Biofuels are mostly produced from grains such as corn. In recent years, various types of wild grasses and other crops have been looked at to produce biofuels, but have yet to break through in a big way. A new study by the United States Department of Agriculture has uncovered a potential breakthrough candidate for biofuel expansion. It is sorghum, a grassy plant grown primarily in the southeastern United States as a source of sugar for syrup and molasses. Its sturdiness and resistance to drought make it ideal for the production of bioenergy.