With growing concerns over water tables falling globally and the potential crop insecurity that could stem from it—even the Indian government believes there has to be “more crop per drop”—the need to develop drought-resistant crop strains is pronounced. In this backdrop, the news that researchers at the University of California, Riverside, have developed an “on-off” mechanism to regulate the loss of water from plants during photosynthesis should excite advocates of biotechnological solutions for agriculture.
In 2009, the researchers had discovered the protein that senses abscisic acid (ABA), a plant hormone that regulates the opening and closing of stomata (pores on the leaves) through which water escapes during carbon dioxide absorption (for glucose-synthesis). In a report published in Nature earlier this week, the researchers detailed a protein-manipulation technique—involving a common crop fungicide, mandipropamid—that cuts water-loss. After identifying the ABA receptor site, the scientists studied all possible mutations at the site and tested all receptor mutations with a host of chemicals commonly used in agriculture. Mandipropamid exhibited potent affinity and caused one mutant receptor to change shape, thereby inhibiting ABA reception. Tomato hybrids expressed the engineered receptor and showed greater water retention on being sprayed with mandipropamid. While Syngenta, a Swiss agricultural company has acquired the patent rights for the technology and will carry out evaluation of efficacy, it will be countries embracing GM technology that will benefit from this once it is proved fit for field use.