Salk Tests Deep Rooted Soybeans for Drought Resilience and Soil Carbon

Salk Institute researchers are field testing soybean plants engineered to develop deeper root systems, a trait they hope can help crops reach water during drought while moving more plant carbon below ground. The work has moved beyond controlled environments into trials in Illinois, Missouri, Kansas and Iowa, where yield, drought response and soil carbon can be measured under farm conditions.

At the University of Illinois Urbana Champaign, the trial includes a movable canopy that controls how much rain reaches the crop. Underground cameras and sensing equipment let research partners monitor root growth and changes in soil carbon, giving the team a way to test whether laboratory traits persist under variable weather and soils.

The project follows roughly six years of genomic work across diverse crop lines. Researchers identified 347 genes associated with root architecture and carbon storage, then used that information to develop plants with steeper and larger root systems. Soybean is one of several crops in the broader Harnessing Plants Initiative.

The biological case rests on both root depth and root chemistry. Deeper roots can place carbon farther below the surface, where it may be less exposed to cultivation, while larger roots leave more plant material in the soil. The team is also seeking higher levels of suberin, a carbon rich compound that breaks down more slowly than many other plant tissues.

Drought resilience is the most direct potential farm benefit. Researchers expect deeper roots to reach moisture below the topsoil when rainfall is limited, although the field trials still need to show whether that advantage holds without reducing yield. Root systems have historically received less attention from breeders than above ground traits, so the tradeoffs remain uncertain.

Earlier laboratory work led the Salk team to estimate that one hectare of deeper and larger rooted soybeans might store an additional metric ton of carbon dioxide per year. That is a research estimate, not a demonstrated field result. Actual storage will depend on soil conditions, root depth, management practices and how long the carbon remains underground.

An 18 million dollar grant from the Bezos Earth Fund is supporting the field work and efforts to move successful traits toward commercial use. Large scale adoption would require seed company participation, regulatory clearance where needed and a clear economic case for growers, especially if the plants are expected to compete with established high yielding varieties.

The current trials matter because they test two claims at the same time, climate resilience for the crop and durable carbon storage for the soil. Initial field results were expected during autumn 2026. Until those measurements are available, the technology should be viewed as a promising production research program rather than a proven carbon removal system.