Plant resistance towards insect herbivores: a dynamic interaction

Plant defences against insect herbivores can be divided into 'static' or constitutive defences, and 'active' or induced defences, although the insecticidal compounds or proteins involved are often the same. Induced defences have aspects common to all plants, whereas the accumulation of constitutive defences is species-specific. Insect herbivores activate induced defences both locally and systemically by signalling pathways involving systemin, jasmonate, oligogalacturonic acid and hydrogen peroxide. Plants also respond to insect attack by producing volatiles, which can be used to deter herbivores, to communicate between parts of the plant, or between plants, to induce defence responses. Plant volatiles are also…