A new study has shown how engineering stomata could help to improve crop performance in future climate scenarios where CO2 levels are expected to be higher.
Stomata (small pores on the leaf surface) control water loss from plants and regulate the uptake of carbon dioxide to drive photosynthesis.
Opening of the stomata involves cells around the pores inflating as they accumulate water. Similar to a balloon, the final size and shape of the cells is determined not only by the pressure built up in the cells but also by the mechanical properties of the walls that surround them.
In the paper ‘Altering Arabinans Increases Arabidopis Guard Cell Flexibility And Stomatal Opening’ published in Current Biology, scientists, from the University of Sheffield’s School of Biosciences, show that the mechanical properties of the cells that form the stomata (guard cells) depends on their chemical composition, in particular the presence of a polymer containing a specific sugar, arabinan.
The researchers engineered guard cells with an increased level of arabinan polymer and showed that this led to cells which were more flexible, so that the stomata opened more widely.
“Under present-day CO2 levels this leads to leaves which gain more CO2 but also lose more water than standard stomata,” said Professor Andrew Fleming.
“However, under future conditions of higher CO2 levels such stomata are predicted to show a better trade-off, being able to get more CO2 into the plant for about the same water loss as conventional stomata.
“Our study highlights engineering stomata could be a route to improved crop performance in future climate scenarios.”
The work involved a collaboration between plant scientists at The University of Sheffield and computational biologists at the John Innes Institute, Norwich. The work was funded by the Biotechnology & Biological Sciences Research Council (BBSRC).
The Sheffield research team included first authors Sarah Carroll, a PhD student supported by the White Rose BBSRC Doctoral Training Program in Mechanistic Biology and BBSRC Discovery Fellow, Sam Amsbury, as well as Professors Julie Gray and Andrew Fleming.