Insecticidal activities of tea saponin against diamondback moth, Plutella xylostella and aphid, Aphis craccivora

Insecticidal activities of tea saponin were evaluated against larvae of diamondback moth, Plutella xylostella (L.) and aphid, Aphis craccivora Koch. In residual toxicity assay, saponin was found more effective against second instar larvae of P. xylostella (LC50=2106.32 mg L1) and A. craccivora (LC50 = 540.79 mg L−1) after 96 h as compared to positive control. In repellent activity study, saponin at 4000 mg L−1 showed higher repellence (48.57%) to third instar larvae of P. xylostella. However, feeding preference index (PI) of saponin was less in higher concentration (0.63) against third instar larvae of P. xylostella.