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%.