Evaluation of the effects of elevated CO2 concentrations on the growth of cassava storage roots by destructive harvests and ground penetrating radar scanning approaches
Cassava (Manihot esculentaCrantz) production will need to be improved to meetfuture food demands in Sub‐Saharan Africa. The selection of high‐yielding cassavacultivars requires a better understanding of storage root development. Additionally,since future production will happen under increasing atmospheric CO2concentra-tions ([CO2]), cultivar selection should include responsiveness to elevated [CO2].Five farmer‐preferred African cassava cultivars were grown for three and a halfmonths in a Free Air CO2Enrichment experiment in central Illinois. Compared toambient [CO2] (~400 ppm), cassava storage roots grown under elevated [CO2](~600 ppm) had a higher biomass with some cultivars having lower storage rootwater content. The elevated [CO2] stimulation in storage root biomass ranged from33% to 86% across the five cultivars tested documenting the importance of this traitin developing new cultivars. In addition to the destructive harvests to obtain storageroot parameters, we explored ground penetrating radar as a nondestructive methodto determine storage root growth across the growing season.