• The Korean Journal of Pesticide Science
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• v.19 no.2
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• pp.101-105
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• 2015

Efficacy of novel nematicide, imicyafos GR was evaluated against two species of the root-knot nematodes in pot and greenhouse conditions. When tested in pots, the population of Meloidogyne incognita and M. hapla was reduced sixty days after treatment, with mortality rate of 91.5% and 90.6%, respectively. Suppression effect of imicyafos GR on root galling in tomato was tested. The number of root galls caused by M. incognita and M. hapla was reduced 60 days after nematode inoculation, with the efficacy of 94.2% and 95.1%, respectively. Under greenhouse conditions planted with watermelon, melon, cucumber, and tomato, the efficacy of imicyafos GR on M. incognita persisted up to 60 days after treatment, showing 90% of control efficacy. Moreover, the number of root galling was more reduced than fosthiazate treatment, with the potential as a control agent.

• Analytical Science and Technology
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• v.27 no.5
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• pp.234-242
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• 2014

Imicyafos which is a nematicide for controlling root-knot nematodes has been registered in the Republic of Korea in 2012, and the maximum residue limits of imicyafos are set to watermelon and korean melon as each 0.05 mg/kg. Extremely reliable and sensitive analytical method is required for ensuring food safety on imicyafos residues in agricultural commodities. Imicyafos residues in samples were extracted with acetone, partitioned with hexane and dichloromethane, and then purified with florisil. The purified samples were analyzed by HPLC-UVD and confirmed with LC-MS. Linear range was between 0.1~5 mg/kg with the correlation coefficient ($r^2$) 0.99997. Average recoveries of imicyafos ranged from 77.0 to 115.4% at the spiked levels of 0.02 and 0.05 mg/kg with the relative standard deviations of 2.2~9.6%. Limit of detection and quantification were 0.005 and 0.02 mg/kg, respectively. An inter-laboratory study was conducted to validate the determination method in depth, and the results were satisfactory. All of the validation results revealed that the developed analytical method in this study is relevant for imicyafos determination in agricultural commodities and will be used as an official analytical method.

• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.293-299
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• 2016

Effect of nematicidal compounds on hatchability of sugar beet cyst nematode, Heterodera schachtii and its infective juveniles was investigated. The sugar beet cyst nematode was isolated from Chinese cabbage field in Samcheok in Korea. Acute toxicity of nematicidal compounds against infective juveniles was also tested to find the $LC_{50}$ by exposing juveniles to given dilutions of each compound. Hatchability and mortality of infective juveniles of H. schachtii were influenced by nematicidal compounds (Fluopyram 40% SC, imicyafos 30% SC, fosthiazate 30% SC, abamectine 1.68% SC, terthiophene, and Eclipta prostrata extract). Fluopyram and imicyafos yielded the lowest rates of hatching. Total hatched infective juveniles were significantly different among nematicidal compounds. Positive correlation in percentage reduction of hatching was observed in fluopyram. Furthermore, the highest mortality was also observed in the treatments of fluopyram and imicyafos ($LC_{50}$ of 0.0543 and 0.0178 ppm respectively). The study, therefore, demonstrated available alternative nematicidal compounds which could be used in the control of H. schachtii.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.361-369
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• 2020

This study aimed to investigate the differences in the effects of nematicidal materials (Burkholderia rinojensis, fluazaindolizine, fluopyram, fosthiazate, hydrogen peroxide, and imicyafos) on eggs and larvae of the sugar beet cyst nematode, Heterodera schachtii and clover cyst nematode, H. trifolii, which have recently become problematic in highland Chinese cabbage cultivation areas in Korea. Comparison of the hatching rates according to the test materials showed differences between treatments. In the treatment with fluopyram, fosthiazate, and imicyafos, a very high hatching inhibitory effect of 99% was observed in both nematodes, and there was no difference in the efficacy of treatments between nematode species except for that with hydrogen peroxide. Regarding the nematocidal activity of treatments against hatched larvae, only the fluazaindolizine treatment, despite showing a high hatching inhibitory effect, showed a low nematicidal effect of less than 30% against both nematodes, whereas a mortality rate of more than 90% was observed in the other treatments. There was no difference between nematode species in the reactions of the 2nd instar juveniles to all nematicidal test materials after 24 and 48 h of treatment. Although there are limitations to the laboratory experiment, the reaction to the nematicidal materials of the two cyst nematodes that damage the same host was similar, and simultaneous control is suggested in the areas where the two nematodes occur together.