• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.194-200
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• 2011

Diamondback moth (DBM, Plutella xylostella L.) is known as the most destructive pest of cruciferous crops worldwide. As most insecticides targeted to mainly larval stage, new insecticides which have hatching-inhibitory or ovicidal activity could be more efficient to control DBM. Therefore, we developed an easy and efficient method for screening ovicidal activity of DBM eggs using aluminum foil. The aluminum foil ($4{\times}12$ cm) coated with filtered juice of chinese cabbage leave (hereinafter called oviposition foil) exposed to 300 newly-emerged adults for 24 hours inside the rearing container. The oviposition foils were replaced every 4 days consecutively after mating, but it was better to discarded over then. Oviposition foil were divided into 6 to 12 pieces depending on egg mass volume. After dipping into test solutions for 10 seconds using faucet, oviposition foil pieces were placed into common petri dish, and then investigated hatchability. The effect of methanol solvent (50%) for 10 seconds dipping on the toxicity against DBM eggs was negligible. In addition, whether covering the petri dish or not should be dependent on nature of active compounds tested. With applying the new bioassay method, methanol extracts from 50 plants were tested the ovicidal activity to DBM eggs. Among them, four plant extracts; Angelica tenuissima root, Lycium chinense root, Cnidium officinale root and Polygala tenuifolia root, showed high ovicidal activity of over 90% control efficacy, against DBM eggs.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.249-255
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• 2003

These studies were carried out to investigate fumigant, contact toxicity and repellency effects of 34 terpenes against acaricide susceptible the two-spotted spider mite, Tetranychus urticae. In addition, the efficacy was also tested against two acaricide-resistant strains. Two terpenes, isosafrole and safrole showed fumigant toxicity of 98.4%, at 10${\mu}\ell$/1 (air) concentration. LD$\_$50/ values of these two terpenes were 2.6${\mu}\ell$/1 and 4.3${\mu}\ell$l/1, respectively. Most terpenes showed low or no contact toxicity, except isosafrole showing 60.2% mortality against eggs. Hexanoic acid and limonene showed repellency effects of 79.1%, 87.8%, respectively, to the susceptible strain at concentration of 1,000 ppm in the lab conditions. Hexanoic acid (1,000 ppm) showed repellency effected of 77.8% and 83.3% to fenpropathrin and pyridaben resistant strains, respectively. However, limonene showed no repellency to the two resistant strains.

• Applied Biological Chemistry
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• v.40 no.3
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• pp.249-253
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• 1997

The acaricidal and ovicidal activity against red spider mite (Tetranychus urticae) was examined for a series of S-aryl arenethiosulfonates and compared with sulfonate acaricide, ovex and senile. Substituted diphenyl disulfides were obtained from substituted thiophenols, chloronitrobenzene and aniline derivatives. The S-aryl arenesulfonothioates were synthesised from the oxidation of disulfides. Three kind of para substituted compounds were found to have good ovicidal effect but acaricidal activity against adult mite was negligible in all S-aryl arenethiosulfonates.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.471-478
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• 2011

The ginseng stem fungus gnat, Phytosciara procera, overwintered in old stems and roots of ginseng as a larvae from late September to early May in next year. In the late Spring they become pupa then emerged. Therefore, the first control period has to be set between late May and early June. It is a same period of elimination of ginseng flower stalks. Two or three times pest control might be needed per month for controlling adult of P. procera. Otherwise, the overwintered form as larva in old stem by removal of old stems of ginseng, the population of first generation of P. procera adults could be reduced. However, it seemed that the removal of old stems was not necessarily correlated with the population of P. procera adults in the next generation. Three kinds of environmental-friendly control agents that were mainly contained sophora extract, showed the highly insecticidal activities against larva of P. procera. Among them, one agent containing sophora extract and paraffin oil showed an ovicidal action as well as oviposition repellency.