• Korean journal of applied entomology
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• v.63 no.1
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• pp.75-76
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• 2024

The ovicidal effect of plant extract mixture (5%cinnamon extract + 10% citronella oil + 30% citrus oil + 10% derris extract + 20% neem extract + 25% penetrating surfactant) against several major insect pests was tested using the spraying method. In the case of stink bugs, eggs tended to die during hatching. When treated with a plant extract mixture (500-times solution), mortality for Halyomorpha halys, Riptortus clavatus, Eurydema dominulus, Trialeurodes vaprarorium, Bemisia tabaci, Spodoptera exigua, and Agrotis ipsilon reached as high as 100%. Therefore, it is believed that industrialization will be feasible in the future.

• 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.3 no.2
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• pp.74-80
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• 1999

These studies were carried out to investigate the effects of nonsteroidal ecdysone agonist, tebufenozide on embryonic and postembryonic development of sycamore lace bug, Corythucha ciliata. Tebufenozide exhibited ovicidal activity($LC_{50}=4.0$ ppm). Susceptibility of each instar nymphs to tebufenozide was nearly same($LC_{50}=2.3{\sim}6.0$ ppm). The tebufenozide treatment in the final instar affected the emergence, longevity and fecundity of surving adults significantly. Tebufenozide applied at high concentration (10 ppm) to younger adults delayed prioviposition period, and decreased adult longevity, the number of eggs laid per female and hatchability. The treatment also inhibited the ovarian development of the female adults.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.399-405
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• 2020

The susceptibility and control efficacy evaluated for 10 kinds of commercialized acaricides, to obtain basic data for the chemical control strategy of Two-spotted spider mite (Tetranychus urticae) in Hooker chives. The susceptibility evaluation of T. urticae female adults, Abamectin EC, Pyflubumide SC, Cyenopyrafen SC, and Acequinocyl SC showed 100% mortality, and Pyflubumide SC, Acequinocyl SC, and Etoxazole SC showed zero hatching rate, i.e. 100% mortality of eggs. As a result of evaluating the field test for Abamectin EC, Pyflubumide SC, Cyenopyrafen SC, Cyflumetofen SC, and Acequinocyl SC, which had excellent mortality in the laboratory conditions, all treatment plots showed more than 90.3% control efficiency on after 7 days.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.480-485
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• 1992

Laboratory studies were done to evaluate the effects of diflubenzuron on embryonic and postembryonic development of Riptortus clavatus Thunberg. Diflubenzuron prevented egg hatch; younger eggs(O-12 h old) were 2 times as susceptible as older(48-60 h old) eggs, but embryos of both younger and older eggs developed normally. Susceptibility of nymphs to diflubenzuron decreased with each successive molt. Compared with the first instar, relative tolerance to diflubenzuron was 1.5 times for the second instar, 18.2 times for the third instar, 39. 4 times for the fourth ins tar and 42.4 times for the fifth instar. Even as low concentrations, diflubenzuron prevented significant numbers of third instar nymphs from developing to fourth and fifth instar nymphs or adults. Weight, longevity and fecundity of adults surviving treatment in the final (fifth) instar were also adversely affected.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.707-717
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• 2018

The acaricidal activity of extracts of Gleditsia japonica var. koraiensis, Camellia sinensis, Cinnamomum cassia, Lantana camara and their mixtures against the tea red spider mite, Tetranychus kanzawai was evaluated. Treatments with mixtures 3 and 1 were effective against the adult females of T. kanzawai and yielded 82.0% and 77.3% adulticidal activities at 7 days after treatment, respectively. Treatment with mixture 2 revealed 68.0% adulticidal activity. Generally, the acaricidal activity of the single treatment of each plant extract was lower than the mixtures. The adult females of T. kanzawai treated with mixtures 3 and 1 produced only 24.0~29.6% as many eggs as control females did. The residue of the plant extracts tested had low adulticidal activity (16.7~31.3% at 7 days after treatment). All the plant extracts tested exhibited no remarkable toxic effect to the eggs of T. kanzawai. Treatments of mixtures 3 and 1 were effective against nymphs of T. kanzawai and led to emergence rates of 16.7 and 22.0%, respectively. These results suggest that mixtures 3 and 1 might be used for the control of T. kanzawai in tea fields.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.975-985
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• 2015

The susceptibility of the twospotted spider mite, Tetranychus urticae and the predatory mite, Phytoseiulus persimilis to extracts of Melia azedarach, Piper nigrum, Syringa velutina and their mixtures was evaluated in laboratory bioassays. Treatments of mixture 1 and 2 were effective against adult females of T. urticae and yielded 73.3 and 70.7% adulticidal activity at 7 days after treatment, respectively. Treatment of mixture 3 revealed 62.7% adulticidal activity. However, M. azedarach, P. nigrum and S. velutina had lower adulticidal activity than the other treatments. Adult females of T. urticae treated with mixture 1 and 2 produced only 11.1-16.7% as many eggs as control females did. All the plant extracts tested were ineffective to against the eggs of T. urticae. Plant extracts tested had little effect on the survival of P. persimilis adult females. Moreover, reproduction of P. persimilis adult females and eclosion of eggs deposited by treated predators were not seriously affected. Treatment of plant extracts tested showed no toxic effect on P. persimilis eggs and produced 100% hatchability. These results suggest that mixture 1 and 2 might be used for the control of T. urticae, and expected to be promising candidates for use in integrated mite management program with P. persimilis.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.232-237
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• 1996

Toxicity of 5 acaricides, 4 insecticides. and 6 fungicides to the twospotted spider mite, Tetranychus urticae Koch, and its predator Amblyseius womersleyi Schicha was assessed in a laboratory using a leaf disk bioassay. Dicofol was equally very toxic to aduly females of T. urticae and A. womersleyi, and caused 46% and 40% mortality of eggs of those two species, respectively. Adult females of A. womersleyi dipped in Abamectin solution showed low mortality(16.6%), while all T. urticae females died within 24 hours after dipping. Three ovicidal acaricides (Tetradifon, Clofentezine, and Hexythiazox) showed no mortality of predator eggs, but more than 90% mortality of T. urticae eggs. Four insecticides (Teflubenzuron, Triflumuron, Diflubenzuron, and Imidacloprid) and three fungicides (Propineb, Fenarimol, and Polyoxin-B captan) were non toxic to the A. womersleyi adult females. The other fungicides (Chlorothalonil, Nuarimol.Mancozeb, and Folpet) were a little toxic to adult females of the predator, showing$\leq$23.3% mortality, It may be suggested from these results that 4 insecticides, 4 acaricides, and 6 fungicides described could be incorporated into the integrated pest management system with A. womersleyi in apple orchard.

• The Korean Journal of Pesticide Science
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• v.3 no.3
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• pp.60-67
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• 1999

Insecticidal activities of imidacloprid to sucking type insect pests, brown planthopper (BPH, Nilaparvata lugens) and peen peach aphid (GPA Myzus persicae), to chewing type insect pests, tobacco cut worm (TCW; Spodoptera litura) and beet armyworm (BAW, Spodoptera exigua) and to spiders, Pirata subpiraticus, Pachygnata clercki and Ummeliata insecticeps, as natural enemies were investigated by several bioassay methods. $LD_{50}$ of the chemical by topical treatment to BPH was 0.015 ${\mu}g/g$(48 hrs), while $LC_{50}s$ by leaf dipping and root zone treatment were 18.1 and 21.5 ppm, respectively. There was no difference in insecticidal activities between leaf dipping and root zone treatment. Imidacloprid also showed ovicidal effect of root zone treatment and its $LC_{50}$ was 6.8ppm $LD_{50}$ (48 hrs after treatment) of imidacloprid to GPA was $0.4{\mu}g/g$ in case of topical application and $LC_{50}s$ by leaf dipping and root zone treatment were 1.9 ppm and 13.7 ppm respectively. Leaf dipping was more effective than root zone treatment in GPA At topical application $LD_{50}$ (48 hrs after treatment) of imidacloprid to chewing type insect pests, TCW and BAW, were greater than 1,492 and $312{\mu}g/g$ and $LC_{50}s$ by leaf dipping method were 4,803 and Heater than 5,000ppm respectively. This means that imidacloprid has much less effect on chewing type insect pests, TCW and BAW. $LD_{50}$(48 hrs after treatment) of imidacloprid to wandering spiders, Pirata subpiraticus, Pachygnata clercki at topical application were greater dan $2941{\mu}g/g$ and greater than $2,976{\mu}g/g$ respectively and that to webbing spider, Ummeliata insecticeps, was 357 ${\mu}g/g$. Imidacloprid showed very low toxicity to the spiders and its selective toxicity ratios between spiders and BPH were greater than 19,600, greater than 19,800 and 23,800, respectively.

• 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.