Evolution of stomatal responsiveness to CO(2) and optimization of water-use efficiency among land plants
- PMID: 19402882
- DOI: 10.1111/j.1469-8137.2009.02844.x
Evolution of stomatal responsiveness to CO(2) and optimization of water-use efficiency among land plants
Abstract
The stomata of angiosperms respond to changes in ambient atmospheric concentrations of CO(2) (C(a)) in ways that appear to optimize water-use efficiency. It is unknown where in the history of land plants this important stomatal control mechanism evolved. Here, we test the hypothesis that major clades of plants have distinct stomatal sensitivities to C(a) reflecting a relatively recent evolution of water-use optimization in derived angiosperms. Responses of stomatal conductance (g(s)) to step changes between elevated, ambient and low C(a) (600, 380 and 100 micromol mol(-1), respectively) were compared in a phylogenetically and ecologically diverse range of higher angiosperms, conifers, ferns and lycopods. All species responded to low C(a) by increasing g(s) but only angiosperm stomata demonstrated a significant closing response when C(a) was elevated to 600 micromol mol(-1). As a result, angiosperms showed significantly greater increases in water-use efficiency under elevated C(a) than the other lineages. The data suggest that the angiosperms have mechanisms for detecting and responding to increases in C(a) that are absent from earlier diverging lineages, and these mechanisms impart a greater capacity to optimize water-use efficiency.
References
-
- Ainsworth EA, Rogers A. 2007. The response of photosynthesis and stomatal conductance to rising [CO2]: mechanisms and environmental interactions. Plant, Cell & Environment 30: 258-270.
-
- Berner RA. 2006. GEOCARBSULF: A combined model for Phanerozoic atmospheric O2 and CO2 Geochimica et Cosmochimica Acta 70: 5653-5664.
-
- Betts RA, Boucher O, Collins M, Cox PM, Falloon PD, Gedney N, Hemming DL, Huntingford C, Jones CD, Sexton D et al . 2007. Projected increase in continental runoff due to plant responses to increasing carbon dioxide. Nature 448: 1037-1041.
-
- Betts RA, Cox PMSE, Lee SE, Woodward FI. 1997. Contrasting physiological and structural vegetation feedbacks in climate change simulations. Nature 387: 796-799.
-
- Brodribb T, Holbrook N. 2004. Stomatal protection against hydraulic failure: a comparison of coexisting ferns and angiosperms. New Phytologist 162: 663-670.
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