Improving Crop Yields in a World of Extreme Weather Events

When plants encounter drought, they naturally produce abscisic acid (ABA), a stress hormone that helps them cope with the drought conditions.

Botanists have identified an inexpensive synthetic chemical, quinabactin, that mimics ABA. Spraying ABA on plants improves their water use and stress tolerance, but the procedure is expensive. Quinabactin now offers a cheaper solution.

Farmers in the United States witnessed record-breaking extremes in temperature and drought during the last two summers, causing worldwide increases in the costs of food, feed and fiber. Indeed, many climate scientists caution that extreme weather events resulting from climate change is the new normal for farmers in North America and elsewhere, requiring novel agricultural strategies to prevent crop losses.

Now a research team led by Sean Cutler, a plant cell biologist at the University of California, Riverside, has found a new drought-protecting chemical that shows high potential for becoming a powerful tool for crop protection in the new world of extreme weather. Named "quinabactin" by the researchers, the chemical mimics a naturally occurring stress hormone in plants that helps the plants cope with drought conditions.

All land plants have intricate water sensing and drought response systems that are tuned to maximize their fitness in the environments they live in. For example, plants in environments with low water grow slowly so that they do not consume more water than is available.

"But since farmers have always desired fast-growing varieties, their most valued strains did not always originate from drought-tolerant progenitors," explained Cutler, an associate professor of plant cell biology. "As a result, we have crops today that perform very well in years of plentiful water but poorly in years with little water. This dilemma has spawned an active hunt for both new drought-tolerant crops and chemicals that farmers might use for improving crop yield under adverse conditions."