Salk Tests Deep-Root Soybeans for Carbon Storage

Early this month Ashish Rajurkar and colleagues excavated a large clod of soil around a modified soybean plant at a Champaign, Illinois research field to display its vertical root profile. Salk Institute researchers engineered the plants so roots grow up to a meter deeper than standard varieties. An $18 million grant from the Bezos Earth Fund is funding the field trials. The team identified 347 genes linked to root growth and carbon storage through a genome encyclopedia project that began six years ago and catalogued hundreds of soybean and sorghum accessions from around the world. Preliminary data suggest up to 30 percent more carbon accumulated in the top 30 centimeters of soil. Wolfgang Busch said, "We need to prove that deeper roots can reliably store carbon without compromising yield." Trials will measure carbon sequestration, root growth, crop yields, resilience to climate stress, and scalability. Open questions include how much carbon is stored under real farming conditions, how long it remains underground, and whether the crops can be scaled without sacrificing commercially viable yields.