Plants 'remember' droughts to prepare

LINCOLN, Neb., March 15 (UPI) -- Plants can "remember" drought and change responses to the stress to survive, a finding that could lead to more drought-resistant crops, U.S. researchers say.

The study confirms the scientific basis for what home gardeners and nursery professionals have long known, that transplants do better when water is withheld for a few days to "drought harden" them before the move, they said.

"This phenomenon of drought hardening is in the common literature but not really in the academic literature," Michael Fromm, a University of Nebraska-Lincoln plant scientist, said. "The mechanisms involved in this process seem to be what we found."

The researchers compared the reaction of plants that had been previously stressed by withholding water to those not previously stressed and found the pre-stressed plants bounced back more quickly the next time they were dehydrated, a university release reported.

The pre-stressed plants responded to dehydration by increasing transcription of a certain subset of genes, the scientists said, and in subsequent drought periods the plants remember their transcriptional response to stress and induce these genes to higher levels.

"The plants 'remember' dehydration stress. It will condition them to survive future drought stress and transplanting," Fromm said.