the potential abilities of the natural acaricide of F. suspense oil against Tyrophagus putrescentiae and Dermatophagoides spp. Based on the $LD_{50}$ values, in contact bioassay, F. suspense oil (8.19, 3.28, and $4.35{\mu}g/cm^2$) showed acaricidal effects against T. putrescentiae, D. farinae, and D. pteronyssinus, respectively. Fumigant toxicities of F. suspense oil showed similar patterns as those observed with contact toxicities. GC/MS analysis showed the major components of F. suspense oil to be ${\beta}$-pinene (45.88%), myrtenol (13.86%), (+)-${\alpha}$-pinene (13.09%), (-)-trans-pinocarveol (7.34%), sabinene (6.64%) and pinocarvone (4.13%). These findings indicate that F. suspense oil has potential as a natural acaricide.

• Analytical Science and Technology
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• v.26 no.1
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• pp.1-10
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• 2013

It was known that many beekeepers use some acaricides to protect their bees. Among the acaricides used in bees, amitraz, bromopropylate, coumaphos, and cymiazole were used commonly in Korea. In middle of 2006, Korean government set maximum residual limit (MRL) of amitraz and coumaphos as 0.2 ppm and 0.1 ppm, respectively. Because the environment of bee farm changes every year, it is needed to monitor acaricides in honey continuously. In this work, ten samples of honey collected from local markets and internet in 2011 were tested for determination of the amount of amitraz, bromopropylate, coumaphos and cymiazole by HPLC-DAD. Levels of the acaricide residues found were less than 25 ppb.

• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.179-184
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• 2000

This study was conducted to improve control system of insect pests, especially western flower thrips, Frankliniella occidentalis, and two-spotted spider mites, Tetreanychus urticae, of rose greenhouses. Density of thrips was relatively higher in yellow flowers than in pink or redflowers, while there was no difference in density of two-spotted spider mites by flower colors. In pest control by an automatic monorail sprayer, 89% labor and 18.2% chemical savings, as compared to the conventional high pressure spray method, were achieved without lowering the pest control effectiveness. By using an adhesive agent in combination with acaricide, adhesion of chemical to crops increased by 25% and control effect on two-spotted spider mites increased by 20.5% as compared acaricide spray alone.

• Korean journal of applied entomology
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• v.32 no.2
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• pp.176-183
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• 1993

These sutdies were conducted to investigate the joint toxic action of mixtures of several acaricides including amitraz, bifenthrin, propargite, fenbutatin dxide and bxide dicofol to the field-collected strian of Tetranychus urticae. The synergistic action of acaricidal mixtures was greatly varied with the kind of acaricide combinations and their mixture ratios. The combinations of amitraz with each of the tested acaricides were synergized at the given mixture ratios. The higher synergistic action in the each combination was observed at 2 : 8 ratio of amitraz and bifenthrin, 8 : 2 ratio of amitraz and fenbutatin oxide, 4 : 6 ratio of amitraz and propargite and 6 : 4 ratio of amitraz and dicofol.

• Journal of Apiculture
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• v.34 no.4
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• pp.305-313
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• 2019

Honey bees (Apis mellifera) forage in agricultural areas, and are exposed to diverse pesticide poisoning. Toxic effects on Apis mellifera of different groups of pesticides were tested in the laboratory; fungicide (Metconazole), herbicide (Glyphosate), acaricide (Amitraz), organophosphate insecticide(Fenitrothion) and neonicotinoid insecticides(Thiacloprid, Thiamethoxam, Imidacloprid, Acetamiprid, Dinotefuran and Clothianidin). Commercial formulations were serially diluted from the recommended concentration (RC) to 10-6 times to carry out feeding and contact tests. Toxicity was transformed into lethal dose (LD50) and hazard question (HQ). The acute toxicity of pesticides showed similar patterns between feeding and contact tests. But feeding tests showed greater toxic to honey bee than contact test. The organophosphate and nitro-neonicotinoid insecticides were highly toxic with HQ values ranging greater than 1. However, cyano-neonicotinoids of Thiacloprid and Acetamiprid showed low toxicity. Even at the RC, 24 hr mortalities were 18 and 30%. The acaricide (Amitraz) showed intermediate level of toxicity at RC but negligible at the concentration lower than 10-1 times. A fungicide(Metconazole) and herbicide(Glyphosate) showed minimal impacts. The results imply that the selective use of pesticides could help conservation of pollinators in agricultural production systems.