• Korean journal of applied entomology
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• v.58 no.2
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• pp.101-109
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• 2019

An entomopathogenic bacterium, Xenorhabdus ehlersii KSY, is symbiotic to a nematode, Steinernema longicaudum, and exhibits high entomopathogenic virulence against lepidopteran insects. This study showed that the bacterial pathogenicity is induced by its inhibitory activity against eicosanoid biosynthesis of target insects, resulting in immunosuppression. To be applied for insect pest control, the bacteria should be infected to insect hemocoel. To deliver X. ehlersii to inset hemocoel, Bacillus thuringiensis (Bt) was mixed with the bacteria to breakdown the physical barrier (= midgut epithelium) from midgut lumen to hemocoel. The bacterial mixture significantly enhanced insecticidal activity of Bt only against larvae of Plutella xylostella and Maruca vitrata. For formulation, X. ehlersii cells were freeze-dried and mixed with sporulated Bt cells. The formulated bacterial mixture was applied to semi-field cultivating cabbage crop infested by P. xylostella. The bacterial mixture treatment showed over 95% control efficacy, while Bt alone gave 80% control efficacy. These results suggest that X. ehlersii can be applied to develop a novel insect control agent.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.155-162
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• 2008

The Welsh onion beet armyworm, Spodoptera exigua (Hubner), has attacked Welsh onion and is now the most important pest of Welsh onion in southwestern Korea. The beet armyworm has a wide host range, occurring as a serious pest of vegetable and fields. The relatively high abundance of beet armyworm has stimulated frequent application of insecticides to foliage. Insecticide resistance is a major problem in management of this insect. Accordingly, pesticide application for the control of beet armyworm was tried in both the open field and in laboratory, using 4 synthetic compounds such as metaflumizone and chlorfenapyr, indoxacarb, flufenoxuron, emamectin benzoate. In the laboratory, each developmental stages from eggs, larva to pupa was tested against 4 insecticides. Against the eggs of welsh onion beet armyworm, there was no significantly different with each other. These tested chemicals no killing effect to eggs. However, the population of 1st larva hatched from eggs were reduced because they eaten the egg shell with residual insecticides. The tested insecticides were taken very high mortalities to 1st to 3rd larva of Welsh onion beet armyworm. Otherwise, there were decreased the death rate from 4th to 6th larva. On the other hand, their value of control effects were relatively good against Welsh onion beet armyworms in the field between 87.2 and 90.5% on 10 days after insecticide application.

• Korean journal of applied entomology
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• v.23 no.4 s.61
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• pp.233-236
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• 1984

Studies were conducted to investigate the effect of Carbofuran 3G on the density variation of rice pests and their natural enemies in case the insecticide was treated two times as compared with usual trials in paddy field. Even the two times application of Carbofuran 3G in the nursery boxes of machine transplanting and paddy water trials obtain same results to pests, small brown planthopper (Laodelphax striatllus), green rice leafhopper (Nephotettix cincticeps), brown planthorper (Nilaparvata lugens), white back planthopper (Sogotella furcifera), rice stem bore (Chilo suppressalis), rice stem maggot (Chlorops oryzae), rice thrips (cloethrips oryzae) as compared with usual trials. The density of natural enemies, spiders and egg parasite, Anagrus sp. of planthoppers in the two times application part of Carbofuran 3G increased 2.4 fold as compared with usual trials.

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.131-137
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• 2006

This experiment was conducted to select prominent microorganisms with a good insecticidal activity among the ten species, which isolated from soil at the near of Chung-buk, Chung-nam, and Gang-won provinces and made protein crystal endotoxin. As a result, GB-413 strain was finally selected, which showed the high insecticidal activity against susceptible diamondback moth (Plutella xylostella), beet army worm (Spodoptera exigua) and tobacco cutworm (Spodoptera litura) as well as resistant diamondback moth strains. By modifying the cultivation process f.g. lowing the glucose concentration at early cultivation stage and adding the carbon after inducing the spores, the percentage of making spore as well as the number of active spore were increased and the time for cultivation and spore forming was reduced without a reduction of insecticidal activity. These results were not only applied successfully for the optimized cultivation process for a fermentation tank containing five tons capacity, but also improved the possibility of mass cultivation for commercial production.

• The Korean Journal of Soil Zoology
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• v.9 no.1_2
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• pp.1-5
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• 2004

Insect pests and their natural enemies of Hibiscus Linne (Malvaceae) were investigated from March 2002 to November 2004. Fourteen insect pest species of 9 families in 5 orders were collected from Hibiscus syriacus: 5 species in Homoptera, 3 species in Lepidoptera, 2 species in Coleoptera, 1 species in Orthoprera, 1species in Hemiptera, 1 spedies in Acarina, and 1 species in Stylommatophora. Especially, Aphis gossypii Glover (Aphididae), Anomis megogona Walker(Noctuidae) and Tetranychus urticae Koch (Tetranychidae) were very important species because of their increasing daminge. The highest donsities were observed from May to June in August in Tetranychus urticae. As the enemies and ento-mopathogens of insect pests on Hibiscus syriacus, 1 species of bacteria, 3 species of fungi, 1 species of fungi, 1 species of Hemiptera, 1 species of Coleoptera, 2 species of Hymenopetera, 2 species of Diptera, and 1 species of Acarina were investigated. As the predators and parasitoids of Aphis gossypii, Aphidoletes aphidoletes aphidimyza Rondani (Cecidomyiidae), Meliscaeva cinctella Zetterstedt (Syrphidae), Harmonia axyridis Pallas (Coccinellidae), and Aphidius gifuensis Ashmead (Braconidae), entomopathogenic fungi, Vericillium lecani naturalis strain (Moniliaceae) and Beauveria bassiana naturalis strain strain (Hypocreaceae) were observed and Bacillus thuringiensis naturalis strain (Bacillaceae), B. bassiana, Metarhizium anisopliae naturalis strain (Hypocreaceae), predators of Tetranychus urticae, Amblyseius sp. (Phytoseiidae), and Orius sp. (Anthocoridae) were observed.

• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.526-539
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• 2011

The purpose of this study is to identify insects inhabiting Mulyeongari-Oreum wetland and to provide basic information for conservation of wetlands. As a result, a total 229 species, 73 families, 9 orders of insects were collected: 136 species, 39 families, 6 orders from Mulyeongari-Oreum Wetland and 121 species, 52 families, 9 orders from Mt. Sooryeong. Of the 229 species of insects investigated, Copris tripartitus Waterhouse, an endangered species of wildlife fauna in Korea, was found with many individuals. Also, Lychnuris rufa(Olivier), having a narrow habitat near unpolluted water and mountains, was also recorded with 3 individuals and then should be considered as a protected species in Wetlands. To identify the community structure of moth on Mulyeongari-Oreum wetland, a light trap was examined and a total 76 species of moths were collected. Total dominant species was Hydrillodes morosa(Butler) with index of 0.12 and the species diversity on the moth community from survey area was the highest in July with index of 3.42.

• Landscaping Tree
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• s.85
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• pp.9-11
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• 2005

봄이면 항상 아지랑이 속에 나울나울 봄바람과 함께 분홍빛 자태를 들어내며 겨우내 추웠던 흔적을 지우고 세상사 으뜸은 ''나pos; 라고 소리치는 진달래! 우리의 동산을 채우고, 우리집 마당을 채우고, 길가의 언덕까지 채우고, 내 마음의 허전함을 채우는 철쭉, 진달래 등 종류도 다양하고 품종도 다양하다. 정원수와 조경수로 많이 선호하며 몇몇 지방에서는 5월이면 철쭉 축제도 개최하는 곳이 있다. 하지만 이 아름다운 나무를 못 살게 구는 몇몇 병해충이 있으니 진달래방패벌레, 독나방, 극동등애잎벌, 철쭉떡병 등이 대표적인 병해충이다. 이들에 대한 피해현상과 방제법에 대하여 간단히 소개하고자 한다.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.364-375
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• 2014

This study was carried out to investigate the pesticide efficacy and crop safety among different leafy vegetables applied with foliar spraying under greenhouse and to check extrapolating from some trial data to other minor crops. Leafy vegetables used in this study were: lettuce (Lactuca sativar), leaf broccoli (Brassica oleracea.), chicory (Cichorium intybus.), chinese cabbage (Brassica campestris subsp. napus var. pekinensis), radish (Raphanus sativus), rape (Brassica napus), crown daisy (Chrysanthemum coronarium), edible burdock (Arctium lappa), endive (Cichorium endivia) and mustard greens (Brassica jumcea). Based on the result of control efficacy, all crops were classified into the groups. The results showed the probabilities of extrapolating the control value data of minor crop within the same group. It would be possible to use the pesticides which are already been registered for similar crops to those crops have no registered pesticides.

• Korean journal of applied entomology
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• v.36 no.3
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• pp.256-263
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• 1997

Supercooling points (SCP) and cold tolerance of the tobacco cutworm, Spodol~rera litura Fabricius. were measured in response to subzero temperatures. SCPs were varied among developmental stages. Eggs showed the lowest SCP (-27$^{\circ}$C). Pupae and adults had the intermediate SCP(- 18$^{\circ}$C). The SCPs (- I0 to - 16$^{\circ}$C) of larvae increased with their ages. Lethal low temperature of each stage was higher than its SCP. Preexposure of eggs and larvae to a sublethal low temperature increased their survival capacities under lethal low temperatures. The sublethal temperature also induced the fifth instar larvae to increase hemolymph osmolality and to produce cold-induced proteins of apparent molecular weights of 20 and 27 kD. These results indicate that this species is classified into a freeze-susceptible insect.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.109-115
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• 1999

Morphological characteristics and life cycle of Udea ferrugalis (Hubner) attacking Angelica utilis were studied in 1995 and 1996. Egg of U. ferrugalis was oval-shaped with light-gray. Larva was milk white or light yellow color with 1.50-14.6 mm body length, depending on their developmental stages from 1st to 5th instar. Pupa were deep-brown with 8.2-9.7 mm length. Adults were brown color and body lengths were 10.1 mm and 8.3 mm and wing expanse lengths were 18.5 mm and 16.6mm with female and male, respectively. At 20$^{\circ}$C, each developmently periods was 5.81, 19.0, 3.46 and 1 l.0days with egg, larvae, pre-pupae, and pupae, respectively. Also adult longevitys were 10.13 for female and 9.8 days for male. Average number of egg were 238.5 and 248.8 at 20$^{\circ}$C and 30$^{\circ}$C, respectively. A total of 12 species host plants were identified in the outdoor observation in Chungbuk province.