• Korean journal of applied entomology
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• v.37 no.1
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• pp.65-71
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• 1998

Survey was conducted on the kinds and densities of pests associated with stored garlic collected from farms of major garlic production areas from 1994 to 1995 in Korea. Aceria tulipae, Rhizoglyphus sp., Ditylenchus dipsaci, and Tyrophagus putrescentiae were frequently detected with high densities and Tarsonemus bilobatus and Aphelenchus avenue showed relatively low detection rates and densities. Detection rate of A. tulipue was 38% in 1994, but the rate was 65% in 1995. Number of the mite ranged from 1 to 4,500 per scale. Detection rate of Rhizoglyphus sp. was 63% in 1994, but the rate was 13% in 1995 and average number of the mite ranged from 1 to 135 per scale in 1994. Garlics damaged by Rhizoglyphus sp. showed decaying symptom. T~rophagusp utrescentiae was detected from 22 farms among 32 farms surveyed in 1994 and from 21 farms among 39 farms surveyed in 1995. However, number of the mite on garlic scale was relatively lower than the other mites and its damages on stored garlic was not determined.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.30-36
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• 1997

Except for a cosmopolitan and major pest of apples, Tetranychus urticae Koch, Tetranychus mites in Korea such as T. viennensis Zaher, T. kanzawai Kishida, and T. truncams Ehara have been considered as quarantine pests by Canada and United States. Even though these mites are not feeders on apples, they are suspected to attach accidentally on apple h i t s in autumn as females enter the diapause. The characters used to identify Tetranychus mites have been confined to the shape of aedeagus in adult male. To develope a fast and accurate alternative identification protocol applied to hibernating female mites on apples, their mitochondrial DNA (mtDNA) were examined to find out any polymorphisms to discriminate each species from the other ones. Three pairs of primers for polymerase chain reaction (PCR) were used to amplify cytochrome oxidase subunit I (CO-I) coding region in mitochondrial DNA5 of four species of Tetranycus mites. The longest amplified product was estimated its size as about 680 bp. Digestion with restriction enzymes, AluI, Ddel, and Sau3A, showed length polymorphisms, which will he useful as diagnostic markers to identify Tetranychus mites. Schematic restriction maps in amplified region were shown for each species.

• The Korean Journal of Pesticide Science
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• v.12 no.3
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• pp.249-255
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• 2008

The comparative toxicity of recommended rates of three acaricides, fluacrypyrim, cyflumetofen and spiromesifen to the predatory mite, Neoseiulus womersleyi and its prey, Tetranychus urticae was bioassayed in the laboratory. Fluacrypyrim and cyflumetofen were much less toxic to adult females of N. womersleyi than to those of T. urticae. Adult female predators treated with these two acaricides produced $88{\sim}93%$ as many eggs as did control females. Fluacrypyrim and cyflumetofen did not affect the hatch of N. womersleyi eggs or the development of surviving immature predators, and $92{\sim}96%$ of immature predators reached adulthood. Spiromesifen at its treated concentration did not significantly affect the survival and reproduction of adult female predators but caused 100% mortality in larvae of N. womersleyi. Adult female predators survived on a diet of spider mites treated with fluacrypyrim and cyflumetofen, and their fecundity was not significantly affected. Moreover, immature predators developed normally on prey treated with these two acaricides. The results indicate that fluacrypyrim and cyflumetofen are promising candidates for use in integrated mite management programs where N womersleyi is the major natural enemy.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.415-425
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• 2014

This study investigated population fluctuations in two mite species in apple orchards over 20-year period. The occurrence of two major mite pests infesting apple trees, two-spotted spider mite Tetranychus urticae and European red mite Panonychus ulmi (Acari: Tetranychidae), was investigated from 1992 to 2011 in major apple-producing districts, including four to eight cities, in the southern part of the Republic of Korea. The 20-year trend revealed that more orchards were infested by T. urticae from 1992 to 1999, but thereafter P. ulmi became dominant. The observed mean density of P. ulmi was consistent, whereas that of T. urticae fluctuated during this period. The analysis of occurrence in four time periods reveals that the density of T. urticae decreased after 2002. The monthly sampling, revealed that the density of P. ulmi was higher in April, whereas the density of T. urticae was higher from May to August. This change may be due to a change in the frequency of pesticide spraying, ground vegetation management, a decrease in nitrogen fertilization, and the overall orchard management practices. However, this projection should be examined in more detail. On the basis of the findings of this study, it can be concluded that cultural practices, including fertilization, and environmental changes, such as pesticide spray frequency and integrated pest management practices, affect species dominance and population densities of the two mite species in apple orchards.

• Weed & Turfgrass Science
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• v.6 no.2
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• pp.136-150
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• 2017

Zoysiagrass mite, Aceria zoysiae is one of the main turfgrass pests causing significant damage on zoysiagrass. In this study we investigated damage by zoysiagrass mite for the selection of zoysiagrass mite-resistance turfgrass individual in natural collected turfgrass isolates transplanted in genetic resources conservation area. In the results of investigation of 295 turfgrass isolates collected from Korea, damage level was different depending on turfgrass species and individuals. Zoysia japonica was highly damaged representing 97.6%, followed by hybrid zoysia and Z. sinica with damage percentages of 87.7% and 81.1% respectively. Additionally, 2 individuals of Z. macrostachya were also damaged by zoysiagrass mite. However several individuals were not damaged by zoysiagrass mite in green house and field. Damage by zoysiagrass mite was occurred from May and peak at after July in field. The study highlighted some important resistant turfgrass individuals which can be used in the management of zoysiagrass mite.

• The Korean Journal of Pesticide Science
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• v.14 no.2
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• pp.170-174
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• 2010

The acaricidal activity of cyenopyrafen on the tea red spider mite, Tetranychus kanzawai was evaluated in laboratory and field studies. In the laboratory, cyenopyrafen was highly effective against egg, larva, protonymph and adult female of T. kanzawai. In surviving adult females of T. kanzawai exposed to cyenopyrafen, we observed significant reduction in reproduction and no egg hatch. Effectiveness of cyenopyrafen against adult female of T. kanzawai on bean leaves was lasted for 15 days at treatments of 125 and 83.3 ppm. In a field study, cyenopyrafen exhibited excellent activity to mixed developmental stages of T. kanzawai. Based on the results, cyenopyrafen could be used for the control of T. kanzawai and treatment of this acaricide at 83.3 ppm was recommended as the field rate.

• Animal Systematics, Evolution and Diversity
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• v.17 no.2
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• pp.191-205
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• 2001

This study includes the taxonomy, description, and a key to species of mites in the Family Zerconidae(Acari, Mesostigmata) from the Korean Peninsula. Materials examined and information gathered were based on 1,020 specimens which has been collected nation-wide from April, 1994 to May, 2000. As a result of this study, the following 8 species were identified : Exhinozercon orientalis Blazak, 1975, Eurozercon pacificus Halaskova, 1979, Kaikiozercon mamillosus Halaksova, 1979, Kaikiozercon peregrinus Halaskova, 1979, Koreozercon bacatus Halaskova, 1979, Mesozercon coeranus Blaszak, 1975, Mesozercon plumatus (Aoki, 1966), Zercon szeptyckii Blaszak, 1976. Predominant species was Zercon szeptyckii which has been collected more then 600 specimens at 25 localities in the Korea Peninsula. Seven species except Mesozercon plumatus(Aoki, 1966) had been recorded from North Korea but newly recorded from the southern part of Korean Penunsula.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.151-155
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• 1999

Biological control of Tetranychus kanzawai by Phytoseiulus persimilis on the Angelica utilis was done in 'walk-in' plastic tunnels. The population of T. kanzawai nymphs and adults per 4 cm2 in damaged leaf decreased from 25 mites on July 22 after 25 predatory mites per m2 were released on July 23 to 0.4 mites on September 9 and then rose to 9.3 mites on October 16, 1997. Phytoseiulus persimilis could suppress T. kanzawai to low population level from August 13 to October 1.

• 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 Zoology
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• v.31 no.2
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• pp.147-155
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• 1988

Six species of false spider mites were collected and ciassifled in South Korea. Among them, a taxonomic description was carried out on the following four species new to Korea: 1. Aegyptobia nothus Pritchard and Baker, 2. Pentomerismus taxi (Hailer), 3. P. oregonensis McGregor, 4. Brevipalpus lewisi McGregor. And also esterase and alkaline phosphatase patterns obtained by polyacrylamide slab gel electrophoresis were compared on some spades. Esterase rymogram showed difference among species in band number and mobility.