Sugar Crops for Biofuel/bioproduct Production

A USDA funded grant to the LSU AgCenter program to develop crops that can be used for biofuel production across the Southern United States to supply significant quantities of feedstocks for the next generation biofuel/bioproduct industries also offered the opportunity to improve local farm incomes, create manufacturing jobs as well. This program, directed by the LSU AgCenter, is a multi-researcher, multi-unit program that utilizes a wide variety of talents to develop new crops that can be produced sustainably and the technologies to locally convert them to fermentable sugars and biomass. The major constraints on the chosen crops were the ability to tolerate the wide variety of climatic conditions that exist between North and South Louisiana and the need for staggered harvest schedules such that crops can be delivered continuously to processing facilities over a major portion of a year.  Two crops, similar in structure and containing fermentable sugars, energycane and sweet sorghum, were chosen for development. Energycane is a variant of sugarcane which is high in fiber and low in sugar containing juice and sweet sorghum, a relative of grain sorghum which produces less seed and also contains a sugar juice. Energycane is a perennial crop and sweet sorghum is an annual crop. Both crops can be harvested and processed in a manner similar to sugarcane. The fermentable sugars present in these juices could support rapid development for biofuel or any fermentation based bioproduct, with lignocellulosic sugars phasing in as conversion technologies develops. The two chosen crops appear to be productive on marginal or underutilized land such that they won’t impact current crops. We are now in a position to answer key questions as to the utility of these crops as biofuel feedstocks.  Processing of these crops post- harvest, using standard technologies, produces sugar syrups which are storable and contain high contents of fermentable sugars and biomass. The biomass is suitable both for power generation and can be converted to fermentable sugars using technologies that have been developed for converting corn stover to fermentable sugars. The value of these syrup sugars should be competitive with the value of sugars in sugarcane molasses.