Researchers have discovered the signal that triggers plants to respond to drought stress. By using genetic modifications to trigger this pathway earlier, scientists could create drought-resistant crops. The study, just published in the journal Proceedings of the National Academy of Sciences, was led by a team at the Australian National University.
Drought has a huge impact on the economy and global food security. Plants do have ways to deal with drought stress, including producing protective compounds. This is often a delayed response, however, and occurs after the plant has already suffered severe damage. Drought conditions tend to affect crops such as wheat during the vulnerable flowering stages, leading to an overall drop in crop yields.
Researchers found that a phosphatase enzyme called SAL1 was responsible for signaling drought stress to plants. When this enzyme is inactivated, it triggers a chemical pathway that prompts the plant to make changes to deal with the lack of water in the environment. The team found that this signal was used in most plants, including important food crops such as wheat and rice.
Genetic modifications could be used to set off the signal pathway early, helping protect crops. The researchers are also developing a chemical spray that directly activates these signals. They have completed a computer model of SAL1 in order to identify similar compounds that could potentially be used in the spray. Now, with funding from the ANU Connect Ventures Discovery Translational Fund, they hope to create a spray that can be used the moment a drought starts. By protecting plants immediately, crops can be saved.
Developing drought-resistant crops is critical for maintaining consistent yields, especially in dry areas such as Australia. Now that scientists have identified the enzyme responsible for signaling drought stress to plants, it’s possible to develop ways to set off this pathway early. By triggering stress signals early, crops can be protected before they’ve suffered too much damage. Both genetic modifications and special chemical sprays are possibilities. The researchers have already received funding for these projects and hope to see results within the next two years.
Kai Xun Chan et al. Sensing and signaling of oxidative stress in chloroplasts by inactivation of the SAL1 phosphoadenosine phosphatase. Proceedings of the National Academy of Sciences (2016).