Interactions between herbivores, pathogens and plants

The aim of my thesis is to fill important knowledge gaps in our understanding of the impact of important consumer groups, invertebrate herbivores and fungal pathogens, on plant communities and associated microbial organisms. The interacting effects of consumers and mutualists have rarely been assessed and therefore this work will address these interctions. I will explore the mechanisms by which consumers interact to affect plant communities, and whether plant defence mechanisms against different consumer groups are related to each other, or instead trade off with each other (e.g., Felton & Korth 2000). Finally, I will investigate the interactions between enemies and mutualists and how mycorrhizal fungi modify the impact of enemies on plant community composition, diversity and productivity. I will take advantage of the global research network “BugNet” (bug-net.org), which was established to better understand the impact and interacting effects of invertebrate herbivores and fungal pathogens on plant communities, and how this impact depends on climatic or other abiotic variables. In this network, collaborators around globe set up experiments, where aboveground insect herbivores, molluscs and fungal pathogens are excluded from herbaceous communities. The experimental set up is ideal to further investigate how consumers interact and this PhD will explore the mechanisms behind these interactions by looking at how consumers affect belowground and phyllosphere microbial communities