Riptortus pedestris (F.) (Hemiptera: Alydidae) is one of major pests of fruit trees and cause economic injury by piercing and sucking fruits. Although growers usually depend on synthetic insecticides to control this pest, demand for using environment-friendly insecticide is increasing. As, in our previous studies, extracts of Nicotiana tabacum L. and Allium sativum L. was effective against Grapholita molesta (Busck), we evaluated them also on the different life stages (< 24 h) of R. pedestris at 2 mg/ml in laboratory by glass scintillation vial assay. The toxicity of N. tabacum, A. sativum, and their mixture to second instar nymph was not different compared to methanol control. But, N. tabacum was more toxic to fourth instar nymph with LT50 of 59.0 h. In adult stage, the toxicity of both N. tabacum and A. sativum was higher compared to the mixture and methanol control. Thus, N. tabacum could be potential botanical insecticide against R. pedestris.

• Souvic Sarker(Department of Plant Medicals, Andong National University)
• Un Taek Lim(Department of Plant Medicals, Andong National University)