Feeding deterrents for the grass grub Costelytra zealandica(Coleoptera: Scarabaeidae) in the root of a resistant pasture plant, Lotus pedunculatus

The addition of a crude extract of Lotus pedunculatus root to a medium containing a strong feeding stimulant for 3rd-instar Costelytra zealandica larvae reduced ingestion to a negligible level. Two, possibly three feeding deterrents have been isolated from the active extract, and have been partially characterised.