• Journal of Sericultural and Entomological Science
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• v.13 no.1
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• pp.17-22
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• 1971

A series of experiments were conducted from 1968 to 1970 to find the transmission effects of the dwarf disease of mulberry tree in connection with inlay grafting and insect vector with the following conclusions: 1. The inlay-grafting of sound scions on diseased roots showed a 30 per cent transmission rate among the successful grafts. The inlay-grafting of diseased scions on sound roots showed a 14 per cent transmission rate among the successful grafts ir the case of scions cut and stored before wintering but no transmission effect in the case of scions prepared after wintering, There were some stocks, among the unsuccesful grasfts of diseased scions upon sound roots, that sprouted out new buds, no transmission effects were found in them, 2. Leafhoppers (Hishimonus disciguttus Walker) collected from areas with no dwarf disease infection were grouped into three plots and let to feed on mulberry tree severely infected by dwarf disease for 7 days, 14 days and 21 days respectively. After these preliminary treatment, the leafhoppers were recollected to be fed on the sound seedling divided into three plots for 10 days, 15 days and 20 days respectively to find the transmission effects. The results are that the 7 day plot showed no transmission effect whereas the 14 day plot showed a 22 per cent disease rate and the 21 day plot 61 per cent rate indicating that the longer the feeding period is the higher the transmission rate.

• 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.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.6 no.6
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• pp.51-62
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• 1985

일반적으로 과수라 하면 사과, 배, 포도, 감, 밤 등 많은 종류가 포함되며 그들을 함께 묶어 해충관리에 대한 얘기를 하기는 어려움으로 여기서는 주로 사과, 배, 복숭아를 중심으로 많이 발생되는 주요 해충들에 대해서만 언급하기로 한다. 과수의 전 생육기간을 통하여 잎, 줄기, 뿌리, 과실 등을 가해하는 해충들을 대별하여 보면 나방류 해충으로 잎을 말고 가해하는 심식충류, 잎의 조직속으로 굴을 파고 들어가는 굴나방류, 성숙한 과실로부터 당분을 흡즙함으로서 피해를 입히는 과실 흡아류를 비롯하여 줄기속을 가해하는 유리나방, 하늘소 등의 줄기식입해충, 진딧물을 비롯한 각종의 잎 가해해충 그리고 곤충은 아니지만 일반적으로 편의상 곤충에 포함되어 취급되고 있는 응애류 등 각양각색이다. 우리나라에서는 이들 과수해충들에 대한 조사연구가 극히 미비한 상태로 주로 일본의 연구결과를 토대로 모든 방제대책을 적용하고 있는 실정이다. 특히 이들 과수해충들에 대해 연구하는 전문가가 국내에는 몇사람 되지않는 것이 심히 유감스러운 일이다. 본호에서는 이들 해충들중 여름철에 문제되는 종류들을 중심으로 그들의 개략적인 생태와 방제요령을 알아본다.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.137-139
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• 1996

The sycamore lace bug, Corythucha ciliata (Say), attacking a sycamore tree, Platatanus orientalis L., was first found in Korea, and was widely distributed in the central part of the country. The adult was milky white in color and 3.0-3.2 mm long, and the matured nymph was black. Heavily infested trees appear yellowish white as a result of feeding by the nymphs on the under surface of leaves.

• Korean journal of applied entomology
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• v.60 no.2
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• pp.241-245
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• 2021

Stomaphis (Stomaphis) matsumotoi Sorin, 1995 is reported on Juglans mandshurica Maxim. (Juglandaceae) for the first time in Korea. Photos of live aphids, illustration of slide specimens, and biometric data of apterous viviparous females are presented.

• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.56-62
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• 2000

Effects of sublethal dose of imidacloprid on biological characteristics, such as longevity, fecundity and excretions from brown planthopper (BPH) and its repellency to imidacloprid were examined. Topical application of imidacloprid to BPH at the dose of $LD_{10}$ and $LD_{30}$ (These values were determined at 48 hours after topical application of imidacloprid) was remarkably increased the mortality from 3 days after application and showed over 90% mortality on 4 days after application. Topical application of imidacloprid at dose of $LD_{10}$ (16 days) showed no difference compared to the control (16.9 days) in the longevity, while application of $LD_{30}$ was reduced the longevity of BPH to 13.5 days. Application of sublethal dose of imidacloprid to BPH adults reduced the number of eggs laid per day and for adult stage, and the hatchability of their eggs. By root zone application at the dose of $LC_{30}$, 50% longevity and 40% fecundity was reduced respectively, but showed no effect on number of eggs laid per day. The day on which BPH laid 50 % of eggs in number were 7.6 days at the $LC_{10}$ and 5.9 days the of $LC_{30}$ respectively. Hatchabilities of the groups treated with imidacloprid were lower than that of the control. Topical application to BPH at the dose of $LD_{10}$ did not reduce the amount of excretes, but application at the dose of $LD_{30}$ was reduced 26.5% of excretion compared to the control. Leaf dipping into the solution of concentration of $LC_{10}$ and $LC_{30}$ was reduced 96.4% and 98.0% of excretion, respectively. And root zone treatment at the concentration of $LC_{10}$ and $LC_{30}$ reduced 79.5% and 96.6% of excretion, respectively. Repellency rates of BPH to imidacloprid were 20% regardless of the dose of application.

• Journal of Life Science
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• v.28 no.3
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• pp.357-360
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• 2018

This study developed a method to minimize rice damages and enhance timely control by accurately classifying Whitebacked Planthopper (WBPH). The body size of the 1st-3rd instar was 1.5-2 mm, and the body size of the 4-5 instar was 2.5-3.5 mm. In the third instar, the ratio of the front wing bud and the back wing-bud was 1:1. The fourth instar occupied 3/4 of the front wing-bud, and the 5th instar showed that the front wing-bud covers the back wing-bud. It was confirmed that the 1st instar does not have a sensory plate, the 2nd instar has 2-3, the 3rd instar has 4-5, the 4th instar has 6-9, the 5th instar has 10-15, and the adult instar has 15-20 sensory plates. The female spawning organs were reddish when the spawning horn was inserted. WBPH showed that the larvae of 2-3 larvae most actively feed on rice, and the damaged area was the stem of rice near the ground. In addition, a partial black wound was observed after the feeding. WBPH-susceptible 'Chucheong' was yellowish, and early growth was slower than that of 'Cheongcheong', which was resistant; moreover, a difference between susceptibility and resistance was observed. The identification of the number of such wounds in the bioassay will be a better basis for understanding the difference in susceptibility between WBPH strains and cultivars. These results will be used as basic data for cultivating the WBPH-resistant varieties of rice.

• Korean Journal of Medicinal Crop Science
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• v.15 no.3
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• pp.199-202
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• 2007

This study was carried out to provide pest control information for the cultivation of Eleutherococcus senticosus Max. As a result of investigation of the diseases and insect pests, three pathogens and three insect pests were identified from the field sample, respectively. The identified insects pests were aphids, stinkbugs and Bothrogonia japonica. Occurrenre peaks of aphids were occurred on June and August, and generally young leaves and flower buds were injured mainly. The identified diseases were black ring spot caused by Phoma sp., gray mold caused by Botrytis cinerea and leaf blights caused by Rhizoctonia solani. The black ring spot was the most severe disease and was investigated from the beginning of June, and the incidence of the disease was 30% higher than that on September. As a result of growth test under different temperature conditions on PDA, these pathogens showed the best mycelial growth rate between 25 $^{\circ}$C and 30 $^{\circ}$C, and these results indicate that these diseases occur on hat summer season.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.335-343
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• 2003

An experiment was conducted to investigate types of injury inflicted by the stone leek leafminer, Liriomyza chinensis Kato (Diptera: Agromyzidae) on welsh onion. A feeding scar made by an adult female was a hole round in shape, with diameter of 0.08 mm and 0.48 mm in lesion, resulting in a white spot, many of which often form vertical dotted lines on a leaf. Egg spots were oval with 0.1 ${\times}$0.14 mm in size, one or several of which often form a V-shape in group. Feeding by adults began immediately after emergence and was very active from 4th to 5th day. Oviposition was done from 2nd to 6th day after emergence. In both feeding and oviposition, they were more active in the day time. Larvae after emergence crawled up the leaf at first, and then moved up and down to feed on mesophyll. When in high density, they feed on leaf from leaf tip to bottom, and let the leaf die. Area of damage per one larva was calculated as 72.1 $\textrm{mm}^2$. The aged larvae escaped from the leaf in early morning, usually between 5 and 7 am. Most pupation sites were distributed near plants,5cm in soil depth and within 10 cm away from the plant. Pupae of L. chinensis overwintered 10cm below soil surface and emerged from early May to late June the next year Adults then moved to welsh onions near over wintering sites, nursery, transplanted, and levee.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.485-491
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• 2009

This study was conducted to investigate the fruit damage according to the number of released stink bugs and date of adult introduced on non-astringent persimmon. The fruit damage differed significantly by the number, date, and the source of feed for Riptortus clavatus. Damages on the fruits appeared when five bugs were released to mother branches bearing fruits. Damages to the fruits was heavy in the case that bugs were introduced in September and October, compared with in June, July and August. Persimmon fruit damage was influenced significantly by the available sources to R. clavatus, persimmon fruit alone or additional supply of kidney bean (Phaseolus vulgaris) and water. Characteristic damage symptoms by R. clavatus showed only scars on the fruit skin, without fruit dropping. Halyomorpha halys (=mista) showed significantly higher fruit damage when they were released in July, August, and September compared with other periods. Number of H. halys to the fruit also showed significant differences in fruit damages. Five H. halys in July showed 100% damaged fruits. The fruit damage by Plautia stali was not significantly different according to dates of introduction but the number of insects gave significant differences in the fruit damage ratio at the level of 1, 3, 5 bugs introduced to the mother branche bearing friuts. The damage symptoms by P. stali was fruit dropping in July and August but from September damaged fruits were found in the branches.