Sweet sorghum1(甜高粱) is primarily grown in the United States as a source of sugar for
syrup2(糖浆) and molasses. But the
sturdy(坚定的,强健的) grass has other attributes that could make it uniquely suited to production as a bioenergy crop, U.S. Department of Agriculture (USDA) studies suggest. Sorghum is an ideal candidate because of its drought
tolerance3,
adaptability4 to diverse growing conditions, low nitrogen fertilizer requirements, and high biomass (plant material) content, according to
molecular5 biologist Scott Sattler and
collaborator6 Jeff Pedersen with USDA's Agricultural Research Service (ARS). It also produces
soluble7 sugar that can be converted to biofuel.
Residual8 fibers9 left over from the juice extraction process also can be burned to generate electricity.
Sattler and Pedersen's studies of sorghum are part of a larger effort by ARS-USDA's principal intramural scientific research agency-to answer a government
mandate10 calling for the production of up to 36 billion gallons of biofuel by 2022. Approximately 15 billion gallons of that total will come from grain ethanol, with the remaining 21 billion gallons to come from other sources, or "feedstocks," including sorghum,
sugarcane(甘蔗), other grasses like switchgrass, and oilseed crops like
rapeseed(油菜籽) and soybean.
Sorghum and sugarcane are top candidates for production in the southeastern United States because they are complementary crops that can extend the biofuel production season and
utilize11 the same equipment, note Sattler and Pedersen, who work at the ARS Grain,
Forage12 and Bioenergy Research Unit in Lincoln, Neb. However, they are not the only team examining sweet sorghum's energy potential.
At the ARS Crop Genetics and Breeding Research Unit in Tifton, Ga., geneticist William Anderson and his colleagues are working to identify desirable sweet sorghum
genes13 and their functions so improved varieties can be developed. In studies, they selected 117 genotypes from the ARS sorghum germplasm collection at Griffin, Ga., and evaluated them for their ability to mature quickly and resist fall armyworms and the fungal disease anthracnose.