Sweet sorghum (Sorghum bicolor [L.] Moench) a potential biofuel feedstock: Analysis of cultivar performance in the Mid-Atlantic

Sweet sorghum (Sorghum bicolor) was tested as a potential biofuel crop in the U.S. Mid-Atlantic. All studies were conducted on private farmland in Wicomico Co., on Maryland's Eastern Shore. In total, twelve cultivars were tested: Dale, Della, E2324, High Kane II, Keller, KN Morris, M81E, Mennonite, Simon, Sugar Drip, Theis and Topper 76-6. Eight cultivars were grown each year, over three years, and poorly performing cultivars were replaced. The five cultivars with the highest potential as biofuel feedstocks were Dale, Della, Keller, KN Morris and M81E. Biomass ranged from 52.9 to 64.1 Mg ha−1, juice volume from 14.0 to 22.8 Mg ha−1, Brix from 13.1 to 15.1 and theoretical ethanol yield from 1000 to 1149 L ha−1. Theoretical ethanol yield was ca. ⅓ that of grain corn grown in Maryland over the study period (2776–3798 L ha−1). Of these cultivars, Della, M81E and KN Morris had the highest grain yield (1.94–2.41 Mg ha−1). Further studies should focus on increasing ethanol yield through the improvement of agronomic practices, efficient juice extraction and the use of the “whole-crop” (juice, grain and bagasse) to generate ethanol. Potential problems for growers include lodging, particularly in areas with high winds, and grain loss to birds.