Chemical Ecology of Plant-herbivore Interactions

Plants produce a puzzling diversity of defensive chemicals in their struggle to deter herbivorous enemies. Complex chemical mixtures may present defensive advantages over single compounds, for example via multi-target toxicity or compound-compound facilitation. Chemical diversification is therefore considered a strategy to escape coevolved herbivores. At the same time, such diversification must be costly to the plant, in terms of both raw building blocks and maintenance costs for increasingly complex synthesizing machinery.

We aim to elucidate the selective forces that drive chemical diversification. We use a newly established model plant system and employ a combination of experimental ecology and different techniques including metabolomics, transcriptomics, and phylogenetic comparisons. In a two-pronged approach, we focus on the defensive benefits of diverse chemical mixtures via altered feeding behavior and success of generalist and specialist herbivores, as well as on the cost of diversification in terms of negative impact on plant growth and reproduction. Ultimately, we will thus be able to link variation in genes and metabolites to success in a variable and changing environment.

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  Zuest, Tobias; Agrawal, Anurag A. 
  FUNCTIONAL ECOLOGY 30 (4): 547-556 APR 2016 Article (Details)
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• Evolution of cardiac glycosides in Erysimum spp.
• Molecular mechanisms of phytochemical diversification
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• Herbivore tolerance to basal and novel defenses
• Sequestration of plant toxins and higher-trophic interactions

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