Antifeedant activity of plant extracts against Spodoptera litura (Fab.) (Lepidoptera: Noctuidae).

摘要

Botanicals act not only as insecticides but also function as antifeedants, oviposition deterrents and ovicides. The present investigation reports on the antifeedant property of leaf components of Curculigo orchioides, Evolvulus alsinoides, Phyllanthus deblis, Swertia corymbosa and Zanthoxylum limonella. Solvent residues of these leaf components obtained from different solvent extracts dissolved in acetone were separately tested at 1000 ppm continuously for 24, 48 and 72 hours on the third instar larvae of the army worm, Spodoptera litura. The results indicate the presence of antifeedant effect which was maximum of Z. limonella. This was inferred from the lower food consumption ingested by the caterpillar on castor leaves containing solvent residues of these botanicals. Larval mortality was also observed when the caterpillars were fed on treated castor leaves, implying death due to either malnutrition or toxicity of these botanicals.