Introduction
Wild plants have evolved intricate defence mechanisms
against insect herbivores [1–3] over a period of 400 million
years [4]. These depend partly on primary recognition of
the insect mediated by specific herbivore-derived molecules, termed herbivore-associated molecular patterns or
HAMPs [5,6,7]. Induced defence occurs after recognition of insect attack and includes ‘indirect defence’
entailing the emission of herbivore induced plant volatiles (HIPVs) that allow them to attract parasitoid and
predator insects that are tuned in to these signals and use
them when foraging for prey insects