Swiss scientists identify root barrier that helps plants withstand drought

In Switzerland, thale cress can be found growing wild in fields, meadows and along forest paths mainly in canton Ticino. Heiti Paves / Dreamstime.com

Researchers in Switzerland have discovered a mechanism that enables plants to store water more efficiently and better tolerate drought – an advance that could help strengthen global food security.

Thale cress (Arabidopsis thaliana) is a master of adaptation. This small wild plant has no direct agricultural value, yet it is well known in scientific circles. Its availability in nature, short life cycle and small size make it a particularly interesting subject for researchers.

To better understand how plants respond to water scarcity, scientists from the University of Geneva and the University of Lausanne have examined 284 varieties of thale cress collected worldwide. Their study was published in Nature Plants External linkjournal last month.

The research focused on the presence of suberin, a naturally occurring compound found in plant roots and bark.

“Suberin allows a plant to adjust its ability to regulate exchanges with the soil. It helps retain water when scarce and regulates the uptake of minerals present in the soil,” explained Marie Barberon, an associate professor at the Department of Plant Sciences at the University of Geneva, who led the study.

The study found that varieties of thale cress from warmer, drier regions tend to develop thicker suberin layers in their roots.

A special gene

Until now, suberin had no known function in plants. But for the first time researchers have discovered that a gene called SUBER GENE1 (SBG1) regulates the formation of suberin in root tissues.

Plants with more active versions of SBG1 form more protective barriers, while less active versions show weaker resistance to environmental stress.

The discovery could have important implications beyond laboratory research.

“The gene is conserved across different plants,” explains Barberon. “It would be interesting to see whether the gene does the same in plant species of agronomic interest, like tomatoes or wheat. We could identify natural gene variants that help plants adapt better to their environment through suberin.”

This discovery opens up new approaches to developing crops better suited to a warming and drying climate.

Adapted from German with AI/sb/ts