Scientists from our top-rated Biosciences department have uncovered a key mechanism in plant roots that helps them adapt to temporary water shortages.
Working with researchers across the UK and Europe, the team discovered that special proteins in plant cells respond to early signs of drought by changing their shape.
This change helps the plant adjust its root growth to avoid wasting energy in dry soil.
How plants adapt to dry conditions
The research reveals how plant roots detect water scarcity quickly using chemical signals called reactive oxygen species (ROS).
These signals cause a protein known as IAA3 to cluster together in a way that reduces root branching – a vital step to help the plant conserve resources until water becomes available again.
Faster responses than previously known
Until now, it was thought that plants responded to drought mainly through a slower hormone-based system involving abscisic acid (ABA), which takes many hours to activate.
This new study shows that ROS signals can act within just a few hours, giving plants a much faster way to sense and respond to changing soil conditions.
The researchers found that IAA3 acts like a switch in the root cells. When there's less water, ROS triggers IAA3 to group up (form "multimers") and stop the root from forming new branches.
This process helps the plant pause root growth until it finds moist soil again.
Hope for drought-tolerant crops
Understanding this faster drought-response system opens up new opportunities in agriculture.
If scientists can use this knowledge to breed or engineer crops that are better at responding to water shortage, it could lead to plants that use water more efficiently — an important step for farming in a changing climate.
This discovery shows how redox signals like ROS help in regulating plant growth according to the environment. It could one day help us design crops that cope better with drought.
