High Stalk Sugar Corn: A Potential Biofuel Crop for Canada

One of the most energy efficient systems of biofuel production uses the sugar extracted from sugarcane (Saccharum officinarum L.) for fermentation into ethanol; while sugarcane will not grow in Canada, corn (Zea mays L.), another C4 crop can. The overall objective of our study was to determine if there was corn germplasm, adapted to the short‐season regions of Canada, with high stalk sugar content. Thirty‐nine genotypes from diverse backgrounds were evaluated for stalk sucrose accumulation and associated traits (juice percentage, plant height, weight, and moisture) in field trials from 2007 to 2009. Genotypic differences for stalk sucrose and juice percentage were highly significant. Mean stalk sucrose ranged from 5.1 to 16.4 Brix (oBx) and fresh biomass from 45 to 135 Mg ha−1 suggesting the presence of exploitable genetic variation. Mean stalk sucrose concentration was significantly higher in plants where pollination was prevented. Calculated sucrose yield of experimental hybrids ranged from 4.3 to 6.0 Mg ha−1. At the current conversion efficiency, the products of sucrose and fresh biomass can be translated into 3600 L ha−1 ethanol plus 47 Mg ha−1 silage, indicating that this high stalk sugar corn (or “sugarcorn”) would be a valuable and an economically viable crop for Canada and elsewhere.