• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.177-187
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• 2005

For the comparison of feeding behavior of Nilaparvata lugens among different rice varieties, electrical penetration graph (EPG) technique was used. Ten rice varieties were selected from national-widely recommended rice varieties cultivating in Chungnam province. The correlation between feeding duration and honeydew amount excreted was investigated, and the types of EPG pattern were analyzed among rice varieties. The EPG patterns divided into 6 types according to electrical specific feature, respectively. Type 1 pattern was a searching feeding sites, resting or wandering on a rice plant. Type 2 pattern was appeared when the insect untaken from phloem sieve element. Type 3 pattern was observed when the insect piercing into the rice plant. Type 4 pattern was observed when the insect salivating in rice plant. Type 5 pattern was observed when the insect ingesting from the xylem. Type 6 pattern was observed when the stylet moving in cell. Feeding duration time on Gum-nam was significantly shorter than Dong-jin, Dae-ahn, Dong-ahn, Dae-san. Also, on Gun-nam, it was shown that the brown planthopper did not penetrate the cuticle for a long time. The total number of excreted honeydew droplets by the brown planthopper was the greatest in Dong-jin variety and the least in Gum-nam variety. In proportion to phloem feeding time, the number of honeydew droplets had been increased. According to the results of EPG patterns and honeydew droplets analysis, N. lugens seems to prefer Dong-jin, Dong-ahn, Dae-san, and Dae-ahn to Gum-nam, Da-san, and Nam-chun rice plant variety.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.351-358
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• 2016

Consistent with a previous study on the brown planthopper Nilaparvata lugens (BPH) (Seo et al., 2009), we identified seven distinct EPG waveforms (np, L1, L2, L3, L4-a, L4-b, and L5) in adult female Laodelphax striatellus (SBPH) that fed on rice plants, by using the direct current electrical penetration graph (DC-EPG) system. The shape of waveforms and the pattern of occurrence of each waveform of SBPH were very similar to those of BPH. L3 and L4-a always occurred prior to L4-b. Periodical honeydew excretion was observed in L4-b only. Microsection observation following laser stylectomy revealed that the tips of SBPH stylets severed in L3, L4-a, and L4-b were commonly located in or near the phloem region of rice plants, but were located in the xylem in L5. Plant sap flowed from the stylets severed in L4-b only, and its main carbohydrate component was detected as sucrose by HPLC analysis. These results and the patterns of EPG waveform progress in SBPH suggested that feeding activities on rice plant tissue were relevant to each EPG waveform. L1 and L2 corresponded to the initiation of stylet penetration and stylet movement with salivation on the outside of the vascular bundle. L3 and L4-a were related to feeding activities within the phloem region in preparation for phloem sap ingestion. L4-b was closely associated with phloem sap ingestion, and L5 corresponded to xylem feeding behavior.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.7 no.3
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• pp.81-91
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• 1986

진딧물은 아주 작고 연약하여 조그마한 힘을 가해도 곧 터져버릴 것 같은 곤충이지만, 일생을 통하여 5가지 형태로 까지 변화할 수 있어 불량환경에 적응할 수 있는 힘은 그 어느 곤충보다도 크다고 하겠다. 처녀생식으로 번식하므로 번식력 또한 대단하여 그 숫자가 단시일내에 크게 불어나는 해충이다. 과수 재배시에 진딧물의 피해양상은 과수의 영양분을 흡즙하고, 감로를 분비하여 그을음병을 유발시키며, 잎을 오그라뜨리거나 뒤쪽으로 말리게하여 잎의 기능을 억제시킴으로써 과수의 생육을 지연시키고 묘목의 경우에 심할 때는 고사(枯死)까지 한다. 또한 최근에는 약제방제시에 약제선택성이 강한 종들이 나타나고 있는 실정이므로 진딧물의 효과적인 방제를 위해서는 무엇보다도 먼저 진딧물의 종류에 따른 생태를 잘 알고 그에 따른 합리적인 방제대책을 수립하여야 할 것으로 생각된다. 이에 필자는 그동안의 연구에서 얻어진 결과를 토대로 과수가해 주요 진딧물의 생태와 방제법을 소개하는 것이며 이 조그마한 자료가 진딧물에 얽힌 문제점들을 해결하는데 조금이나마 도움이 되었으면 한다.

• Journal of Korean Medicine for Obesity Research
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• v.18 no.2
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• pp.152-158
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• 2018

The purpose of this study was to investigate the effects of modified fasting therapy using Gamrosu and herbal medicine on the changes of body compositions in women. We analyzed the medical records of 11 patients, who carried out modified fasting therapy at Dunsan Korean Medicine Hospital of Daejeon University. Body compositions (body weight, body mass index, body fat mass, skeletal muscle mass, basal metabolic rate, extracellular water ratio, abdominal circumference, thickness of abdominal subcutaneous fat, visceral fat area) were reviewed before and after modified fasting therapy. The body composition values (body weight, body mass index, body fat mass, skeletal muscle mass, basal metabolic rate, extracellular water ratio, abdominal circumference, thickness of abdominal subcutaneous fat, visceral fat area) decreased after modified fasting therapy. Results from this investigation showed that modified fasting therapy using Gamrosu and herbal medicine has positive effects on changes of body compositions.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.95-104
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• 2013

This research was performed to test the effects of oleic acid for the management of greenhouse whiteflies and tobacco whiteflies. Tobacco whiteflies, especially, are the vectors of tomato yellow leaf curl virus on tomato plants. Whiteflies are not only the vectors of various viruses but also the major insect pests that cause direct damages through sucking and induce sooty mold with their sweet dew on tomato plants. There are many eco-friendly management measures including the use of yellow sticky trap and natural enemies such as Eretmocerus eremicus and Amblyseius swirskii. However, these management measures have difficulties to implement in the greenhouse. Therefore, in this research, oleic acid was tested for its effect on the management of whiteflies at various concentrations of 1,000ppm, 2,000ppm, or 4,000ppm. As a result, treatments of 1,000ppm, 2,000ppm and 4,000ppm oleic acid showed the control value of 70%, 76% and 84%, respectively. In another test, treatments of 2,000ppm oleic acid, and control treatment of 1,5000ppm neem oil and 50ppm dinotefuran showed the control value of 82%, 75%, and 75%, respectively. Cost for one application of oleic acid and neem oil for 10a area would be 3,180 Won and 20,150 Won, respectively. As a result, it was assumed that the use of oleic acid would be a appropriate management measure.

• Journal of Life Science
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• v.29 no.2
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• pp.202-208
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• 2019

Brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacidae), is one of the most important migratory pests damaging rice in Korea. It invades annually from tropical and subtropical areas via continental air streams. It is necessary to determine the resistance levels of rice varieties in order to control efficiency. The honeydew excretion, development, and reproduction of the migratory BPH were studied by region in a laboratory at $25{\pm}2^{\circ}C$ and $65{\pm}5%\;RH$ and a 16L: 8D photoperiodism conducted on three BPH resistant genes: Bph1, Bph2, and Bph18. The information obtained was reported using the jackknife method, and we created life table statistics accordingly. The feeding amount of Bph1 resistant gene was lower than that of resistant genes. The developmental periods of immature stages ranged from $13.7{\pm}0.10d$ on Bph2 (Namhae, 2015) to $18.5{\pm}1.06d$ on Bph2 (Sacheon, 2016). Reproductive period and female longevity were longest on the non-resistant genes, Bph2 and Bph18 (except 1980s), and the highest fecundity of N. lugens was observed on the two BPH resistant genes. Highest net reproductive rates ($R_0$) were calculated on Bph2 by region. Intrinsic rates of population increase ($r_m$) showed a difference in resistant genes by region. These population parameters showed that migratory regions and biological characteristics of N. lugens vary annually.