How is drought affecting cereal plants such as wheat and barley?

Climate-related drought is a major physical stress that affects crop productivity. Currently, up to 45 per cent of the world’s agricultural land, where around 40 per cent of the world’s human population resides, is subjected to continuous or frequent drought.

Due to the worldwide impact of drought and associated stresses on crops, there is an urgent demand for a sustainable solution.

In a review paper published in the International Journal of Molecular Sciences, researchers at the University of Adelaide’s School of Agriculture, Food and Wine have summarised seven years of research published in more than 20 international journals, on the effect of drought on cereal plants such as wheat and barley.

This research has used mainly molecular biology techniques in combination with structural bioinformatics (how biological data is acquired, stored, analysed, and disseminated), and genetic engineering, along with classical plant physiology approaches.

“The knowledge we’ve discovered in this significant body of work holds promise for informed decisions on transcription factor applications to bioengineer plants with enhanced tolerance to drought and other abiotic stresses."Professor Maria Hrmova.

The group’s research has focused primarily on the role of cereal transcription factors during drought and how these proteins function in drought-affected plants. Transcription factors are multi-functional proteins that may simultaneously control numerous pathways during stress in plants. Consequently, transcription factors are powerful tools for genetic engineering, as their controlled expression can lead to the up or down regulation of genes under their control.

One of the project leaders, Professor Maria Hrmova (pictured) from the University’s School of Agriculture, Food and Wine, said: “The research involved subjecting cereal plants to drought and analysing the effect on plant growth and developmental processes.

“In doing so we were able to understand the physiological and molecular processes of how transcription factors may function in plants under drought, and were able to unravel structural mechanisms of several classes of transcription factors.

“We were able to understand how they bind specific sequences of DNA, known as cis-elements. Based on these DNA binding analyses, we could design modified proteins and test their function in plants.”

In several breakthrough studies, the researchers changed the way cereal plants responded to drought. This research also included the tailored design of variant transcription factors that could be used for engineering in plant biotechnology.

“The knowledge we’ve discovered in this significant body of work holds promise for informed decisions on transcription factor applications to bioengineer plants with enhanced tolerance to drought and other abiotic stresses,” said Professor Hrmova.

“The work on plant defence mechanisms controlled by transcription factors is ongoing.

"We look forward to continuing to contribute to knowledge that can assist the agricultural sector to combat the effects of an ongoing drought.”