ABSTRACT
Sugarcane (a complex hybrid of Saccharum spp.) is cultivated in several parts of the world, primarily for sugar but also for the production of bioenergy in the form of electricity or ethanol. High biomass with C4 photosynthesis system and sucrose accumulation in the sugarcane stem (Fig. 1) makes it a favourable feedstock for bioenergy production. Brazil is the major sugarcane-producing country in the world with a total production of 631.8 million tons in 2014 (EPE 2015). In Brazil, sugarcane is used for both sugar production and ethanol production. In 2014, sugar production was 35.4 million tons and ethanol production was 28.5 Mm3. There has been 58% increase in energy production from sugarcane products in the last ten years. Bioenergy from sugarcane is second highest after petroleum and oil products in Brazil. In the United States, sugarcane is cultivated on approximately 370 000 ha (USDA 2016) and is used entirely for sugar production as there is no commercial cultivation of sugarcane for ethanol production yet. Sugarcane bagasse is used for electricity production through cogeneration plants in the sugar mills. Sugarcane breeding programmes in the United States are working to improve germplasm not only for high sucrose but also for high biomass and high fibre (also called energy cane; Fig. 2) in anticipation of future use of sugarcane in lignocellulosic ethanol production. High biomass, fast growth, low input cost and high energy output are some of the important characteristics of lignocellulosic feedstock. Among the several crops tested for the above
attributes, sugarcane has most successfully fit into these requirements (Waclawovsky et al. 2010). Energy cane cultivation for bioenergy would also make it possible to avoid competition between food and fuel crops.
