Stomatal control in early land plants

 

Land plants acquired stomatal control early in their evolutionary history

by Ruszala E. M., Beerling D. J., Franks P. J., Chater C., Casson S. A., Gray J. E., Hetherington A. M. (2011)

in Current Biology, 21: 10305. – doi: 10.1016/j.cub.2011.04.044. Epub 2011 Jun 9. –

https://www.ncbi.nlm.nih.gov/pubmed/21658945

Abstract

Stomata are pores that regulate plant gas exchange [1]. They evolved more than 400 million years ago [2, 3], but the origin of their active physiological responses to endogenous and environmental cues is unclear [2-6]. Recent research suggests that the stomata of Lycophytes and ferns lack pore closure responses to abscisic acid (ABA) and CO(2).

This evidence led to the hypothesis that a fundamental transition from passive to active control of plant water balance occurred after the divergence of ferns 360 million years ago [7, 8].

Here we show that stomatal responses of the lycophyte Selaginella [9] to ABA and CO(2) are directly comparable to those of the flowering plant Arabidopsis [10].

Furthermore, we show that the underlying intracellular signaling pathways responsible for stomatal aperture control are similar in both basal and modern vascular plant lineages.

Our evidence challenges the hypothesis that acquisition of active stomatal control of plant carbon and water balance represents a critical turning point in land plant evolution [7, 8].

Instead, we suggest that the critical evolutionary development is represented by the innovation of stomata themselves and that physiologically active stomatal control originated at least as far back as the emergence of the lycophytes (circa 420 million years ago) [11].

Advertisements

Published by

Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s