Sorghum: A Multipurpose Bioenergy Crop

Abstract

Bioethanol and biodiesel produced from renewable energy sources are gaining importance in light of volatile fossil fuel prices, depleting oil reserves, and increasing greenhouse effects associated with the use of fossil fuels. Among several alternative renewable energy sources, energy derived from plant biomass is found to be promising and sustainable. Sorghum [Sorghum bicolor (L.) Moench] is a resilient dryland cereal crop with wide adaptation having high water, nutrient, and radiation use efficiencies. This crop is expected to enhance food, feed, fodder, and fuel security. Sweet sorghum is similar to grain sorghum but has the ability to accumulate sugars in the stalks without much reduction in grain production. Hence, it is used as a first-generation biofuel feedstock, where the grain and stalk sugars can be used for producing bioenergy, while energy sorghum or biomass sorghum is increasingly viewed as a potential feedstock for lignocellulosic biofuel production. Although the commercial use of sweet sorghum for bioethanol production has been demonstrated in China and India, the viability of large-scale lignocellulosic conversion of sorghum biomass to biofuels is yet to be demonstrated. This chapter dwells on sorghum feedstock characteristics, biofuel production models, sustainability indicators, and commercialization.

Treated urban wastewater irrigation effects on bioenergy sorghum biomass, quality, and soil salinity in an arid environment

“…In general, holocellulose content increased with salinity and time over 3 years. Our results for holocellulose concentrations agree well with the range of 43% to 54% reported for different types of sorghum by Rao et al (). Our energy sorghum samples contained 4.6% to 6.6% lignin and 6.2% to 12.6% ash content (Figure c,d).…”

“…Our energy sorghum samples contained 4.6% to 6.6% lignin and 6.2% to 12.6% ash content (Figure c,d). Although the reported range for acid insoluble lignin (of 4.63% to 16.82%) in the literature compares well with our numbers, the ash content in our study was much higher than the range reported in the literature (1.83% to 3.2%), which could be due to the elevated salinity of the soils that were used to grow the energy sorghum (Rao et al, ). The above results indicate that biomass quality of energy sorghum grown on degraded saline land with marginal water was similar to that produced on nonsaline land.…”

“…Energy sorghum is a type of high biomass sorghum that has a long vegetative growth phase. Consequently, energy sorghum has greater light interception and higher radiation use efficiency (Rao et al, ). It yields more than twice the biomass of grain sorghum ranging between 15 and 40 Mg ha −1 (Packer & Rooney, ).…”

“…In addition to greater productivity, energy sorghum is drought and salt tolerant (Promkhambut, Younger, Polthanee, & Akkasaeng, ). Energy sorghum's theoretical ethanol yield is at least 25% higher than that of grain sorghum (Rao et al, ). A type of forage sorghum sudangrass ( Sorghum bicolor var.…”

Evaluation of Seed Quality Attributes of Sorghum Germplasm Accessions from Eastern, Coastal and Nyanza Regions, Kenya

“…Sorghum (Sorghum bicolor (L.) Moench) is an important cereal grain used and grown in semi arid areas as food for many families due to its nutritive value (Rao et al, 2016;FAO, 2018). The ability of sorghum to adapt to drought, salinity and high temperatures makes it a critical crop in the dry regions where other cereal crops produce low yields (Mamoudou, 2006).…”