• Korean Journal of Veterinary Service
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• v.35 no.3
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• pp.183-189
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• 2012

Tsutsugamushi disease or scrub typhus cause by Orientia tsutsugamushi is an endemic disease in Korea. Chigger mites and field rodents play roles in transmission of the disease by the vector and host of the agent. The purpose of this study is to investigate the density of the chigger mites and field rodents due to environmental factors such as temperature, relative humidity, soil thickness and the various vegetations to the 9 field rodent collection sites. The total 62 field rodents was captured by the Sherman collapsible traps from April to October 2009 at the Jangseong of Jeonnam Province, Korea. The trapping rate of the field rodents by the different collecting sites was dominant at subside storage water (24%), bush near by dam (22%), bank around field (20%), followed by 18% of grassy field and surround cattle shed. The distribution of chigger mites by the different collecting sites was the highest at Bush near by dam (28.7%). And the sites of subside storage water, bank around field and surround cattle shed were 20.4%, 18.8%, 16.4%, respectively. On the other hand the collecting sites of stream bank and ridges between rice paddies were not collected. The temperature to the collecting sites was showed $24.1^{\circ}C$ in June and $24.2^{\circ}C$ in October which was higher than April ($10.6^{\circ}C$), whereas lower than May ($25.3^{\circ}C$) and September ($26.8^{\circ}C$). The highest number of mites was collected at $24.2^{\circ}C$ and 46.6% relative humidity in October. The chigger mites and field rodents were highly collected between 18 and 24% at the sites where are loosely in the superficial layers of the soil from 8.0 cm to 10.2 cm. Total 25 species of vegetation were distributed at the collecting sites. In the present study, strong evidence was found that bank around field and grassy field were provided for the prevalence sites of tsutsugamushi disease.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.4
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• pp.364-371
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• 2020

The Korea Centers for Disease Control and Prevention is conducting surveillance of climate change vectors across all regions in Korea to counteract the spread of these vectors. As a part of this surveillance project, wild rodents were captured using traps to investigate the spread of chigger mites, the vector of Tsutsugamushi disease, across Jeonbuk, Jinan region, and to conduct studies on pathogens. Twenty samplers were used to sample chigger mites weekly from September to November in four different locations. Six hundred and eleven chigger mites of eight varying types were captured. The largest number of captured chigger mites was N. tamiyai, with 434 samples (71.0%). With the addition of 66 wild rodents captured from traps, 3,050 chigger mites were sampled, which yielded a Chigger index of 46.2. The monthly Chigger index was highest in November with a value of 206.1. the result of the test conducted in the presence of pathogens showed two positive results, each from May and September, out of all 85 pools. This result was aligned with the increased frequency in tsutsugamushi disease cases in spring and fall seasons.

• Journal of Mushroom
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• v.15 no.4
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• pp.254-258
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• 2017

Mushroom mites have recently caused severe damage to sawdust beds, mushroom mycelia, and fruiting bodies; therefore, they have reduced the production of the button mushroom, Agaricus bisporus, in greenhouses. There are currently no registered pesticides for mushroom mites. It is necessary to selectively control mushroom flies and mites without affecting the growth of the mushroom. We examined biological control of mushroom mites using predatory mite Stratiolaelaps scimitus in button mushroom cultivation. As a result, a three times treatment (1 treatment after water cleaning, 1 treatment after fungus inoculation, and 1 treatment before or after casing) was most effective at controlling mushroom mites, with 3.000 predatory mites (3 bottles) scattered evenly over $165-230m^2$ every 1-2 m. Predatory mite Stratiolaelaps scimitus could control mushroom flies and mites at the same time and could be used at any time during cultivation.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.4
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• pp.317-325
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• 2021

In order to monitor the occurrence of chigger mites, collectors were installed at four places: rice field, field, waterway, and grass field. Totally, 207 chigger mites belonging to 7 species were collected. Starting with 2 mites in the 5 weeks of September, a maximum of 49 mites were collected during 3 weeks of November. Totally, 81, 52, 47 and 27 mites were collected from grass field, waterways, rice field, and field, respectively. Analysis of sampling and collecting chigger mites determined that the most encountered species was Neotrombicula kwangneun (73, 35.3%), followed by Leptotrombidium palpale (46, 22.2%), N. tamiyai (41, 19.8%) and N. asakawai (27, 13.0%). The grab results of 44 wild rodents revealed Apodemus agrarius (35, 79.5%), Crocidura spp. (5, 11.4%), Craseomys regulus (2, 4.5%), and A. peninsulae (2, 4.5%; which had not been detected previously). A total of 6,628 chigger mites were collected from rodents, and the chigger index was determined to be 150.6. Chigger index was found to be highest at 234.2 in October, followed by 223.3 in November, 75.6 in April, and 66.2 in May. PCR from all chigger mite samples tested negative for the Tsutsugamushi pathogen.

• The Korean Journal of Soil Zoology
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• v.11 no.1_2
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• pp.16-19
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• 2006

A checklist on 61 species of chigger mites belonging to 12 genera and 2 families from Korean peninsula is suggested with Korean names of each taxon.

• The Korean Journal of Soil Zoology
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• v.3 no.1
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• pp.42-49
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• 1998

In this list, a total of 149 species balonging to 109 genera under 61 families of oribatid mites were contained to the fauna of Mt. Jiri.

• Journal of the korean veterinary medical association
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• v.17 no.6
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• pp.10-16
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• 1981

This work was intended to enhance diagnostic probability by the detection of eggs, not only mites, from the scrapings of skin lesions in three pigs infested with Sarcotes scahiei var suis, and the results were summarized as follows. 1. The amount of solve

• 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.

• Korean journal of applied entomology
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• v.57 no.4
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• pp.253-260
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• 2018

A mass-rearing method for a soil-dwelling predatory mite Stratiolaelaps scimitus (Womersley) was developed using the double box system. The rearing box consists of two, outer (22 L, $54{\times}36{\times}18cm^3$) and inner (6.5 L, $31{\times}22{\times}11cm^3$), plastic boxes. Inner box was filled with chaff (rice husks) which is used as the shelter of the predatory mites. Outer box contained 1 L of water and the inner box, then covered with a lid. This system prevents the predatory mites from escaping as well as keeping moisture of the shelter. In addition, Tyrophagus putrescentiae (Schrank), as prey mites of S. scimitus, was reared on the rice bran as a food source using the same double box system. The both mites were reared at $25{\pm}1^{\circ}C$, $60{\pm}10%$ relative humidity condition. The prey mites were provided once a week. The density of predatory mites increased three times for four weeks and the final population was approximately 120,000 individuals/box (4 L). This is a simple mass-raring technique of S. scimitus and helpful for the biological control of soil pests.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.185-195
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• 2003

Phytoseiid mites are important predators of spider mites, rust mites and many of insect pests as well. From two-year (2001-2002) survey of apple orchards in Kyoungbuk and Suwon area, 13 species of phytoseiids, 12 species of the genus Amblyseius and one species of the genus Typhlodromus were found. Among them, Amblyseius womersleyi was the most dominant followed by A. rademacheri, A. orientalis, and A. makuwa. Amblyseius rademacheri and A. makuwa were mainly found from ground vegetation. Keys to genera and species were presented with some pictorial details and ecological notes of each species. Further discussion on systematics of the family Phytoseiidae and use in apple IPM were suggested.