Improving Sugarcane as a Bioenergy Crop in the U.S.

Sugarcane is one of the world’s most important crops.  Large-scale sugarcane-based ethanol production in Brazil, together with an impressive energy balance reported therein, has helped to generate interest in sugarcane as a bioenergy crop in the U.S.  An advantage of sugarcane is the production of free sugars in the juice that can be readily converted to ethanol and lignocellulosic residue (bagasse) that can be used as feedstock for such end products as cellulosic ethanol, syngas, steam, and electricity (cogeneration). While currently grown only as a sugar crop in Florida, Hawaii, Louisiana, and Texas, sugarcane and its relatives have potential as bioenergy crops in the southern U.S.  In 2007, three sugarcane varieties were released in Louisiana for use as feedstocks for the production of bioenergy.  These varieties were deemed unsatisfactory for sugar production due to their high fiber content, which interferes with sugar recovery.  Two of these high-fiber varieties are under evaluation in a broad region of the southern U.S.  Challenges associated with improving sugarcane as a dedicated bioenergy crop include, 1) defining what energy cane is in contrast to sugarcane, 2) maintaining parallel genetic improvement programs for both sugarcane and energy cane, and 3) improving traits and modifying cultural practices that would greatly broaden the adaptability of energy cane within the U.S.  Overcoming these challenges, classifying the range of germplasm available in the Saccharum genus, and the current status of the development of sugarcane as a viable bioenergy crop in the U.S. will be addressed in this presentation.