Standardization of nitrogen fertilizer rate for sugar yield optimization in sweet sorghum

Abstract

The recent skyrocketing of global fossil fuel prices
\ndriven by shrinking supplies in the face of rising demand
\nand increased concerns over environmental pollution
\nassociated with fossil fuel use triggered tremendous
\nefforts in exploring the use of alternative renewable fuel
\nsources particularly the transportation fuels worldwide.
\nEthanol is the numero uno biofuels currently produced
\nmainly from maize (Zea mays) and sugarcane
\n(Saccharum officinarum). Sweet sorghum (Sorghum
\nbicolor) is similar to grain sorghum, having fast growth,
\nhigh biomass production and wider adaptability and is
\nknown to have great potential in ethanol production
\n(Reddy et al. 2005). There is an increased interest in the
\nutilization of sweet sorghum for ethanol production in
\nIndia, the Philippines, China and USA, as its growing
\nperiod (about 4 months) and water requirement (8000 m3
\nover two crops) (Soltani and Almodares 1994) are 4
\ntimes lower than those of sugarcane (12–16 months and
\n36,000 m3 crop-1, respectively). To make sweet sorghum a
\nsustainable and profitable crop, there is a need for
\nstandardization of agronomic practices, apart from
\nbreeding high-yielding cultivars, which can contribute to
\nincreased yields resulting in higher returns to farmers.
\nApplication of fertilizers has a direct impact on crop
\nproductivity. Nitrogen (N) is one of the major nutrients
\nthat support crop growth and is the most responsive
\nnutrient required by sorghum (Singh et al. 1972). The
\npresent study was conducted at International Crops
\nResearch Institute for the Semi-Arid Tropics (ICRISAT),
\nPatancheru, India to standardize the optimum N dosage
\nfor the optimization of sugar yields in sweet sorghum.