• Korean journal of applied entomology
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• v.30 no.4
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• pp.291-293
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• 1991

Inter-regional difference in median lethal concentration of Bacillus thuringiensis diamondback moth was disclosed to be high. Pyungchang strain showed at most 41 times resistance compared to KN-IA strain of which $LC_{50}$ value was 5.5 ppm. and Oksan strain Showed 11 times resistance. The JMC strain, susceptible to pyrethroids, also showed 12 times resistance against B.T., suggesting difference in resistance mechanism between pyrethroid and B.t.

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.63-71
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• 1979

Tests were made to find new non-mercurious seed disinfectants that were best for rice seeds. For these experiments four seed samples carr)?ing natural infection of Pyricularia oryzae, Helminthosporium oryzae, and Fusarium moniliforme were used and the following fungicides were used; Zinc Omadine, Sodium Omadine, Panoctine, Tecto-F, Benlate-T, Homai, Sisthane, $P_{242}$, Busan 30, Tecto-Wp and Terracoat Zn. Blotter method and water agar plate method used in the laboratory and growing-on test used in greenhouse. Results have shown that Sisthane, $P_{242}$ and Sodium Omadine have equal or superior effect to organic mercury compound against P. oryzae, H. oryzae, and F. moniliforme. Benlate T and Homai are effective against blast and Bakanae disease, but are inferior to organic mercury compound against brown spot disease. Busan 30 and Panoctine are effective against blast and brown spot disease, but have moderately inferior effects against F. monilifome. It is considered that the recommendable testing methods of seed treatment were blotter method for P. oryzae and water agar plate method for H, oryzae and F. moniliforme according to the experimental results obtained. No phytotoxicity against seed germination and seedling growth were observed when treated with disinfectants before germination of seeds.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.45-51
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• 2009

This paper presents sequential sampling plans for evaluating the pest density based on complete counts from probe in a rice storage warehouse. Both maize weevil and Indian meal moth population showed negative binomial dispersion patterns in brown rice storage. For cost-effective monitoring and action decision making system, sequential sampling plans by using the sequential probability ratio test (SPRT) were developed for the maize weevil and Indian meal moth in warehouses with 0.8 M/T storage bags. The action threshold for the two insect pests was estimated to 5 insects per kg, which was projected by a matrix model. The results show that, using SPRT methods, managers can make decisions using only 20 probe with a minimum risk of incorrect assessment.

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.33-39
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• 1965

Author investigated the control measure and the life cycle of the mulberry sucker, Anemoneura mori Schwarz. The results are as follows; 1. It is clear that the life cycle of mulberry sucker is one generation a year, but not obvious about the duration of pupa. 2. Even though various insecticides were used for control, they are not of a practical value during the egg stage. It is, however, believed that the mulberry sucker, when become larvae, can be controlled by spraying about 400 litres per 1 tanbo( DDVP, 1000$\times$). 3. Author recommends the control measures which you may use not only an insecticide, but also cut off branches so as to make leaf get enough sunlight and ventilation.

• Journal of Sericultural and Entomological Science
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• v.19 no.1
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• pp.25-32
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• 1977

The flacherie (FV) and Ina-flacherie (Ina-FV, named arbitarily) viruses of the silkworm, Bombyx mori was isolated from infectious larvae. Two types of infectious particles were purified by sucrose density gradient centrifugation. Some properties of the purified particles were investigated. Electron micrographs showed that FV and Ina-FV were spherical particles with diameters of 27nm and 20nm, respectively. The sedimentation coefficient of Ina-FV was 80S.

• Journal of Sericultural and Entomological Science
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• v.1
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• pp.9-14
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• 1960

접목법은 우리나라에 있어서의 유일한 상묘생산의 수단인데도 불구하고 해년 그 성적이 좋지 못하여 그 생산에 지대한 지장을 주고 있는 실정에 비추어 필자는 이의 성묘비율을 향상시킬 수 있는 몇 가지 방도에 대하여 이미 실험을 행한 결과 접목후의 가식일수, 이식심도, 묘포의 피복물, 종목채취시기, 시비량등이 접목의 활착이나 묘목의 생육에 영향이 있음을 보고한바 있거니와 필자는 그후 이접하여 국내 주요 상품종에 대하여 품종상호간에 있어서 활착비율에 어떠한 정도의 차이가 있는가 또는 품종의 차이에 따라서 접목적기에 차이가 있는지의 여부와 아울러서 중부지방에 있어서의 접목의 적기를 조사하고 또 한편 우리나라에서 현재 행하고 있는 주요한 각종접목법에 대하여 그 상호간에 있어서의 활착비율의 차이와 묘목의 생육상태 및 접목법의 차이에 따르는 접목적기등을 알기 위하여 4286년부터 5개년간에 걸쳐서 시험을 계속한 결과 그 성적을 얻었으므로 여기에 그 개요를 보고하려고 하는 것이다. (중략)

• Korean journal of applied entomology
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• v.33 no.4
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• pp.207-215
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• 1994

The brown planthopper (BPH), Nilaparuata lugens, is the major pest 01 nce in Asla. Cument control tactics rely pnmalily on chemical ~nsecticides and resistant nce varieties In Korea, the most important biolog~cal conb-ol agent appears to be the naturally-occuning, mermlthid nematode, Agarnermrs unka. Although parasitism of BPH is highly variable from place to place and from year to year. the rnermithid is a promising biological control agent because it reduces the fecundity of the host and ultimately causes its death. The memithid has only one generation per year compared to the three to four generations of BPH, but the mermithid lemales stagger their egg production so that many individuals in all BPH generations are parastized. Augmentation of this rnermithld into BPH populations is only psslble on a limited scale because it is an obligate parasite and mass production technology has yet to be developed. Conservation of naturally-occumng populations through cultural techniques and the use of compatible resistant rice varieties and chemical insecticides may lead to an effective integrated pest management program for BPH.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.153-158
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• 2007

This study was conducted to develope the observing methods for density of stink bugs in soybean reproductive stage. The adults and nymphs of bean bug, Riptortus clavatus, red-banded shield bug, Piezodous hybneri, green stink bug, Nezara antennata, Sole bug, Dolycoris baccarum, and brown marmorated stink bug, Halyomorpha halys were observed by three observing methods such as beating, sweeping net, and visual counting methods in the full bloom (R2), full pod (R4) and beginning maturity (R7) of soybean. As a result, total number of stink bugs observed was the highest with 5,214.2 by beating method, and then was 2,581.8 by visual counting method, and was the lowest with 103.1 by sweeping net method. Total number of stink bugs observed by the beating and visual counting methods was P. hybneri, followed by N. antennata, H. halys, R. clavatus and D. baccarum with clear difference in observed number of each stink bugs while total number of stink bugs observed by sweeping net method was very low in the range of 18 to 23. Accordingly, the observed density of stink bugs exception of R. clavatus adult by beating method was generally high. However, the number of R. clavatus adult was more observed by flushing method than that by beating method from the beginning bloom (R1) to full maturity (R8), and was more observed at morning time than that at afternoon time. Therefore, two observation methods that flushing method for R. clavatus and beating method for the other stink bugs were recommended for the occurring density of stink bugs in soybean because both bean bug and pentatomidae stink bugs have distinct behavior characteristics such as flying and dropping.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.105-109
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• 2001

Dispersion pattern of the citrus red mite (CRM), Panonychus citri (McGregor) was determined to develop a monitoring method in the satsuma mandarin fields, Citrus unshiu L., in Jeju-do, during 1999 and 2000. CRM population was sampled by collecting leaves. Taylor's power law provided better description of mean-variance relationship for the dispersion indices compared to Iwao's patchiness regression. Slopes and intercepts of Taylor's power law from leaf samples did not differ among surveyed groves. Fixed-precision levels (D) of a sequential sampling plan were developed using Taylor's power law parameters generated from all motile stages of CRM in leaf sample. This sampling plan for leaf sample estimate was tested with resampling validation for sampling plan using 4 independent data sets. Resampling simulation analysis demonstrated that actual fixed-precision level values were better than desired D values of 0.20, 0.25 and 0.30. Required numbers for tree sampling at the density of more than 7 mites per tree were fewer than 18.

• Korean journal of applied entomology
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• v.55 no.3
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• pp.267-275
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• 2016

Chlorine dioxide has an insecticidal activity via its production of reactive oxygen species (ROS). Its cytotoxic activity has been regarded as a main cause of the insecticidal activity. This study tested a hypothesis that cytotoxicity of chlorine dioxide is resulted from its induction of apoptosis against target cells using ROS. Injection of chlorine dioxide significantly reduced total hemocyte counts of Plodia interpunctella larvae and subsequently killed the larvae. To analyze the cytotoxicity with respect to apoptosis, terminal deoxyribonucleotidyl transferase nick end translation (TUNEL) assay was performed. An insect cell line (Sf9) cells were exposed to different concentrations of chlorine dioxide. TUNEL assay showed that chlorine dioxide induced significant apoptosis of Sf9 cells in a dose-dependent manner. When different concentrations of chlorine dioxide were injected to larvae of P. interpunctella, it showed a dose-dependent induction of apoptosis against hemocytes. However, addition of vitamin E significantly suppressed the apoptosis induction and insecticidal activity of chlorine dioxide in a dose-dependent manner. These results suggest that cytotoxicity of chlorine dioxide is resulted from its induction of apoptosis against insect cells using ROS.