When a plant encounters drought, it does its best to cope with this stress by activating a set of protein molecules called receptors（受体，感受器） . These receptors, once activated, turn on processes that help the plant survive the stress. A team of plant cell biologists has discovered how to rewire this cellular machinery to heighten the plants' stress response -- a finding that can be used to engineer crops to give them a better shot at surviving and displaying increased yield under drought conditions.

The discovery, made in the laboratory of Sean Cutler, an associate professor of plant cell biology at the University of California, Riverside, brings drought-tolerant crops a step closer to becoming a reality.

It's the hormones

When plants encounter drought, they naturally produce abscisic acid（脱落酸） , a stress hormone that helps them cope with the drought conditions. Specifically, the hormone turns on receptors in the plants, resulting in a suite of beneficial changes that help the plants survive. These changes typically include guard cells closing on leaves to reduce water loss, cessation（停止） of plant growth to reduce water consumption and myriad（无数的） other stress-relieving responses.

The discovery by Cutler and others of abscisic acid receptors, which orchestrate these responses, was heralded（通报，预示） by Science magazine as a breakthrough of the year in 2009 due to the importance of the receptor proteins to drought and stress tolerance.