Both the authors contributed equally to this work.
Stomatal innovation and the rise of seed plants
Article first published online: 23 OCT 2011
© 2011 Blackwell Publishing Ltd/CNRS
Volume 15, Issue 1, pages 1–8, January 2012
How to Cite
McAdam, S. A. M. and Brodribb, T. J. (2012), Stomatal innovation and the rise of seed plants. Ecology Letters, 15: 1–8. doi: 10.1111/j.1461-0248.2011.01700.x
- Issue published online: 1 DEC 2011
- Article first published online: 23 OCT 2011
- Editor, Elsa Cleland Manuscript received 8 July 2011 First decision made 4 August 2011 Second decision made 8 September 2011 Manuscript accepted 20 September 2011
- plant evolution;
- water use efficiency
Ecology Letters (2011) 14: 1–8
Stomatal valves on the leaves of vascular plants not only prevent desiccation but also dynamically regulate water loss to maintain efficient daytime water use. This latter process involves sophisticated active control of stomatal aperture that may be absent from early-branching plant clades. To test this hypothesis, we compare the stomatal response to light intensity in 13 species of ferns and lycophytes with a diverse sample of seed plants to determine whether the capacity to optimise water use is an ancestral or derived feature of stomatal physiology. We found that in seed plants, the ratio of photosynthesis to water use remained high and constant at different light intensities, but fern and lycophyte stomata were incapable of sustaining homeostatic water use efficiency. We conclude that efficient water use in early seed plants provided them with a competitive advantage that contributed to the decline of fern and lycophyte dominated-ecosystems in the late Paleozoic.