Postdoctoral Associate Donald Danforth Plant Science Center St. Louis, Missouri
Body of Abstract: An estimated 35% of cultivated land in the Corn Belt has completely lost its carbon-rich A-horizon. Cover crops are one promising approach towards mitigating soil erosion and improving soil health. Cover crops are grown during normally fallow periods between cash crop growing seasons and provide beneficial ecosystem services, such as soil structure remediation, soil microbial diversification, and nutrient recycling. Roots and their interactions with the surrounding soil are key to a plant's ability to perform ecosystem functions. However, there is a lack of cover crop root data. To address this knowledge gap, we performed aboveground and belowground phenotyping to evaluate the field performance of 22 winter cover crop cultivars across the Poaceae, Fabaceae, and Brassicaceae families grown in O’Fallon, Missouri. Canopy imaging revealed significant differences in winter hardiness and canopy cover throughout the growing season. The most winter hardy species, cereal rye and winter triticale, produced similar amounts of shoot and root biomass. However, winter triticale formed thicker roots and produced more root biomass at deeper soil depths than cereal rye. Significant differences in rooting behavior were also observed among clover and brassica cultivars. These results suggest that root traits should be considered during cover crop selection and breeding. I will also briefly highlight efforts to characterize 3D root system architecture traits using a gel-imaging system as well as collaborative efforts to employ remote sensing technologies to model carbon and nitrogen cycling in cover crop systems at a field scale. A better understanding of how cover crop root system architecture contributes to their ecosystem functions will enable the design of more sustainable agricultural systems