• Korean journal of applied entomology
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• v.42 no.4
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• pp.329-334
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• 2003

To study the interaction between rice weevil and storage molds, the preference of rice weevil to the four mold species (Aspergilus candidus, A. niger, A. flavus and Penicillium spp.) and the resulting reproduction of the rice weevil were observed. The rice weevil preferred rice grains contaminated with the molds to autoclaved ones regardless of the mold species tested. Among the four mold species, A. candidus and Penicillium sp. were highly preferred than the others. Reproduction of the rice weevil was higher on the grains contalminated with A. candidus and Penicillium sp., than on autoclaved ones, but was lower on the grains contaminated with A. flavus. The partial disagreement between preference and reproduction of the rice weevil might be a suggestion that both the weevil behavior adapting nutritional requirements and the process of the long intensive coadaptation of the rice weevil and storage molds requiring similar moisture niche are the major components of the population interaction between the weevil and molds.

• Korean journal of applied entomology
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• v.27 no.1
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• pp.14-20
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• 1988

쌀바구미 생명표 통계량을 정온 조건과 실온 조건에서 산출하였다. 온일도를 단위로 하였을 때 $20^{\circ}$~ $30^{\circ}$ 범위내 정온 조건에서의 통계량은 실온 조건에서의 통계량과 유사한 차이를 보이지 않았으며 온도간의 변이는 실온에서의 간 변이와 유사하였다. 이 결과는 온일도를 시간단위로 할 때 쌀바구미의 생화사가 표준화 될 수 있음을 시사하는 것이었다. 쌀바구미는 $368pm$41.2DD에서 산란을 시작하여 $1391.0\pm$38.7DD에서 멈추는 것으로 추정되었다. 외적 자연회가졸 밀도 음가 기간과 평균세대 기간은 각각$ 0.0052\pm$0.0006/DD, $134.7\pm$15.0 DD 그리고 $715.2\pm$53.6 DD인 것으로 산출되었다.

• Journal of Applied Biological Chemistry
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• v.61 no.3
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• pp.239-243
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• 2018

Essential oils of coriander (Coriandrum sativum L.) seeds were extracted by three extraction methods, steam distillation extraction (SDE), hexane extraction (HE) and supercritical extraction (SE), to compare their insecticidal activities against Sitophilus oryzae and S. zeamais. Although the essential oil extracted by HE and SE did not show insecticidal activities, the essential oil extracted by SDE showed the highest insecticidal activities against S. oryzae and S. zeamais. The chemical compositions of the essential oil extracted by SDE were analyzed by GC-MS. The most abundant compounds were linalool (59.92%), camphor (7.94%), linalool oxide (7.70%), p-cymene (7.44%), ${\alpha}-pinene$ (6.44%), limonene (3.29%) and geranyl acetate (3.19%). Camphor and linalool as major constituents showed the highest insecticidal activities against S. oryzae and S. zeamais whereas other constituents did not show insecticidal activities. As a result, the essential oil extracted by SDE, camphor and linalool showed a potential for development as insecticide against the storage pests.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.257-260
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• 1982

During the rice storage at $28^{\cir}{\pm}1^{\cir}C$ and $60{\sim}70%$ R.H., the moisture content of rice, was increased max. 1. 6% by the activity of rice weevil. The growth of Asp. repens was not affected, while Asp. niger was inhibited after the appearance of its second generation adults. The development of rice weevil was generally accelerated by both of Asp. repens and Asp. niger, but decelerated at higher density of Asp. niger($1.6{\times}10^4$ propagules/g). The total number of rice weevil showed no significant difference during six weeks.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.344-349
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• 1995

To isolate naturally occurring novel Bacillus thuringiensis strains for useful pest con시 agents, A total of 64 isolates of B. thuringiensis producing spore and crystal were obtained from 583 soil samples in Korea. Toxicity of isolates was assayed against Lepidoptera (Bombyx ori), Diptera (Culex pipens) and Coleoptera (Sitophilus oryzae), respectively. The results showed that B. thuringiensis isolates toxic Lepidoptera are 42.2% , both Lepidoptera and Diptera are 31.3% and Diptera are 20.3%, demonstrating that spectrum of insecticidal activity of B. thuringiensis isolates is various. But no B. thuringiensis isolates have toxicity against Coleoptera.

• Korean journal of applied entomology
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• v.36 no.3
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• pp.215-223
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• 1997

A matrix model of rice weevil population based on degree day (DD) was constructed. The basic matrix model predicted on exponential jncrcase of the adult weevil density and the finite rate of increase(h) of the population was estimated to be 2.155/100DD. Adult density simulated by the matrix model including intraspecific competition showed a damped oscillation over time and reached at the stationary level of 530 at 69, 300DD. The experimental population showed similar features to that of the model. But there were some differences in the highest density and period of adult oscillation. The differences could largely be caused by the assumption of the model; resource constancy.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1997.04a
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• pp.19-19
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• 1997

• Korean journal of applied entomology
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• v.28 no.1
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• pp.28-31
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• 1989

Lariophagus distinguendus,an ectoparasitoid of rice weevil, laid its eggs exclusively on the third and fourth larvae, with the preference for the fourth larva. The sex ratio of the pa¬rasitoid can be regulated by the female parasitoid on the basis of the host size available at the time of oviposition.

• Applied Biological Chemistry
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• v.32 no.3
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• pp.265-269
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• 1989

Effects of air-tighteness of packing material and aluminum phosphide fumigation on mortality of rice weevil were studied during rice storage. Air-tight storage of rice in sealed bag of 0.1mm PE film or sealed glass bottle reduced the deterioration of rice quality and killed all rice weevils after 60 days storage, while paper bag, PP bag and straw bag storage kept them alive. One tablet of aluminum phosphide in one cubic meter heap of rice packed in PP bag was sufficient to kill all rice weevil in it, when the heap was covered by 0.15 mm PE film during fumigation.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2001.05a
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• pp.132-132
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• 2001