Oriental fruit moth Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is an important pest for stone fruits like apple, peach, pear etc. Growers usually depend on chemical insecticides to control this pest, but it causes problems like resistance, pest resurgence, and health hazard. Although various plant extracts have been known to be potential against other lepidopterans, their effectiveness against oriental fruit moth has rarely been studied. So, we evaluated toxicity of 28 methanolic plant extracts known from previous literatures in the laboratory condition. Residual toxicity against 1st instar larvae (<5 h old) were examined using glass scintillation vial method at the concentration of 2 mg/ml. Among the tested botanicals Nicotiana tabacum L. was most effective and showed 92% mortality within 20 h and LT50 value was 12.9 h followed by Allium sativum L., Zanthoxylum piperitum (L.), and Sapindus mukorossi Gaerten. which showed 88, 70, and 65% mortality within 20 h, respectively. Rhododendron micranthum Turcz., Humulus japonicus Seibold & Zucc., Nerium indicum Mill., and other extracts showed least effectiveness on 1st instar larvae of oriental fruit moth. Hence, we suggest N. tabacum, A. sativum, Z. piperitum, and S, mukorossi as botanicals to be used against oriental fruit moth.

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