The influence of host and non-host companion plants on the behaviour of pest insects in field crops

摘要: Companion plants grown as ‘trap crops’ or ‘intercrops’ can be used to reduce insect infestations in field crops. The ways which such reductions are achieved being described currently using either a chemical approach, based on the ‘push-pull strategy’, biological ‘appropriate/inappropriate landing theory’. approach suggests that numbers reduced by chemicals from intercrop ‘repelling’ insects main crop, and trap-crop ‘attracting’ away crop. This is assumptions (1) release detectable amounts of volatile chemicals, (2) ‘respond’ while still some distance emitting plant. We discuss whether above justified Our tenet specialist respond only released their host these small quantities that, even with heightened response detect them when few metres find no robust evidence literature plant ‘attract’ more than 5 m believe function simply ‘interception barriers’. also ‘repelled’ non-host plants. Instead, we disrupt host-plant finding providing choice (appropriate) (inappropriate) leaves land, our research has shown for intercropping effective, must land Work needed determine repellent (chemical approach) ‘non-stimulating’ (biological insects.