Multiple Benefits of Intercropping Cowpea in the Solar Corridor Cropping System.

The solar corridor crop system (SCCS) is designed for improved crop productivity by using broad strips (corridors or skip rows) that promote highly efficient use of solar radiation and ambient carbon dioxide by C-4 plants including corn. In addition to improved productivity of corn, the solar corridor planted with low-growing grain crops provide supplemental grain, forage or conservation benefits. Field trials in 2014, 2015 and 2016 on a Mexico silt loam (fine, smectitic, mesic Vertic Epiaqualf) in mid-Missouri revealed that an integrated cowpea corridor crop provided ≈ 2 T ha^-1 of dry biomass at 3% N content. Dry grain yields of ≈ 1000 kg ha^-1 provide an additional protein source (25% protein) for use in human or livestock diets. The vegetative biomass offers supplemental protein for livestock grazing corn stover in the field as well as providing conservation benefits in reducing soil erosion and serving as a carbon source for soil microbial activity and soil organic matter buildup. Integrating cowpea in the SCCS offers multiple benefits of supplemental grain and forage as well as soil conservation that are not provided by conventional mono-cropping of corn.