A research team at the University of Illinois at Urbana-Champaign has engineered the tobacco plant to conserve water without compromising yield for the first time. The researchers found that increasing the expression of a key signaling protein called Photosystem II Subunit S (PsbS) can improve the water-use efficiency by up to 25%. Increasing the amount of PsbS relays a signal that there is insufficient light energy for photosynthesis, thus triggering the stomata to partially close. This reduces the rate of transpiration while still allowing the absorption of carbon dioxide. The next step of this research is to apply these findings to other food crops and to test their effectiveness in water-scarce conditions.

This research has the potential to address the imminent problem of water scarcity. Having food crops that require less water will allow us to better allocate water resources and to be able to rely on productive crop yields even during dry seasons. This breakthrough, combined with other studies on increasing crop yields, will pave the way to meeting the increasing demand for food now and in the future.