Abstract

Sweet sorghum (Sorghum bicolor (L.) Moench) has a good potential for ethanol production in Ethiopia. However, continual supply of feed stock to the distillery is one of the major constraints in sweet sorghum-based ethanol and grain yield productions. A study was carried out in Ethiopia during the 2015 to 2016 crop seasons to determine the performance of sweet sorghum genotypes for their stability or specific adaptability under contrasting fertilizer rates across environments. All agronomic characters were varied with the genotypes and environments. Grain yield, panicle weight and plant height were also significantly varied with fertilizations, but other agronomic characters were not varied with fertilizations. The ethanol yield and quality components varied with genotypes, environments and fertilizations, but brix % was not varied with fertilizations. The genotypes, E36-1, ICSR 93034 and IESV 92207 DL, produced greater estimated sugar, ethanol, juice and fresh stalk yield. The genotype, IESV 92207 DL, was the superior genotypes in grain yield and yield related traits, although it was second in brix % and ethanol yield followed by E36-1. At phenotypic and genotypic levels, grain yield was positive and significant correlations with panicle weight and panicle width. There was positive and significant (p<0.01) correlations between ethanol, juice, sugar and fresh stalk yields at both levels, this indicates the merits of these quality characters to improve ethanol yield.

Keywords: Brix; Ethanol; Sugar; Sweet sorghum; Genotypes; DAP fertilizer; Interactions; Urea