Scientists have discovered how to potentially design root systems to grow deeper by altering their angle of growth to be steeper and reach the nutrients they need to grow.
It is believed that the discovery could also help develop new ways to capture carbon in soil.
In essence, researchers from the University of Nottingham and Bologna have discovered a key gene in barley and wheat that controls the angle of root growth.
Steeper root angle helps bury carbon deeper in soil as well as improving resilience in crops to drought stress.
Research on root systems
Members of the Nottingham team have discovered how a new gene (called Enhanced Gravitropism 1 or EGT1) normally controls root angle by stiffening the core of growing root tips, making it more difficult to bend downwards.
However, after this gene is disrupted, the team used x-ray micro CT imaging to reveal that every different type of root has a steeper angle.
Rahul Bhosale, assistant professor from the School of Biosciences and the Future Food Beacon at the University of Nottingham, who co-led the research, explained:
“Root angle controls how efficiently plants can capture water and nutrients. For instance, shallow roots best capture phosphate which accumulates in the topsoil region, while steeper roots are better for foraging for water and nitrate in deeper soil layers.
“Steeper roots are also important for helping bury carbon deeper into soil.
“Discovering genes like EGT1 and how they control root angle is critical for developing novel future crop varieties better able to capture nutrients and carbon.”
The international team includes researchers from the University of Adelaide, University of Bologna and Penn State University.
The Nottingham team was funded by ARPA-E, BBSRC Discovery Fellowship, European Research Council, Royal Society and University of Nottingham Future Food Beacon awards.
Plough
When asked if steepening the root angle of cereal crops would help individual plants to break through plough pans, the members of the research team supplied the following response:
“A steeper root angle could be beneficial if compact soil layers were thin enough to be penetrated and if deeper soil layers are looser. Steep roots can reach these layers while shallower roots might not.
“Alternatively, it could be counterproductive in soils that at depth are even more compacted. Steeper roots won’t be able to penetrate to reach deeper richer soil layers and due to steep angle can’t capture resources from the top layers.
“Overall there is some literature showing an existing link between root growth angles and soil strength, but it’s not clear whether those responses are due to adaptive plasticity or a consequence of the effect of compaction on root growth,” the researchers said.
