Plants could fight climate change by growing bigger roots
Plants and algae around the planet absorb some vast amounts of CO2 from the air each year, yet there’s a natural limit to how much they can do so as to reduce the amount of excess CO2 still in the atmosphere.
Science can help out, or so many scientists believe. Last year a team of biochemists at the Max Planck Institute for Terrestrial Microbiology in Marburg, Germany, succeeded in re-engineering the way plants, algae and various micro-organisms turn CO2 into fuel by making the process around 25% more energy efficient and significantly faster.
Now another team of scientists from the Salk Institute for Biological Studies in the United States is working on another way to harness plants’ carbon-absorbing natural abilities: this time their ability to capture carbon from the air and store it underground. Plants do that in their root systems so the larger those systems are and the deeper they go, the more CO2 plants can potentially lock up and store, explain the scientists in a study published in the journal Cell.
To understand the process of root formation, the experts examined the genetic and molecular mechanisms involved. In the process, they have discovered a gene that influences whether a plant’s roots grow deep down into the earth or remain shallow in the soil.
By manipulating that gene, we could cause cultivated plants to develop more robust and deeper roots, which would enable them to store larger amounts of carbon underground.
The researchers focused on a plant called thale cress (Arabidopsis thaliana). “In order to better view the root growth, I developed and optimized a novel method for studying plant root systems in soil,” explains the study’s first author Takehiko Ogura, a postdoctoral fellow. “The roots of A. thaliana are incredibly small so they are not easily visible, but by slicing the plant in half we could better observe and measure the root distributions in the soil.”
In the plant one gene called EXOCYST70A3, Ogura and his colleagues discovered, is responsible for regulating root system architecture. When they tampered with this gene in the lap, the scientists found plants started growing larger roots that went deeper into the soil.
Their work isn’t done yet, however. It’s one thing to do this in the lab and another to do it on a large-enough scale across cultivated farmlands so as to reduce the levels of CO2 in the atmosphere. Still, the hope is that we might be able to boost cultivated plants’ abilities in storing carbon in order to help us fight climate change.
“We hope to use this knowledge of the auxin pathway as a way to uncover more components that are related to these genes and their effect on root system architecture,” says Wolfgang Busch, an associate professor at Salk’s Plant Molecular and Cellular Biology Laboratory.
“This will help us create better, more adaptable crop plants, such as soybean and corn, that farmers can grow to produce more food for a growing world population,” he adds.
