Yang Zhao stands in a greenhouseYang Zhao found that engineering rice to produce high levels of the protein PYL9 can improve the crop's drought survival rate by 40 percent. (Photo by Tom Campbell)

"Die and let live" strategy dramatically increases drought resistance

By Natalie van Hoose - Published May 12, 2016

Purdue University researchers found that engineering plants to produce high levels of a protein known as PYL9 dramatically boosted drought tolerance in rice and the model plant Arabidopsis.

Under severe drought conditions, the transgenic plants triggered the death of their old leaves—a process known as senescence—to conserve resources for seeds and buds, a survival strategy some plant scientists refer to as "die and let live."

The study offers insights into the drought survival mechanisms of plants and presents a possible means of protecting crops from severe drought stress.

"This study shows that controlled senescence is good for plants under drought conditions," says Yang Zhao, first author of the study and research assistant in the Jian-Kang Zhu lab in the Department of Horticulture. "This combination of death and life is similar to a triage strategy. If old leaves die, then the buds and small leaves might gain life."

Zhao cautions, however, that the spike in survival rate does not mean the yield of the transgenic plants under drought conditions would equal that of conventional rice varieties under good growing conditions. The study did not test for yield.

"We still can't really solve the problem of drought," he says. "But we can make it better. In extreme drought conditions, even a bad yield would be better than nothing in terms of preserving human life."