Plant hormones that help roots reach deeper water offer potential strategy for drought-tolerant crops

Scientists have discovered how plants adapt their root systems under drought conditions, growing rapidly into the soil to access deeper reservoirs.

Plant scientists at the University of Nottingham, in collaboration with Shanghai Jiao Tong University, are investigating how abscisic acid (ABA), a plant hormone known for its role in the desiccation response, affects the root growth angle of grains such as rice and maize. We have identified what to do. The results were published in Current Biology.

This study highlights how ABA and another important hormone, auxin, work together to shape root growth angles, providing potential for developing drought-tolerant crops with improved root system architecture. Provide potential strategies.

Drought poses a major threat to global food security, and strengthening crops’ ability to withstand water scarcity is critical. Drought, a major abiotic stress factor, has caused significant crop production losses of approximately $30 billion over the past decade. Given the predicted population of 10 billion people by 2050 and the severe depletion of fresh water, the development of drought-tolerant crops is of paramount importance.

Plants actively seek water, relying on their root system, which is their primary organ for interacting with the soil. In drought conditions, water is often depleted in the topsoil, leaving water only available in the deeper subsoil. Abscisic acid (ABA) plays an important role in helping plants adapt to these difficult conditions. This new study provides new insights into how ABA changes the angle of root growth, allowing plants to reach deeper subsoil in search of water.

The researchers discovered a new mechanism whereby ABA promotes auxin production, which enhances root gravitropism and causes them to grow at steeper angles in response to desiccation. Experiments revealed that plants with a genetic mutation that inhibits ABA production have shallower root angles and weaker root bending response to gravity than normal plants. These defects were associated with decreased root auxin levels. By adding auxin externally, the researchers restored normal root growth in these mutants, showing that auxin is key to this process.

This finding is consistent in both rice and maize, suggesting that this mechanism may apply to other cereals as well.

Dr. Rahul Bhosal, assistant professor in the School of Biological Sciences and one of the study’s lead authors, said: “Finding ways to address food insecurity is critical, and understanding the mechanisms that control plant growth will The more we do that, the closer we can get to a solution.” The idea is to design systems that help plants do this and improve crop yields during droughts. ”