This study was carried out to evaluate toxicities of two formulations (microemulsion, ME and wettable powder, WP) for acetamiprid+etofenprox against aphids (Aphis gossypii), thrips (Frankliniella occidentalis) on the cucumber greenhouse and whiteflies (Trialeurodes vaporariorum and Bemisia tabaci Qbiotype) on the tomato greenhouse. The activities of two formulations were evaluated by testing residual effect and toxicities against eggs, nymphs and adults of whiteflies in the laboratory, and control effect in the greenhouse against whiteflies, aphids and thrips. All trials were tested at the recommended concentration(RC) and a half concentration of RC of each formulation. In the laboratory trials against eggs and nymphs of whiteflies, the effect of ME was more effective than that of WP and showed more than 80% ovicidal activities, and 40%~60% larvicidal activities on the 3rd instars nymph of whiteflies at the recommended and its half concentrations. On the residual effect against the adults of the two whitefly species, WP formulation was more effective than ME and showed more than 70% mortality at the 5th day after treatments of recommended concentrations. In the field trials, the effects of ME against whiteflies and thrips were more excellent than those of WP. On the other hand, the effect of WP against aphids was more excellent. These results indicate that the formulation of insecticide can be played an important role in the control strategy of the pest in field.

This study was conducted to improve the effect of environment-friendly Tetranychus urticae pesticide through the development of Tetranychus urticae biopesticide using the plant extract. Tested extracts were fig leaf extract, viburnum erosum extract; besides Sophora flavescens Ait extract, Derris root extract, Tobacco leaf extract, and they were proved to be the caricidal effect of two spotted spider mite adults by spraying on the French bean leaf inoculated for Tetranychus urticae with each concentration; 500ppm, 200ppm, 100ppm, 50ppm. In the control treatments, caricidal effect was compared with only ‘Eungsami’ (500ppm, 200ppm, 100ppm, 50ppm), of which the main ingredient as environment-friendly organic material is, and distilled water. The caricidal effect of tested extracts to the two spotted spider mite adult was the highest in the Sophora flavescens Ait extract and Tobacco leaf extract over 90%, and comparatively low in the Derris root extract. When the caricidal effect of ‘Eungsami’ was compared with two spotted spider mite adults with each concentration, ‘Eungsami’(500ppm) and Tobacco leaf extract(500ppm) were very excellent as each 95.5%, 98.7% in treated concentration. The effect of Sophora flavescens Ait extract was also high as 96.5%. In the low concentration(50ppm), Sophora flavescens Ait extract was 45.8%, Tobacco leaf extract was the most effective as 53.8%.

Six kinds of insecticides, fenpropathrin, dicofol, milbemectin, tebufenpyrad, monocrotophos and propargite, were selected for investigating LC50s to local two spotted spider mite(TSSM) strains. The TSSMs were collected from peach (Cheongdo area) and apple orchards (Chungju, Kunwi and Sobo areas) in 2005, from strawberry plastic house (Nonsan and Damyang areas) in 2006 for experiment and some insecticides selected TSSM strains for more than 20 generations were also used. Each strain was clustered by LC50 value got from six selected insecticides treatment. Every insecticide showed about three-fourfold LC50 difference among TSSMs caught in same area. There are no specific differences in LC50 patterns of TSSM to insecticides within peach orchard and among apple orchards. But TSSMs of apple orchard and peach orchard were clustered into different group each other. Grouping of selected TSSM strains with insecticides in lab artificially showed good relationship between action mechanisms of insecticides. In strawberry strains TSSM showed regional differences between Damyan and Nonsan. The TSSMs of Nonsan showed more resistance to Tebyfenpyrad and Propargite, but TSSM of Damyang was more resistant to fenpropathrin than that of Nonsan. The TSSMs selected with monocrotophos and bifenazate, known as acetylcholinesterase inhibitors, and also pyridaben and chlorfenapyr, known as inhibitors of mitochondrial electron transportation, were grouped close respectively.

Deraeocoris brevis Knight (Hemiptera: Miridae) is a generalist predator and is a key natural enemy in pear orchards in the northwestern United States. Although D. brevis undoubtedly contributes to the regulation of major pear pests, pesticides often disrupt its activity and reduce its effectiveness as a biological control agent. A temperature-dependent stage-structured matrix model was developed to analyse the population dynamics of D. brevis influenced by insecticides. In this study, impacts of acetamiprid on field populations of D. brevis were analysed. The age class of D. brevis was categorized into four stages: eggs, small nymphs (1st to 3rd instar), large nymphs (4th to 5th instar), and adults. Probabilities for each element in the projection matrix were estimated using published temperature-dependent developmental data of D. brevis. Transition probabilities from an age class to the next age class or the probabilities of remaining in the age class were obtained from development rate function of each stage (age classes). The fecundity coefficients of adult population were the products of adult longevity completion rate (1/longevity) and temperature-dependent total fecundity. Also, direct and indirect residual effects of acetamiprid were incorporated into the model. The model results were much overestimated compared with observed actual data from 25d after model running. Such a discrepancy might be occurred from various reasons such as an intra-species competition, successful fecundity rate, etc. Further, the improvement and application of the model were discussed.

탈피호르몬의 작용을 방해하는 농약제인 tebufenozide 를 알에서 부화한 지 7일째의 C. riparius에 처리하여 성충이 될 때까지의 생장과정을 연구하였다. C. riparius 에 control, 10 μg L-1, 30 μg L-1, 60 μg L-1와 100 μg L-1의 농도로 약제를 처리하였다. 전체적으로 약제를 처리한 하루 후인 D12에 16%가 치사

밀양에서 채집한 담배거세미나방 유충의 약제감수성을 조사하였다. 약제의 반수치 사농도는 1령층에서 0.5-5.6ppm,2령층에서 9.9-27.9ppm, 3령층에서 9.6-125.1ppm 및 4령층에서 24.3-546.6ppm으로 약종에 따른 차이와 함께 유충의 영기가 증가할수록 높았다. 또한 약제별 추천농도에 대한 유충의 90%치사농도의 비로 나타낸 약제내성비(내성비= 약제별 추천농도)도 1령충에서 0.04-0.8, 2령충에서 0.2-7.5, 3령충에서 0.7-115.3및 4령충 에서 1.2-483.4으로 약종에 따른 차이와 함께 유충의 영기가 증가할수록 높았다. 한편,동일 약제에서 유충의 영기간 반수치사농도, 및 내성비의 차이는 chlorfenapyr, chlorpyrifos 및 EPN에서 매우 낮았으며, lufenuron, chlorfluazuron및 teflubenzuron에서 매우 높았다. 이러한 결과를 종합하면 담배거세미나방 유충의 방제는 영기가 어릴수록 또한 약제감수성이 낮은 약제, 즉 반수치사농도 및 내성비의 차이가 적은 약제인 chlorfenapyr, chlorpyrifos 및 EPN을 사용할수록 효과적임을 의미한다.