• 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.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.23-29
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• 2008

The biology of indian meal moth and maize weevil on the trehalose gene introduced rice (var 'Nakdong') (T-Nakdong) was compared to that on the rice without gene introduction (Nakdong) at $28{\pm}1.0^{\circ}C$. Development of the both two insects was significantly delayed; on T-Nakdong, the developmental periods of female moth $({\pm}SE)$ and weevil were $38.46{\pm}0.42\;and\;36.38{\pm}0.28days$, respectively. Whereas those on Nakdong were $36.38{\pm}0.28\;and\;34.33{\pm}0.18$, respectively. Net reproduction rate of Indian meal moth on T-Nakdong $(3.0{\pm}0.14)$ was significantly lower than that on Nakdong $(9.25{\pm}0.13)$, due to the lower emergence rate $(21.08{\pm}0.04%\;vs\;48.30{\pm}0.06%)$. The life table statistics of maize weevil on T-Nakdong was estimated to be similar to those on Nakdong. The delayed development of T-Nakdong suggested that the factor for development of the insects could be changed by the introduction of trehalose gene into the rice variety.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.310-316
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• 2011

This study was performed to evaluate the contact toxicity and residual toxicity of the 26 commercially registered insecticides against cigarette beetle, Lasioderma serricorne and maize weevil, Sitophilus zeamais adult. Among 26 insecticides, seven insecticides (chlorpyrifos, chlorpyrifos-methyl, fenitrothion, fenthion, phenthoate, cypermethrin, ${\alpha}$-cyhalothrin) against L. serricorne adult and five insecticides (chlorpyrifos, chlorpyrifos-methyl, fenitrothion, fenthion, phenthoate) against S. zeamais adult showed perfect mortality, $LC_{50}$ (ppm) values of those selected insecticides were appeared lowest value on ${\alpha}$-cyhalothrin (1.46) against L. serricorne adult and chlorpyrifos-methyl (0.64) against S, zeamais adult, respectively. However, chlorpyrifos-methyl still remain high toxicity until 90th days after treatment against both L. serricorne and S. zeamais adults. From above results, it will be useful information to select insecticides effective against L. serricorne and S. zeamais adults.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.110-116
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• 1991

As the model compounds, citral and n-octanol which possess similar characteristics and structures of low molecular weight insect pheromones and $({\pm})-5-hydroxy-4-methyl-heptan-3-one$ which shows the aggregation pheromones activity of the rice weevil and the maize weevil were microencapsulated with low molecular weight polyethylene(LMPE) and urea-formaldehyde resin as wall materials. The core materials were microencapsulated as small particles in LMPE and urea-formaldehyde resin polymers and the microencapsulated polymers were white powders. And the polymer made from urea-formaldehyde resin was better than that from LMPE as wall material. The slow releasing effect and the releasing patten of the microencapsulated core materials were examined by solvent extraction method and headspace sampling method. Citral and n-octanol and $({\pm})-5-hydroxy-4-methyl-heptan-3-one$ were release more than 40 days and 15 days, respectively. The releasing pattern of urea-formaldehyde resin microcapsules showed rather smooth decrease than that of LMPE and was maintained at steady level longer.