title: Chemical stimulants and deterrents regulating acceptance or rejection of crucifers by cabbage butterflies.
abstract: GravidPieris rapae butterflies oviposit on many, but not all, crucifers. Rejection ofErysimum cheiranthoides andCapsella bursa-pastoris was initially explained by the presence of chemical deterrents in the plants. Analyses and bioassays of plant extracts indicated the absence of oviposition stimulants inC. bursa-pastoris, but similar chemical separation ofE. cheiranthoides extracts revealed the presence of stimulants as well as deterrents. Choice tests illustrate how acceptance or rejection of a plant by an insect may depend on the balance of positive and negative chemical stimuli within the plant.
authors.affiliation: Boyce Thompson Institute, 14853, Ithaca, New York.
authors.forename: J A
authors.initials: JA
authors.lastname: Renwick
authors.forename: C D
authors.initials: CD
authors.lastname: Radke