• Korean journal of applied entomology
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• v.42 no.3
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• pp.249-255
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• 2003

These studies were carried out to investigate fumigant, contact toxicity and repellency effects of 34 terpenes against acaricide susceptible the two-spotted spider mite, Tetranychus urticae. In addition, the efficacy was also tested against two acaricide-resistant strains. Two terpenes, isosafrole and safrole showed fumigant toxicity of 98.4%, at 10${\mu}\ell$/1 (air) concentration. LD$\_$50/ values of these two terpenes were 2.6${\mu}\ell$/1 and 4.3${\mu}\ell$l/1, respectively. Most terpenes showed low or no contact toxicity, except isosafrole showing 60.2% mortality against eggs. Hexanoic acid and limonene showed repellency effects of 79.1%, 87.8%, respectively, to the susceptible strain at concentration of 1,000 ppm in the lab conditions. Hexanoic acid (1,000 ppm) showed repellency effected of 77.8% and 83.3% to fenpropathrin and pyridaben resistant strains, respectively. However, limonene showed no repellency to the two resistant strains.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.881-891
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• 2016

The susceptibility of the predatory mite, Neoseiulus californicus to extracts of Melia azedarach, Piper nigrum, Syringa velutina and their mixtures was evaluated in laboratory bioassays. In treatments with plant extracts tested, 76-86% of adult female predators survived after 7 days after treatment. Adult female predators treated with plant extracts tested produced 68.3-81.1% as many eggs as did control females and eclosion of eggs deposited by treated predators was not affected. Moreover, treatment of plant extracts tested showed no toxic effect on N. californicus eggs and produced 100% hatchability. Survival of N. californicus nymphs was not seriously affected by exposure to the plant extracts tested. Immatures of N. californicus survived on the leaf disc treated with plant extracts tested and 78-90% of immature predators reached adulthood. These results suggest that extracts of Melia azedarach, Piper nigrum, Syringa velutina and their mixtures expected to be promising candidates for use in integrated mite management program with N. californicus.

• Parasites, Hosts and Diseases
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• v.55 no.2
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• pp.193-196
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• 2017

This study investigated the development characteristics of Dermacentor everestianus under laboratory conditions. The time taken for D. everestianus to complete the whole life cycle was 110.2 days on average, and the average developmental durations of larvae and nymphs were 17.1 days and 29.5 days, respectively. The summation of the prefeeding, feeding, and preoviposition periods of females was 17.8 days, and the oviposition and egg incubation lasted for 18.1 days and 27.7 days, respectively. A highly positive correlation was observed between the weight of engorged female and the number of egg mass laid (r=0.947). The reproductive efficiency index and the reproductive fitness index were 7.1 and 6.1, respectively.

• The Korean Journal of Pesticide Science
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• v.19 no.4
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• pp.418-423
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• 2015

Effects of 9 acaricides to the predatory mite, Neoseiulus californicus were evaluated. Seven of the acaricides tested, cyenopyrafen. spirodiclofen, spiromesifen, acequinocyl, bifenazate, flufenoxuron and cyflumetofen exhibited low toxicity to adult females and nymphs of N. californicus and had little effect on the reproduction and eclosion of eggs deposited by treated predators. Moreover, hatch percentage of N. californicus eggs was unaffected by exposure to these seven acaricides. Etoxazole did not significantly affect the survival and reproduction of adult female predators but caused very low eclosion in eggs laid by treated females and high egg mortality. Pyraclofos was extremely toxic to adult female predators and caused 100% mortality. Adult female predators survived on a diet of spider mites treated with cyenopyrafen. spirodiclofen, spiromesifen, acequinocyl, bifenazate, flufenoxuron and cyflumetofen and their fecundity was not substantially affected. Based on the results, cyenopyrafen. spirodiclofen, spiromesifen, acequinocyl, bifenazate, flufenoxuron and cyflumetofen are appeared to be promising candidates for use in integrated mite management program where N. californicus is the major natural enemy.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.105-109
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• 2001

Dispersion pattern of the citrus red mite (CRM), Panonychus citri (McGregor) was determined to develop a monitoring method in the satsuma mandarin fields, Citrus unshiu L., in Jeju-do, during 1999 and 2000. CRM population was sampled by collecting leaves. Taylor's power law provided better description of mean-variance relationship for the dispersion indices compared to Iwao's patchiness regression. Slopes and intercepts of Taylor's power law from leaf samples did not differ among surveyed groves. Fixed-precision levels (D) of a sequential sampling plan were developed using Taylor's power law parameters generated from all motile stages of CRM in leaf sample. This sampling plan for leaf sample estimate was tested with resampling validation for sampling plan using 4 independent data sets. Resampling simulation analysis demonstrated that actual fixed-precision level values were better than desired D values of 0.20, 0.25 and 0.30. Required numbers for tree sampling at the density of more than 7 mites per tree were fewer than 18.

• Journal of Ecology and Environment
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• v.34 no.3
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• pp.307-313
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• 2011

Although lizards are important hosts for hard ticks (Ixodidae), very few studies have been conducted in South Korea. To determine whether or not hard ticks can infest lizards endemic to South Korea, we examined 77 lizards of four species (Eremias argus, Sincella vandenburghi, Takydromus amurensis, and Takydromus wolteri) that were collected at 22 different sites between April and October 2010. We confirmed that all four lizard species can be infested by Ixodes nipponensis larvae or nymphs. Of the 62 E. argus examined, we found an average of 12.5 larvae on two lizards and an average of one nymph on one lizard. We found seven nymphs on one S. vandenburghi. We found an average of two nymphs on two of the five T. amurensis and an average of one nymph on four of the nine T. wolteri. Ixodes nipponensis larvae and nymphs were found most frequently on the foreleg axillae (87.8%), followed by the forelegs (7.3%), the eyelids (2.4%), and the ears (2.4%) of the lizards. To the best of our knowledge, this is the first report of I. nipponensis infestations of lizards endemic to South Korea.

• The Korean Journal of Ecology
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• v.23 no.2
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• pp.107-112
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• 2000

Comparison of oribatid mite community structures among Namsan, Kwangreung, and Mt, Jumbong, which receive different levels of environmental stress from severe to almost none, was made in coniferous and deciduous forests, respectively. The number of species of oribatid mites was significantly lower in Namsan and Mt. Jumbong than in Kwangreung in the coniferous forest (p<0.05). In the deciduous forests, the number of species of oribatid mites was significantly lower in Namsan than in Kwangreung and Mt. Jumbong. Dominant species in 3 regions were remarkably different. Similarity of the oribatid community between Namsan and Kwangreung was much higher (ca. 2 times) than similarities between Namsan and Mt. Jumbong. and Kwangreung and Mt Jumbong. Diversity index (H$^{\prime}$) value of oribatid communities in deciduous forests in Namsan, Kwangreung and Mt. Jumbong was 2.74, 2.78, and 2.87, respectively. Diversity (H$^{\prime}$) value of oribatid communities in coniferous forests in Namsan, Kwangreung and Mt. Jumbong was 2.83, 2.62, and 2.38, respectively. Namsan and Kwangreung were characterized as O-type in both coniferous and deciduous forests On the contrary, Mt. Jumbong was characterized as MG-type in MGP-I analysis.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.191-197
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• 2018

Mites in the family Ascidae are soil dwelling predators of small insects which would have potential to be used as biological control agent. In Korea, 10 genera of 24 species were recorded in the family. During the soil acarine biodiversity study, Asca bicornis Canestrini & Fanzago, 1877 was discovered from moss habitat on Muljangori craer lake 936 m alt in Hallasan mountain in Jeju which was designated as UNESCO Biosphere reserve and World herigate site. We reports this as a new record to Korean Mesostigmata fauna, and provide the morphological description. This species has morphologically characteristic as all dorsal setae nude and needle shaped, lateral caudal projection of Z4 shaped, which are different from the con-general species of A. aphidioides.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.120-126
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• 1995

This study investigated the soil oribatid mite community at planatations of the Korean white pine, planted in different years. The soil samples $(10\times10\times5cm)$ were taken monthly from Jun 1988 to July 1989, and soil microarthropods in th sample were extracted using the Tullgren funnel for 72 hors. The diversity indices decreased at the older plantation sites with the maximum point in January and the minimum in September. The richness indices showed the maximum point in June and the minimum in may. The dominance indices increased at the older plantation and showed the maximum point in April, May, the minimum in January. The indices of aggregation of Oribatid mites species showed concentrated distribution in the average 1.9. The older plantation, the more indices increase. The seasonal variation of th indices tended to be greatest in April, August and at lowest in January. The richness indices was positively correlated with shannon-wiener, evenness indices. The dominance, aggregation indices was negatively correlated with shannon, evenness, richness indices.

• Parasites, Hosts and Diseases
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• v.53 no.6
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• pp.789-793
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• 2015

In order to explore tick proteins as potential targets for further developing vaccine against ticks, the total proteins of unfed female Dermacentor silvarum were screened with anti-D. silvarum serum produced from rabbits. The results of western blot showed that 3 antigenic proteins of about 100, 68, and 52 kDa were detected by polyclonal antibodies, which means that they probably have immunogenicity. Then, unfed female tick proteins were separated by 12% SDS-PAGE, and target proteins (100, 68, and 52 kDa) were cut and analyzed by LC-MS/MS, respectively. The comparative results of peptide sequences showed that they might be vitellogenin (Vg), heat shock protein 60 (Hsp60), and fructose-1, 6-bisphosphate aldolase (FBA), respectively. These data will lay the foundation for the further validation of antigenic proteins to prevent infestation and diseases transmitted by D. silvarum.