Early herbivory-induced responses in plants
In this thesis I analysed herbivore perception and herbivory-induced signalling in two plants species, the solanaceous plant N. attenuata and the brassicacean plant A. thaliana. Herbivore detection can be divided into perception of molecular events inflicted by tissue damage, classified as damage-associated molecular patterns (DAMPs) and detection of herbivore-derived elicitors, classified as herbivore-associated molecular patters (HAMPs). The first manuscript deals with the role two protein kinases in N. attenuata, SIPK and WIPK, which were previously shown to be quickly activated by DAMPs and HAMPs. Silencing both kinases highly diminished the accumulation of phytohormones and defense metabolites in N. attenuata, however, these kinase-silenced plants were not particularly susceptible to native herbivores when transplanted into the plants natural environment. This surprising effect could be explained by reduced emissions of green leaf volatiles (GLVs) from attacked SIPK and WIPK silenced plants. Another new finding presented in this thesis is the importance of SGT1 in plant perception of herbivory. SGT1 regulates jasmonate (JA) biosynthesis in N. attenuata and resistance to the specialist herbivore Manduca sexta. A mini-review summarizes current knowledge about the role of SGT1 in plant defense and development.