Bioethanol obtained from soluble sugars in sweet sorghum, influencing properties and their interrelationships

The depletion of fossil fuels, the rising cost of energy and the associated environmental damage have prompted a shift towards the utilisation of renewable and clean energy sources. Sweet sorghum is a well bioenergy crop due to rich fermentable juice and digestible bagasse for high-yield bioethanol production. The aim of this study was to determine the bioethanol capacity of some sweet sorghum ( Sorghum saccharatum) ) genotypes, bioenergy parameters and their interactions under semi-arid climatic conditions. The trial was designed in accordance with a randomised complete block design with four replications in 2016 and 2017 under the Harran Plain (36 degrees 54' 11.82"N and 38 degrees 55' 08.66"E) conditions of the second crop, Sanliurfa, Turkey. A total of 21 genotypes of sweet sorghum were employed in the study. The genotypes were found to be statistically significant in terms of the traits that were tested (p <= 0.01). p <= 0.01 ). The mean of the two-year yield data revealed a range of stalk yield from 9648.4 to 20105.7 kg ha(-1). The Brix values exhibited a range between 12.88% and 19.06%. The juice yield values ranged from 7475.4 to 4085.7 L da(-1), while the sugar yield values ranged from 613.4 to 1128.4 kg da(-1). The ethanol yield values were found between 326.0 and 600.8 L da(-1). The genotypes UNL-Hybrid-3, Topper 76, Nebraska Sugar, Smith, Theis, M81-E and Grass 1 exhibited the highest stalk, juice, brix, sugar and ethanol yield values and were identified as the optimal candidates for ethanol production. A positive and significant correlation was observed at the high level between ethanol yield and sugar yield, syrup yield, stalk yield, juice yield and brix. It is important to consider high stalk and sap yield, high sugar yield and high brix value as selection criteria in the selection of genotypes in breeding programs for a high yield of bioethanol.