New research has revealed the secret as to how plants sense moisture in the soil and adapt the shape of their roots to optimize acquisition. The science could be used to breed crops that are more adaptive to climate change conditions such as low rainfall.
The discovery could be the key to ensuring food security in arid and dry regions. The study was conducted as part of a collaboration between the universities of Nottingham and Durham.
Roots only branch after contact with moisture
Roots are the part of the plant that helps them take in water and nutrients from the soil. Water is essential to all plants growth.
However, in changing climatic conditions when average rainfall is down in many areas, this is very challenging.
It has previously been understood that root architecture was altered to acquire more moisture, but until now, exactly how that was done was not understood.
Master gene disabled in extreme conditions
A plants root forms a branch when it comes in direct contact with soil moisture using a process known as 'hydropatterning'.
Lead authors of the study Professor Malcolm Bennett of the University of Nottingham and Professor Ari Sadanandom from the Department of Biosciences at Durham University have discovered that hydropatterning is controlled by a branching master gene called ARF7.
They found that plants lacking ARF7 were no longer able to hydropattern.
The research shows that the gene stays active when roots are exposed to moisture ARF7 promoting growth and root branching, hover if the roots are exposed to air, ARF7 is modified and inactivated, blocking root branching.
Opportunity to develop plant resistance
Professor Sadanandom explained:
"Plants are relatively immobile and therefore their growth and development is very much dependent on their environment. Our research has identified the particular protein which can modify, and even inactivate root branching, therefore limiting plant growth and development."
"This is hugely exciting as it opens up the possibility for us to adopt this protein interaction and potentially develop plants that could continue to branch roots even in challenging conditions such as water scarcity."
Professor Bennett concluded: "Water is critical for plant growth, development and, ultimately, their survival. Surprisingly, understanding how plants sense water availability has eluded scientists until now."
"By studying how plant roots modify their branching in response to water availability, we have uncovered a novel molecular mechanism. This represents a major step forward and opens the way for breeders to develop new crops better adapted to climate change and helping deliver global food security."
The world must find ways to sustainably feed the population
This ambitious target is hampered by the impact of climate change which may be causing reduced rainfall in some places. The research could assist in the development of agricultural plants that can be more resistant to low water conditions.