• Korean Journal of Veterinary Research
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• v.21 no.2
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• pp.123-133
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• 1981

진드기는 생물학적(生物學的) 여러 분야(分野)의 연구대상(硏究對象)으로 또는 진드기 매개전염병(媒介傳染病)의 역학(疫學)과 방제(防除)를 위(爲)한 연구재료(硏究材料)로 공시(供試)되는데, 이를 위(爲)하여는 실험작군(實驗作群)에 의(依)한 집단생산(集團生産)이 요구(要求)된다. 그러나 이러한 실험작군(實驗作群)에 있어서 동일(同一)한 가토(家兎)를 실험용(實驗用) 숙주(宿主)로 반복(反復)하여 사용(使用)했을 경우(境遇), 진드기의 흡혈성취도(吸血成就度)가 저하(低下)되는 현상(現象)을 경험(經驗)하게 된다. 이러한 현상(現象)에 흥미(興味)를 가지고, 이를 실험용(實驗用) 가토(家兎)에 대(對)한 Haemaphysalis longicornis 미포혈(未飽血) 자충(雌蟲)의 반복흡혈(反復吸血)에 있어서의 흡혈성취도(吸血成就度) 변화(變化)를 조사(調査)해 보고자 몇가지 실험(實驗)이 설계(設計) 진행(遂行)된 바, 결과(結果)는 다음과 같이 요약(要約)된다. 1. 최초(最初)(1차(一次)) 흡혈시도(吸血試圖)에 있어서 공시(供試)된 진드기의 흡혈성취도(吸血成就度)는 실험용(實驗用) 숙주(宿主)인 가토(家兎)의 월령별(月齡別) 비교군간(比較群間)에 유의성(有意性) 있는 차이(差異)가 인정(認定)되지 아니 하였다. 2. 성공적(成功的) 흡혈율(吸血率)은 최초(最初)(1차(一次)) 흡혈시도(吸血試圖)에서 82.29%를 보였으나, 반복흡혈시도(反復吸血試圖) 차수(次數)가 증가(增加)함에 따라, 76.04%(2차(二次)), 53.13%(3차(三次)), 50%(4차(四次)), 46.87%(5차(五次))로 점차적(漸次的)으로 저하(低下)되는 성적(成績)을 보였다. 3. 평균흡혈기간(平均吸血期間)은 최초(最初)(1차(一次))흡혈시도(吸血試圖)에서 9.34일(日)을 보였으나, 반복흡혈시도(反復吸血試圖) 차수(次數)가 증가(增加)함에 따라, 9.74일(日)(2차(二次)), 10.31(日)(3차(三次)), 10.42(日)(4차(四次)), 10.47(日)(5차(五次))로 점차(漸次) 지연(遲延) 되었으며, 평균흡혈속도(平均吸血速度)는 0.1070에서 0.1027, 0.0970, 0.0960, 0.0955로 점차(漸次) 감속화(減速化) 되었다. 4. 평균(平均) 흡혈체중(吸血體重)에 있어서는 최초(最初)(1차(一次)) 흡혈시도(吸血試圖)에서 253.3mg의 성적(成績)을 보였으나, 흡혈시도(吸血試圖)가 반복(反復)됨에 따라, 242.58mg(2차(二次)), 190.73mg(3차(三次)), 187.85mg(4차(四次)), 184.18mg(5차(五次))으로 점차(漸次) 경량화(輕量化)되는 경향(傾向)을 나타냈다. 5. 결론적(結論的)으로 실험용(實驗用) 가토(家兎)에 대(對)한 Haemaphysalis longicornis 진드기의 흡혈성취도(吸血成就度)는, 반복흡혈시도(反復吸血試圖) 차수(次數)가 증가(增加)함에 따라, 숙주체내(宿主體內)에 형성(形成) 누적(累積)되는 진드기에 대(對)한 획득면역(獲得免疫)의 영향(影響)을 받아 점차(漸次) 저하(低下)되며, 따라서 H. longicornis 진드기의 집단생산(集團生産)을 위(爲)한 실험작군(實驗作群)이나 혈류보존(血統保存)을 위(爲)한 계대흡혈(繼代吸血)에 있어서 동일(同一) 가토(家兎)를 2회이상(回以上) 반복사용(反復使用)하는 것은 바람직한 일이 아닌 것으로 사료(思料)된다.

• Parasites, Hosts and Diseases
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• v.30 no.4
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• pp.341-348
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• 1992

Because no reference on trombiculid mites (Acarina: Trombiculidae) in Cheju Island where tsutsugamushi disease is highly endemic had been available, studies on trombiculid mites in Cheju Island were implemented during the period of August 1991-Apil 1992, and the results obtained are summarized as follows: (1) The species and numbers of the field rodents collected were 143 Apodemus agrarius chejuensis (92.3%), 11 Crocidura lasiura (7. l%) and 1 Micromys minutus (0.6%) From total 12,075 chiggers harvested, 9 species of 4 genera in Trombiculidae were identified. (2) The predominant species through all seasons was 1. setum (43.3%), followed by 1. orientale (27.4%) and 1. scutellare (26.6%). However, in autumn when the most cases of tsutsugamushi disease occur, 1. scutellere was prominently predominant, having 79.8% of the collected chiggers. (3) Among 1,1421. scutellare examined for Rickettsia tsutsugpmushi by means of IFA test, 6 individuals were found positive showing 0.5% of infection rate. This is the first finding that 1. scutellere is the second vector species of tsutsugamushi disease in Korea. (4) Antibody positive rate of A. agrarius chejuensis sera were 31.2% (44/139), and 1 M. minutes serum was also found positive. The seropositive rates by season were not so significantly different. Key words: Tsutsugamushi disease, epidemiology, vector species, Cheju Island, Korea.

• Korean journal of applied entomology
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• v.33 no.4
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• pp.230-236
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• 1994

Dicofol susceptible two-spotted spider mite(S) which was selected by 150 times of dicofol treatment showed 27 5-fold increase in resistance as compared to S strain. Inheritance of resistance and crossresistance in selected strain($R_d$) were investigated. There were differences oi susceptibility in the dicofol concentmtion-moltaliity relationships between $F_1$ progenies (R♀, XS♂, R♂, XS♀) obtained from reciprocal cross with the S strain and $R_d$, strain. Degree of dominance of the $F_1$ progenies (R♀, XS♂, R♂, XS♀) were -0.29 and -0.72 in adult females and -0.42 and -0.93 in adult males, respectively. These results suggest that inheritance of dicofol resistance is controlled by an incomplete recessive. $R_d$ strain exhibited a high level of cross resistance to amitraz, and also showed cross resistance to pyrethrotd acaricides, acrinathrin and bifenthnn. $R_d$ strain showed non-cross reslstancz to abamectin, chlolfenson, clofentezine, cyhexatm, fenbutatin oxlde, fenpyroximate, hexythiazox, monocrotophos, propargite and tetradifon, but negatively correlated cross-resistance to azocyclotin and fenbutatin oxide belonging to tin acaricides.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.491-495
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• 2014

Mites were collected from organic cultivations of greenhouse cucumbers and identified as Tyrophagus neiswanderi (Acari: caridae). T. neiswanderi (length, $490.1{\mu}m;$ width, $288.1{\mu}m$) is a very small, milky-white, and egg-shaped mite, and it mainly causes damage to the leaves, flowers, and fruits of cucumber plants. In the early growing season of cucumbers, the shoots of seedlings became pale and yellow because of T. neiswanderi, and eventually shrinkage or bud-failing was observed in the plants. In the middle of the growing season, T. neiswanderi caused white spots on the leaves and flowers of the plants, and the spots gradually became holes. T. neiswanderi also caused severe damage to young fruits by feeding on the rinds of the fruits, inducing malformations and lowering the economic value.

• Journal of Forest and Environmental Science
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• v.13 no.1
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• pp.51-56
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• 1997

Developmental characteristics and reproductive ability of Caloglyphus sp. were examined under the constant temperature conditions. This mites has five stages ; egg, larva, protonymph, deutonymph and adult. All active instars preyed on larvae of pine gall midge, Thecodiplosis japonensis Uchida et Inouye. The developmental period from the egg to the adult decreased with temperature increase at a range between $15^{\circ}C$ and $30^{\circ}C$. The threshold of temperature and the thermal constant for the development from the egg to the adult were $8.2^{\circ}C$ and 122.0 day-degrees, respectively. At $25^{\circ}C$, survival rate from egg to deutonymph was estimated as 66.4%, and longevity of the adult was 12.3 days for male and 10.0 days for female. After a preoviposition period of 1 and 2 days female laid an average of 360.6 eggs each, almost all during the first half of their life time. The value of the net reproduction(Ro), the mean length of a generation(T) and the intrinsic rate of natural increase($r_m$) were calculated as 101.1, 9.3 days and 0.494 per female per day, respectively.

• 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.50 no.3
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• pp.235-245
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• 2011

Temperature-related parameters of Panonychus citri (McGregor) (Acarina: Tetranychidae) development were estimated and a stage-structured matrix model was developed. The lower threshold temperatures were estimated as $8.4^{\circ}C$ for eggs, $9.9^{\circ}C$ for larvae, $9.2^{\circ}C$ for protonymphs, and $10.9^{\circ}C$ for deutonymphs. Thermal constants were 113.6, 29.1, 29.8, and 33.4 degree days for eggs, larvae, protonymphs, and deutonymphs, respectively. Non-linear development models were established for each stage of P. citri. In addition, temperature-dependent total fecundity, age-specific oviposition rate, and age-specific survival rate models were developed for the construction of an oviposition model. P. citri age was categorized into five stages to construct a matrix model: eggs, larvae, protonymphs, deutonymphs and adults. For the elements in the projection matrix, transition probabilities from an age class to the next age class or the probabilities of remaining in an age class were obtained from development rate function of each stage (age classes). Also, the fecundity coefficients of adult population were expressed as the products of adult longevity completion rate (1/longevity) by temperature-dependent total fecundity. To evaluate the predictability of the matrix model, model outputs were compared with actual field data in a cool early season and hot mid to late season in 2004. The model outputs closely matched the actual field patterns within 30 d after the model was run in both the early and mid to late seasons. Therefore, the developed matrix model can be used to estimate the population density of P. citri for a period of 30 d in citrus orchards.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.153-163
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• 2020

This study was conducted to evaluate the fitness of Tetranychus kanzawai Kishida on different host plants: young and old leaves of the mandarin orange 'shiranuhi' ((Citrus unshiu × C. sinensis) × C. reticulata), Japanese violet (Viola japonica Langsd.) and kidney bean (Phaseolus vulgaris L.). The development and oviposition experiments were conducted at constant temperatures (20, 25 and 30℃) and a life table parameters were estimated. T. kanzawai could complete it's development on 'shiranuhi' young leaves, japanese violet and kidney bean, while all died during the immature period on 'shiranuhi' old leaves. The total developmental period of T. kanzawai feeding on 'shiranuhi' young leaves was 17.4, 13.4 and 10.2 days at each temperature, respectively, which was longer than 16.1, 9.5 and 7.0 days of kidney bean. The female longevity of T. kanzawai on young leaves of 'shiranuhi' were 19.1, 15.0 and 12.3 days at each temperature, respectively, and there was no significant difference from 22.1, 14.1 and 10.9 days investigated from kidney bean. The fecundity was 18.1, 23.9 and 17.8 eggs per female, which was less than them of japanese violet and kidney bean at each temperature, respectively. As a result of estimating the life table parameters based on the experimental data, intrinsic rate of increase (r_m) were significantly different from each other, and appeared in the following order: kidney (0.1542, 0.2563 and 0.3251), japanese violet (0.1087, 0.2007 and 0.2673) and 'shiranuhi' young leaves (0.0868, 0.1002 and 0.1217) at each temperature, respectively. Finally, the management strategy against T. kanzawai in citrus orchards was discussed based on the results.