International Journal of Farm Sciences

The aqueous extract of eight plant species, namely Azadirachta indica, A Juss, Melia azedarach L, Lantana camara L Moldenke, Cannabis sativa L, Nerium indicum Mill, Eucalyptus sp, Ricinus communis L and Solanum nigrum L were tested for repellent effects against Pieris brassicae. The ethanol extracts of potential plants were further tested for their biological activity against the test insect. The aqueous extracts of A indica and M azedarach resulted in statistically higher repellent effect repelling 2.2–50.4 and 4.4–52.6 per cent second instar larvae of P brassicae respectively. In case of ethanol extract also seed extracts of A indica and M azedarach were highly effective against P brassicae giving statistically higher repellent (15.1% and 13% respectively) effects as compared to other plant extracts. In general repellent effect was dose dependent and diminished with the passage of time.