Anti-feedant, repellent and growth regulatory effects of four plant extracts on Pieris brassicae larvae (Lepidoptera: Pieridae)

Amongst the four aqueous extracts of four locally available plants namely, Artemisia vulgaris, Datura arborea, Nicotiana tabacum and Zanthorylum alatum, the Z. alatum was the most potent as a feeding deterrent and repellent, and also caused the highest mortality of Pieris brassicae larvae. Datura arborea was seen to exhibit Insect growth regulatory (IGr) activity by causing late pupation of the larvae. All extracts exhibited significant differences (P ≤ 0.005) in feeding deterrence, repellent action, mortality, and late pupation when compared with the non-treated controls.