Importance of flavonoids in insect--plant interactions: feeding and oviposition.

Jeffrey Harborne and colleagues have been responsible for collating the majority of data on the role of flavonoids in insect plant interactions. This article examines some of this information and assesses our knowledge about the role flavonoids play in insect feeding and oviposition behaviour. It is clear that insects can discriminate among flavonoids and that these compounds can modulate the feeding and oviposition behaviour of insects, but further work is required to understand the neural mechanisms associated with these behavioural responses. Despite the wealth of data about the diversity of flavonoids in plants, very few of these compounds have been tested against insects and their role in the evolution of host range in insect--plant interactions has yet to be determined.