Plant Volatiles and Their Role in Insect Olfaction

Plant volatiles are the invisible players in the plant-insect co-evolutionary arms race. They are involved in various plant-mediated tri-trophic interactions within the ecosystem. Volatiles, emitted from different parts of the plant, serves as a cue for the host-seeking herbivores. Interestingly, insects perceive and process such complex environmental cues with their advanced olfactory system. During herbivory, plants also produce defensive volatiles recognized as herbivore-induced plant volatiles (HIPVs) that often serve a dual purpose by attracting the natural enemies and giving an alarming signal to the plants nearby. Insects tend to avoid the host plants emitting such defensive volatiles and non-host plants, releasing non-host volatiles (NHVs). Understanding the dynamics of host selection through plant volatile recognition by pest insects is highly important to develop eco-friendly pest management practices employing strategies such as push-pull strategy. In the present chapter, we have reviewed different aspects of plant volatile production, insect olfactory system organization, the contribution of plant volatiles in host-seeking behavior of insects, and finally their potential use in formulating insect pest management strategies.