Local adaptation to plant-plant interactions and consequences for establishment of invasive species: The example of the annual Erodium cicutarium in Germany and California
Final Report Abstract
As interspecific competition is known to affect plant fitness, plant-plant interactions may cause local genetic differentiation in some species, although evidence is sparse so far. Main hypothesis for the fellowship project was that in an annual grassland species known to be negatively affected by shading, gradients in the intensity of aboveground competition for light may lead to functional and genetic differentiation among populations. We sampled Erodium cicutarium in high and low competition environments and exposed field-collected seeds to experimental competition in a glasshouse experiment. In this experiment, we found highly significant effects of the competition treatment: Experimental competition induced a shade-avoidance response, which we interpret as a mixture of adaptive and passive plasticity. High competition intensity and high heterogeneity in competition experienced by maternal plants was coupled to greater reproductive and physiological efficiency in the next generation. These results indicate a functional differentiation of populations, which is in line with the main hypothesis. As we used field-collected seeds, this differentiation does not necessarily have a genetic basis, but instead may be due to maternal effects. Future studies using seeds raised under homogeneous conditions will have to clarify this.
Publications
- (2012) Richardson, D.M., Editor (2011) Fifty years of invasion ecology: the legacy of Charles Elton. - Schweizer Zeitschrift für Forstwesen 63: 284
Heger, T.
- (2013) The role of eco-evolutionary experience in invasion success. - NeoBiota 17: 57-74
Saul, W.-C., Jeschke, J. M. & Heger, T.
(See online at https://doi.org/10.3897/neobiota.17.5208) - (2013) Auswirkungen von Neobiota auf die Biodiversität - eine Frage des Maßstabs, der Artengruppen und ökologischen Mechanismen. - Berichte der Reinhold-Tüxen-Gesellschaft 25: 61–69
Kollmann, J., Heger, T. & Jeschke, J.
- (2013) Conceptual frameworks and methods for advancing invasion ecology. - Ambio 42: 527–540
Heger,T., Pahl, A. T., Botta-Dukát, Z., Gherardi, F., Hoppe, C., Hoste, I., Jax, K., Lindström, L., Boets, P., Haider, S., Kollmann, J., Wittmann, M. & Jeschke, J. M.
(See online at https://doi.org/10.1007/s13280-012-0379-x) - (2013) What biological invasions 'are' is a matter of perspective. - Journal for Nature Conservation 21: 93–96
Heger, T., Saul, W.-C. & Trepl, L.
(See online at https://doi.org/10.1016/j.jnc.2012.11.002)
