Root proliferation and seed yield in response to spatial heterogeneity of below-ground competition
Article first published online: 12 SEP 2005
Volume 168, Issue 2, pages 401–412, November 2005
How to Cite
O'Brien, E. E., Gersani, M. and Brown, J. S. (2005), Root proliferation and seed yield in response to spatial heterogeneity of below-ground competition. New Phytologist, 168: 401–412. doi: 10.1111/j.1469-8137.2005.01520.x
- Issue published online: 12 SEP 2005
- Article first published online: 12 SEP 2005
- Received: 24 March 2005 Accepted: 13 June 2005
- below-ground competition;
- game theory;
- pea (Pisum sativum);
- root proliferation;
- tragedy of the commons
- • Here, we tested the predictions of a ‘tragedy of the commons’ model of below-ground plant competition in annual plants that experience spatial heterogeneity in their competitive environment. Under interplant competition, the model predicts that a plant should over-proliferate roots relative to what would maximize the collective yield of the plants. We predict that a plant will tailor its root proliferation to local patch conditions, restraining root production when alone and over-proliferating in the presence of other plants.
- • A series of experiments were conducted using pairs of pea (Pisum sativum) plants occupying two or three pots in which the presence or absence of interplant root competition was varied while nutrient availability per plant was held constant.
- • In two-pot experiments, competing plants produced more root mass and less pod mass per individual than plants grown in isolation. In three-pot experiments, peas modulated this response to conditions at the scale of individual pots. Root proliferation in the shared pot was higher compared with the exclusively occupied pot.
- • Plants appear to display sophisticated nutrient foraging with outcomes that permit insights into interplant competition.