• Korean journal of applied entomology
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• v.39 no.1
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• pp.53-58
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• 2000

The effect of NeemAzal-T/S was tested by leaf disk method on fecundity, egg mortality, and preference of twospotted spider mite, Tetranychus urticae and its predator mite, Amblyseius womersleyi in the laboratory. Mortalities of T. urticae and A. womersleyi adults were 97.7% and 20.0%, in 100ppm treatment at 72 h after application, respectively. The mean number of eggs laid per T. urticae female adult were 0.0 and 18.5, and those of A. womersleyi were 1.6 and 2.9 at 100 ppm and 0 ppm concentrations, respectively. Hatchability of T. urticae eggs treated with 50 and 100 ppm were 52.8%, and 2.5%, respectively, and those of A. womersleyi eggs were 100% and 91.3%, respectively. Choice and no-choice tests revealed that T. urticae female preferred to alight and oviposit on untreated bean leaf disk with 13.8 to 18.2 eggs per female. In contrast, A. womersleyi female preferred on treated or untreated bean leaf equally. There was no significant differences in the number of consumption of T. urticae eggs by A. womersleyi on treated and untreated bean leaves, except 200 ppm. These results indicate that NeemAzal-TIS is highly toxic to T. urticae, and is less toxic to A. womersleyi. It may be concluded with these results that NeemAzal-T/S could be incorporated into integrated T. urticae management system.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.145-152
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• 2006

Predation of Neoseiulus fallacis was observed for biological control of Panonychus citri that is one of the major insect pests on citrus. The daily predation of development stages of P. citri by an adult female of N. fallacis were 20.1 eggs, 26.1 larvae, 18.2 protonymphs, and 7.4 deutonymphs at 25$^{\circ}C$, The daily predation of P. citri eggs by N, fallacis was observed under different temperatures. The predation was increased as the temperature rise. At this time, ratio of eggs production of l! fallacis after predation of P. citri eggs (number of eggs N. fallacis/number of eggs P. citri consumed by N. fallacis) was 0.09. The daily predation of P. citri eggs by N, fallacis was 21.1, 17.3, and 16.7 on the different arenas (diameter: 20, 40, and 60 mm), respectively. The predation was decreased as the arena of the leaf increase. The functional response of M fallacis to P. citri showed Holling's Type II response: the consumption of prey by N. fallacis increased as the density of prey increase but increasing rate was gradually reduced. As the result, it seemed that N. fallacis can be use for biological control of P. citri.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.197-201
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• 2003

These studies were carried out to investigate the amounts and preferences of Oligota kashmirica benefica to 3 species of phytophagous mites and cannibalism. The number of mites consumed by an adult beetle tended to increase as prey density and temperature go up. In the constant temperature of 25$^{\circ}C$, average number of consumed adult mites by an adult of O. kashmirica benefica to Panonychus citri, Tetranychus urticae and T. kanzawai were 21.9, 13.5, and 14.1 for a day, respectively. The number of mites consumed by larva of O, kashmirica benefica tended to increase as the larva grow up. First, 2nd and 3rd larva of the beetle consumed 2.8, 11.2 and 25.4 adult of citrus red mite (P. citri) for a day, respectively. Total number of mites consumed during larval stage (5 days, 25$^{\circ}C$) to P. citri, T. urticae and T. kanzawai were 77.7, 61.3 and 73.0, respectively. The larva and adult beetle did not prefer specific species in the P. citri, T. urticae and T. kanzawai, and when there was no diet, few incidents of cannibalism between different developmental stage were observed.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.173-177
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• 2006

Biological control of Tetranychus urticae by Phytoseiulus persimilis was observed in eggp1ant greenhouse fur spring and autumn season culture. Tetranychus urticae was controlled to low density of less than 1 mite from June 24 after p. persimilis were released 3 times at rate of 10 per plant on June 1, 11, and 18, 2004 in spring season experiment. The population of Tetranychus urticae was also less than 1 mite per eggp1ant leaf from September 1 to October 22 after three times releases of 10 P. persimilis in autumn season experiment. In Phytoseiulus persimilis released plot, the percentage of leaves with T. urticae adults and nymphs were 8.6$\sim$13.3% and 5% or less in spring and autumn season experiment. The density of T urticae was from 1 to 2 on leaves with T urticae adults and nymphs.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.126-131
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• 1996

These experiments were conducted in the laboratory conditions to determine the prey consumption of a predaciousphytoseiid mite, Amblyseius womersleyi Schicha, and its ability to regulate the population of tea redspider mite, Tetranychus kanzawai Kishida. The functional response curve of the adult A. womersleyi to thedensity of eggs, larvae, and nymphs of T. kanzawai indicated Holling's Type 11: the consumption of prey bythe adult A. womersleyi increased with the prey density but the consumption rate decreased. The critical initialratio to suppress the prey population by the predator seemed to be 32:l @rey:predator) at 25"C, and 16:l at20$^{\circ}$C on kidney bean plant. The predator could not regulate any initial ratio of the prey population at 15$^{\circ}$C.^{\circ}$C.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.115-123
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• 2005

Historical changes of population abundances of European red mite (ERM), Panonychus ulmi (Koch), and two-spotted spider mite (TSSM), Tetranychus urticae (Koch) (Acari: Tetranychidae), were described in selected apple orchards in the National Horticultural Research Institute (NHRI, Suwon, Korea), based on research reports of the NHRI from 1958 to 1998. ERM was an abundant species up to 1970, and TSSM became a dominant species after 1980. The change occurred around mid 1970. Three hypotheses were made to explain the change: TSSM competitively replaces ERM, ground cover weeds are a major influencing factor on movement of TSSM (TSSM movement into trees is accelerated by destroying weeds), and ERM and TSSM populations are regulated by natural enemy complexes when the orchard system is not disrupted. And long-term results of the interaction between two species were projected according to the combination of different orchard management strategies: pesticide sprays (non-selective toxic pesticide spray : heavy pesticide pressure (HPP), and selective soft pesticide spray = low pesticide pressure (LPP)) and weed control methods (grass planting, and clean culture system with herbicides). In the HPP and grass planting system, ERMs are abundant because ERM can avoid competition with TSSM as movement of TSSM to trees are restricted, and natural enemy complexes are destroyed by toxic pesticides. In the HPP and clean culture system, TSSMs are abundant because TSSM moves to trees from early season and competitively replaces ERM. In the LPP and grass planting system, ERMs are abundant because movement of TSSM to trees is reduced, but they do not build up a high population density since their densities are regulated by natural enemy complexes. In the LPP and clean culture system, TSSM moves to trees and competes with ERM, but the competition pressure is reduced because population densities of mites are regulated in a lower level by natural enemy complexes. So, ERM can occurs in late season. Thus, two species can coexist temporarily with more ERM in early season and more TSSM in late season. TSSM abundant phenomenon presented in this study can be partially explained as a result of long-term interaction between ERM and TSSM under the HPP and clean culture system.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.54-57
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• 2003

Mites were isolated from soil samples of forty localities in Korea during the period of 1995-2003. Of them, three species of Aceosejidae are newly recorded in Korea: Platyseius mollicomus (Berlese, 1916) Sejus nepalensis Evans & Pyatt, 1960 Zerconopsis decemremiger Evans & Pyatt, 1960.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.291-294
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• 2013

Typhlodromips geumgangensis n. sp. is described in Korea. Typhlodromips paraki, newly recorded species from this country, is redescribed based on Korean specimens, and key to the species of the genus Typhlodromips is provided.

• Korean journal of applied entomology
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• v.35 no.4
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• pp.280-286
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• 1996

The present work describes four new species of oribatid mites, which were collected from Sangumburi in Chejudo, Korea. They were Brasilobates sangumburiensis sp. nov., Xenillus multisetosus sp. nov., Nippobodes tamlaensis sp. nov., and Nippobodes chejuensis sp. nov.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.6 no.6
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• pp.63-73
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• 1985

최근에 과수농가의 농민과 원예 및 능금조합의 지도기사들을 대상으로 과수해충 방제실태에 대한 설문조사를 한 결과, 사과원에서는 응애류가 심식충류나 진딧물보다 방제가 어려운 해충으로 지적되고 있다. 또한 필자가 전국 6개 지역의 15개 일반 농가의 사과원을 2년간 년 3회 이상 관찰한 결과에서도 심식충류의 피해를 받고 있는 농가는 거의 없었으며, 응애류는 그 발생정도에 차이는 있으나 대부분의 사과원에서 상존하고 있는 현상이었다. 이와 같이 응애류가 사과원에서 주요해충으로 등장하게 된 이유는 첫째, 시비$\cdot$농약살포 등 관리상태의 향상으로 사과나무 잎의 생리적 조건이 변화되어 응애류의 생식력을 자극시켰기 때문이라는 ''생식자극설''(生殖刺戟設)과 둘째, 1940년대 후반 이후 농약 사용의 급증으로 인하여 응애류의 발생을 억제하던 포식성 응애를 비롯한 천적류가 감소 또는 멸종되었기 때문에 응애류가 격발(激發)하게 되었다는 ''포식자억제설''(捕食者抑制設) 등이 있다.