The Chemical Ecology and Toxicology laboratory at Autonomous University of Barcelona studies the role of plant chemical defenses against herbivory in the context of biological invasions, and how rapid evolution occur as a result of changes in the abiotic and biotic environment.
The novel interactions established between exotic plants and native herbivores offers a great model systems to study the evolution of plant chemical defenses. During invasion, exotic plants can be released from their coevolved enemies from the native environment favouring the selection of those genotypes investing less in chemical defenses. However, invasive plants can be posteriorly colonized by native herbivores from the area of invasion. Because neither plants nor herbivores in these newly established interactions have coevolved together, the outcome that these relationships may have on the evolution of chemical defenses is mostly unknown.
We use the Senecio pterophorus (Asteraceae) as a model system to study post-invasive evolution of chemical defenses. This species is originary from South Africa and has colonized Australia and Europe (Catalonia and Italy). Senecio contains well-characterized chemical defenses, the pyrrolizidine alkaloids, that are highly toxic to invertebrates and vertebrates. We are studying whether S. pterophorus is rapidly evolving in the novel range by analyzing the differences in genetically-based plant traits between the native and the invasive populations, and their resistance of herbivores. We are also comparing the chemistry and associated herbivores on S. pterophorus in the invaded range with phylogenetically related Senecio species sharing the same habitat. These complementary approaches provide information not only about changes in chemical defenses and herbivory after plant invasion, but also about the relative decrease of herbivory compared to native species, which will be specially important on determining competitive abilities after invasion.
Key words: chemical defenses, herbivory, climate, evolution, phytochemistry, metabolomics, biological invasions, phylogeography
- Role of plant-herbivore interactions on the invasive capacity of the exotic species Senecio pterophorus. 2009-2011. Ministerio de Ciencia e Innovación (Spain). Ref. GCL2008- 02421/BOS. PI: Eva castells
- Post-invasive evolution of the exotic plant species Senecio pterophorus. 2012-2014. Ministerio de Economía y Competitividad (Spain). Ref. GCL2011-29205. PI: Eva Castells
- Agroecosystems Research group. 2009-2013. Generalitat de Catalunya (Catalonia). Ref. 2009 SGR1058. PI: Xavier Sans