Tag: Henderson L.

The potential of enhancing stomatal kinetics to improve water use efficiency without penalty in carbon fixation

Optogenetic manipulation of stomatal kinetics improves carbon assimilation, water use, and growth

by Papanatsiou M., Petersen J., Henderson L., Wang Y., Christie J. M., Blatt M. R. (2019)

  1. M. Papanatsiou1,2, 
  2. J. Petersen2,*, 
  3. L. Henderson2, 
  4. Y. Wang1,3, 
  5. J. M. Christie2,†,‡, 
  6. M. R. Blatt1,2,3,†,‡

  1. Laboratory of Plant Physiology and Biophysics, Institute of Molecular, Cell and Systems Biology, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK.
  2. Plant Science Group, Institute of Molecular, Cell and Systems Biology, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK.
  3. Institute of Crop Science, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, China.

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In Science 363, Issue 6434, 1456-1459 – DOI: 10.1126/science.aaw0046 –

http://science.sciencemag.org/content/363/6434/1456

Speeding up stomatal responses

A plant’s cellular metabolism rapidly adjusts to changes in light conditions, but its stomata—pores that allow gas exchange in leaves—are slower to respond. Because of the lagging response, photosynthesis is less efficient, and excess water is lost through the open pores. Papanatsiou et al. introduced a blue light–responsive ion channel into stomata of the small mustard plant Arabidopsis. The channel increased the rate of stomata opening and closing in response to light. The engineered plants produced more biomass, especially in the fluctuating light conditions typical of outdoor growth.

Abstract

Stomata serve dual and often conflicting roles, facilitating carbon dioxide influx into the plant leaf for photosynthesis and restricting water efflux via transpiration. Strategies for reducing transpiration without incurring a cost for photosynthesis must circumvent this inherent coupling of carbon dioxide and water vapor diffusion.

We expressed the synthetic, light-gated K+ channel BLINK1 in guard cells surrounding stomatal pores in Arabidopsis to enhance the solute fluxes that drive stomatal aperture.

BLINK1 introduced a K+conductance and accelerated both stomatal opening under light exposure and closing after irradiation. Integrated over the growth period, BLINK1 drove a 2.2-fold increase in biomass in fluctuating light without cost in water use by the plant.

Thus, we demonstrate the potential of enhancing stomatal kinetics to improve water use efficiency without penalty in carbon fixation.