• Korean journal of applied entomology
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• v.13 no.4 s.21
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• pp.205-208
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• 1974

This survey was carried out in order to find out population density of aphid at the alpine area. Thetraps were set from May 1 to October 31 in 1973. The summarized results are as follows; 1. About 37 species of aphids were trapped, including 4 species of potatao virus vectors. 2. Of these, dominant species are Aphis gossypii Koch, Aphis lerodendri Matsumura, and Lipahis erysimi Kaltenbaeh. The $67\%$ of 3, dominant species consisted of the trapped total aphids. 3. The potato virus vectors are Myzus persicae Sulzer, Aulacorhum solani Kaltenbach, Lipaphis erysimi Kaltenbaeh and Aphis gossypii Glover. 4. Tile number of aphids and vectors at the alpine area is considerably lower than that at the level land. 5. The peak of the flying aphid occurrence is shown in the latter part of September.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.407-411
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• 2008

This study was conducted to estimate the economic injury level (EIL) and economic threshold (ET) of the green peach aphid, Myzus persicae, on Chinese cabbage (Brassica campestris var). The changes of biomass of Chinese cabbage and M. persicae density were investigated after introduction of M. persicae at different density (0, 2, 5, 10, 15, and 20 per plant; inoculated at 10d after planting). The densities of M. persicae largely increased from the above initial densities to 0, 92.3, 177.4, 406.9, 440.4, and 471.3 aphids per plant at 18d after the initial inoculation, respectively. The biomass of Chinese cabbage significantly decreased with increasing the initial inoculated density of M. persicae: 602.0, 264.2, 262.0, 109.3, 151.0, and 67.3 g in above plots with different initial densities, respectively. The relationship between cumulative aphid days (CAD) and yield loss (%) of Chinese cabbage was well described by a nonlinear logistic equation. Using the estimated equation, EIL of M. persicae on Chinese cabbage was estimated 25 CAD per plant based on the yield loss 13%, which take into account of an empirical gain threshold 5% and marketable rate 92% of spring Chinese cabbage. Also, ET was calculated at 80% of EIL: 20 aphids per plant. Until a more elaborate EIL-model is developed, the present result may be useful for M. persicae management at early growth stage of Chinese cabbage.

• Korean journal of applied entomology
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• v.8
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• pp.7-9
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• 1969

거의 모든 국가에서 생산된 씨감자는 감자바이러스 이병율을 검사해서 합격품만을 농민에 분배하고 있다. 우리나라는 딴 씨감자 생산국과는 사정이 달라 고령지에서 씨감자를 생산하고 있는 관계로 감자밭의 필수는 전국적으로 막대한 수에 달한다. 우리나라에서의 감자바이러스 김정은 원원종에 한하고 있으나 농민에 분배되는 씨감자도 바이러스 검정을해서 합격품만을 나누어주어야 국가의 체면이 서겠다. 그러나 현재의 시설로는 이를 감당 할 수 없어 이에 대치 될 만한 실제적 방법의 하나로 매개진딧물 밀도와 감자바이러스 이병율간의 상관관계를 밝혀 번잡한 바이러스 검정법 대신 매개진딧물의 공중밀도를 조사하여 해지점의 감자바이러스 이병율을 추산 할 목적으로 본 시험에 착수하였다. 본 보고에서는 진딧물조사 결과만을 발표하고 18개소에서 행한 포장시험결과는 1970년에 행할 바이러스 검정을 마치면 종합결과를 발표 할 예정이다. 표 1에서와 같이 서해안, 내륙, 및 대관령에서의 매개진딧물과 일반진딧물의 수는 각각 8/31, 179/680 및 50/237이었으며 필자가 행한 1967, 1968년의 조사성적을 뒷받침하는 결과를 얻었다. 이에 필자는 씨감자 부족량 약 60,000톤의 조속한 충족을 위해 씨감자의 증식 단계에서는 서해안 일모작 답을 환용 할 것을 다시 한번 강조하는 바이다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.3
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• pp.35-40
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• 1980

In order to evaluate the fluctuation of soybean aphid (Aphis glycines Matsumura) population, six leading soybean cultivars were planted on five different planting dates with three plant spacings. The survey of aphid population and climatical condition were made from June through September in 1978. According to the differences of planting dates and plant spacings the soybean aphid populations were varied, and varietal response to the aphid was significantly different. Counting of aphid infestation on top third trifoliolate leaf seemed to be efficient for the estimation of soybean aphid population.

• Journal of Bio-Environment Control
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• v.13 no.1
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• pp.16-20
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• 2004

Aphis gossypii Glover(Homoptera: Aphididae) is an serious pest on various crops. This experiment was conducted to evaluate the effect of A. gossypii Glover on the growth of oriental melon and the plant recovery after removing A. gossypii. Visible damage symptom caused by A. gossypii feeding to oriental melon was leaf distortion and stunting. A. gossypii feeding for 20 days on oriental melon significantly reduced the growth of oriental melon with increasing A. gossypii density level. Plant growth was decreased by 63${\sim}$69%, 62${\sim}$88% and 49${\sim}$70% in plant height, leaf area and dry weight, respectively. During 10 day after aphids removal, the infested leaves remained stunt, however, new shoot and leaf recovered gradually. By 20 day, plant height, leaf area and dry weight substantially increased in 5 aphid per plant. Plant recovered rapidly with day and among aphid density level, 5 aphid per plant showed rapid recovery. When plant were infested with several density of aphid per plant, sugar contents of total leaves were not significantly different between aphid density level. Whereas, sugar contents of lear infested with aphid per leaf were decreased with increasing cumulative aphid-days.

• Korean journal of applied entomology
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• v.25 no.4 s.69
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• pp.209-213
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• 1986

Dominant aphid species and seasonal fluctuations of the colonizing aphids on apple tree, peach tree, and pear tree were examined without insecticide treatment during $1982{\sim}1984$ in Suweon. The dominant species among the colonizing aphids in each fruit tree were Myzus malisuctus in April-June and Aphis citricola in Aug.-Oct. on apple tree; Myzus persicae in early springtime and Hyalopterus pruni in May-Oct. on peach tree; Sappaphis piri in April-June, Oct. and Aphis citricola in July-Sept. on pear tree. M. malisuctus and A. citricola on apple tree showed 3 peaks a year; the former was early June, late Aug. and early Oct., the latter early June, middle Aug. and late Sept. M. persicae on peach tree showed peak on late May to early June, and H. pruni on middle June and middle Oct. S. piri and A. citricola on pear tree showed 2 peaks a year; the former was late May and late Oct., the latter early June and early Sept.

• Korean journal of applied entomology
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• v.39 no.4
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• pp.251-258
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• 2000

These studies were conducted to investigate the prey consumption and suppression of cotton aphid and green peach aphid by Chrysopa pallens Ramber as a predator. The 3$^{rd}$ instar of C. pallets fed on 29.8, 77.9, 133.6, and 155.7 individuals of apterous Aphis goussypii Glover a day at 17,22, 27, and 32$^{\circ}C$, respectively. A preovipositing female fed on 73.1 individuals, ovipositing female on 86.6 individuals, and adult male on 69.7 individuals of apterous Myzus persicae (Sulzer) a day at the 27$^{\circ}C$. The functional response curve of the larvae and adults of C. pallens to the densities of A. gossypii indicated Helling’s Type II: the consumption of prey by the C. pallens increased with the prey density but the consumption rate decreased. The attack rate of 3rd instar of C. pallens was the highest among the 2nd instar, 3$^{rd}$ instar, adult male and adult female, and handling time was the shortest. The critical ratio of the predator vs. the prey to effectively suppress the population of A. gossypii by releasing C. pallets eggs was 1 : 4 on red pepper and egg plant, and 1 : 3 on cucumber. Release of second larval stave of C. pallens at the ratio of 1 : 30 of the predator vs. the prey controlled satisfactorily A. gossypii on red pepper, and 1 : 20 on cucumber and tomato. The three-times introduction of the eggs of C. pallens was as effective as four applications of insecticides from mid-June to late September.r.

• Korean journal of applied entomology
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• v.23 no.1 s.58
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• pp.28-36
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• 1984

The relationship between ratio of virus diseases and the population of aphid vectors was studied by planting radishes(Rophanus sativus L. var. Chungsu gungjung) every 10 days and collecting aphids from April to November at Jeonju, Korea in 1982. Alate aphids were collected with yellow pan traps and virus infection ratios were checked with symptoms. The populations of flying aphids showed two peaks, one in the late May and one in the middle October in Jeonju and the population of aphid vectors also showed the same inclination. Of aphid vectors, Myzus persicae, Lipaphis erysimi, Brevicoryne brassicae, and Aphisgossypii were trapped and their percentages to total trapped aphids were $62.82\%(39,260/62,499)$ M. persicae was the most prevalent species and its percentages to aphid vectors were $82.53\%(32,401/39,260)$. High and sudden increase in virus infection ratio was found in spring while the trend in autumn was slow and low. A correlation coefficient between the population of virus vector aphid and virus infection ratio was $r=0.7414^*(\hat{Y}=8.1444+0.0551X)$ in spring and $r=0.9117^{**}(\hat{Y}=10.2590+0.463X)$ in autumn. The symptoms of radish virus diseases appeared approximately 15 days after virus vector aphids had attacked. Virus infection ratios were higher on plots where virus infected plants were reserved than on plots where they were removed.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.44-49
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• 2001

Development and predation of an aphidophagous gall midge, Aphidoletes aphydimyza (Rondani) , on the green peach aphid, Myzus persicae Sulzer, were studied under laboratory and greenhouse conditions. The developmental threshold temperature of the gall midge larvae was estimated to be $13^{\circ}C$. Larval and total developmental periods were 5.3 and 29 days at 25 $\pm$$2^{\circ}C$. The gall midge attacked more aphids as increasing density of peach aphids, and consumed 4 out of 10 peach aphids per day in a petri dish (9 cm in diameter) at maximum. In green house, the gall midge could control the density of the green peach aphids efficiently with a delayed density dependent-like pattern.

• Journal of Wetlands Research
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• v.20 no.2
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• pp.131-135
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• 2018

Plants produce extrafloral nectar (EFN), liquid of carbohydrates to protect themselves against various insect herbivores through attracting natural enemy, ants, wasp and parasitoids, so EFN production is well known as one of indirect defense mechanisms. In many plants, EFN production is increased or induced when plants are attacked and damaged by insect feeding, whereas there are some plants whose EFN production is not altered or even decreased upon insect attack. The feeding types (chewing or sap feeding) of insects attacking plants also affect EFN production. The objective of this study was to examine how insect herbivore alters production of extrafloral nectar of Impatiens balsamina. Two different types of herbivores, leaf chewing and sap feeding insects, Spodoptera litura and Impatientinum impatiens respectively, are utilized. Plants were mechanically damaged by making holes on leaves with Jasmonic acid (JA) and regurgitate of S. litura added on. Two different densities of aphids were confined on leaves. The results of the study was that mechanical damage and JA or regurgitate addition did not affect EFN production in I. balsamina. Aphid feeding, regardless of density treated, decreased EFN production. The results of the study suggest that production of extrafloral nectar of Impatiens balsamina can be changed by insect feeding, and the effects of insect feeding can depend on the type of insects.