• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.40-47
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• 2000

The comparative toxicity of ten acaricides, seven insecticides and five fungicides to the two-spotted spider mite, Tetranychus urticae and its predators, Amblyseius womersleyi and A. eharai was evaluated by a leaf spray bioassay. Five of the acaricides tested, bifenazate, etoxazole, acequinocyl, flufenoxuron and chlorfenapyr were much less toxic to adult females of A. womersleyi and A. eharai than to T. urticae adult females. A. womersleyi adult females treated with five acaricides produced $52{\sim}93%$ as many eggs as untreated adult females. And A. eharai adult females treated with five acaricides laid $54{\sim}73%$ as many eggs as untreated adult females. The remaining acaricides showed high toxicity to adult females of A. womersleyi and A. eharai. All the insecticides tested were less toxic to T. urticae adult females than to adult females of A. womersleyi and A. eharai. However, tebufenozide and diflubenzuron did not significantly affect the survival and reproduction of adult females of A. womersleyi and A. eharai. All the fungicides tested showed low mortality (${\leq}24%$) to adult females of predatory mites. However, benomyl had significant effect on the reproduction of adult females of A. womersleyi and A. eharai. Four acaricides (bifenazate, acequinocyl, flufelloxuron and chlorfenapyr) were much less toxic to eggs of A. womersleyi and A. eharai than to T. urticae eggs. However, etoxazole caused relatively low hatchability ($58{\sim}62%$) of eggs of A. womersleyi and A. eharai. All the insecticides and fungicides tested did not significantly affect the hatch of eggs of predatory mites. It may be suggested from these results that four acaricides, two insecticides and four fungicides described could be Incorporated into the integrated mite management system with A. womersleyi and A. eharai in pear orchard.

• Korean journal of applied entomology
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• v.36 no.3
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• pp.224-230
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• 1997

A~nblyseius eharui and A. firllat~dic~w~esr e most abundant among Korean phytoseiid mites. The most favored plant\ chosen for habitats by Korean phytoseiid mites were Castanetr CI-enatcia nd P ~ L ~ ~.sIerLruIlaSt( i var. spontruleo. A. ehcirui, A. finltrr~(lic.us.a nd A. rc~omrrvleyia re most common and found on majority of plants observed.

• Korean journal of applied entomology
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• v.36 no.2
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• pp.129-133
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• 1997

Amblyseius (Amblyseius) barkeri, A. (A.) womersleyi, A.(A.) eharai, and Phytoseius (Pennaseius) hongkongensis are recorded in Korea, are redescribed based on specimens from island. The subgenus Pennaseius is recorded for the first time in this country.

• The Korean Journal of Soil Zoology
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• v.9 no.1_2
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• pp.24-28
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• 2004

Predaceous phytoseiid mites can be important components in integrated mite management program including bio-logical control of spider mites. While conducting population study of prey-predator system in pear orchards, 6 predaceous phytoseiids were found. Amblyseius womersleyi, A. eharai, A. kokufuensi and A. finlandicus were mostly found from tree canopy. While A. rademacheri was restricted in ground vegetation, A. makuwa was equally distributed in ground vegetation and tree trunk. Some ecological information for each species was reviewed. Strate-gies for their potential utility in pest management program and future study area were discussed.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.257-262
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• 2003

Spider mites and their predacious mites were surveyed in an apple orchard where pesticides have not been applied for a long time, to understand the undisrupted predacious mite complex and their role in the controling spider mites. Spider mites occurring in the orchard were different to those in conventional orchards. A few Tetranychus urticae and Panonychus ulmi were observed, while T. kanzawai was abundant during growing season. Four species of phytoseiids, Amblyseius eharai, A. kokufuensis, A. womersleyi and Typhlodromus vulgaris, and one stigmaeid species of Agistemus terminalis were observed from leaf samples in the orchard. Among them, T. vulgaris occurred from early cool season with low T. kanzawai densities through to mid-and late-season. A. womersleyi was observed only during mid-season when T. kanzawai densities were high with hot weather. Amblyseius eharai and A. kokufuensis occured only in early season, but A. terminalis density increased from mid-season and lasted to late-season. The predacious mite complex regulated the density of T. kanzawai approximately under 8 mites per leaf. Tentatively concluding, T. vulgaris is an adaptable predator at lower prey density under cool weather condition, and A. womersleyi is effective predator at higher prey density under hot weather condition. Further, the biological control strategies of spider mites in Korean orchards were discussed based on the predacious mite complex.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.249-255
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• 1995

These experiments were conducted to investigate the life history and the seasonal fluctuation of population density of tea red spider mite, Tetranychus kanzawai Kishida and to observe its natural enemies in the southern area. Under field-cage conditions, tea red spider mite occurred 11~12 generations. The average periods from egg to adult emergence were 8.7~13.1 days in summer and 12.6~24.9 days in spring and autumn. The average longevities of adults were 15.5~21.9 days in summer and 25.1~31.6 days in spring and autumn. The average number of eggs laid per female were 45.1 in summer and 52.6 in spring and autumn. Tea red spider mite population showed two peaks during April-June, and appeared third or forth peak during October-November. The density of all the stages was the lowest in July through August. Tea red spider mites stayed at lower parts of tea plants in March but they moved to upper parts in April though June, and they again moved to lower parts after autumn. Tea red spider mite overwintered as all stages. Adults were the dominant overwintering stage during this stage. The surveyed natural enemies of the tea red spider mite were 7 species including Amblyseius longispinosus (Evans), A. eharai Amitei et Swirski, Anystis baccarun (L), Agistemus fleschneri Summers, Orius sauteri Poppius, Oligota yasumatsui Kistner and Scolothrips sp.