One of the most intriguing questions around herbivore defense is whether the amount of chemical defense produced by plants changes along rainfall gradients. Predictions in this regard are equivocal, suggesting either an increase of chemical defenses (glucosinolates) under more favorable conditions where herbivore pressure is deemed to be larger, or that under stressful conditions plants are more vulnerable to herbivore damage and thus a high level of constitutive defenses is desirable. Overall evidence for effects of drought on allelochemicals has been contradictory (Tariq et al. 2012) and little is known about genetically determined differences in glucosinolate levels in wild Brassicaceae that may constitute long-term evolutionary adaptations to distinct climatic conditions. Following up from a previous experiment (Metz et al. 2014), we test in a greenhouse experiment whether production of glucosinolates is influenced by water availability or by seed origin of a Brassicacea growing along a steep climate gradient in the Eastern Mediterranean region.
This project is part of the SPP Priority Program -Adaptomics.
Main Investigator: Katja Tielbörger
Collaborators:
Sara Tomiolo
Johannes Metz (University of Potsdam)
Caroline Müller (University of Bielefeld)
