Plants subjected to a previous period of drought learn to deal with the stress thanks to their memories of the previous experience, according to a new study.
Scientists from the University of Nebraska-Lincoln discovered that plants which had experienced drought learnt to deal with the phenomenon much better the next time.
Scientists had conducted an experiment on Arabidopsis, a member of the mustard family considered an excellent model for plant research. They compared the reaction of two plants that were stressed by withholding water. Among the two plants, one had experienced the same kind of stress earlier whereas the other was experiencing it for the first time.
Scientists discovered that plant that had experience earlier bounced back quickly compared to the other. This shows that pre-stressed plants bounced back more quickly the next time they were dehydrated, whereas the non-trained plants wilted faster.
The team found that the trained plants responded to subsequent dehydration by increasing transcription of a certain subset of genes. During recovery periods when water is available, transcription of these genes returns to normal levels, but following subsequent drought periods the plants remember their transcriptional response to stress and induce these genes to higher levels in the subsequent drought stress.
This discovery may lead to breeding or engineering of crops that would better withstand drought, although practical applications of these findings in agriculture are years away, according to the researchers.
"The plants 'remember' dehydration stress. It will condition them to survive future drought stress and transplanting," Michael Fromm, scientist at the University of Nebraska-Lincoln, said in a statement.