Assessment of agronomic performances and ethanol potential in diverse sweet sorghum (Sorghum bicolor L.) cultivars under rainfed conditions

Abstract

Sweet sorghum has shown great potential as an alternative and promising bioenergy crop that has high potential for bioethanol production due to its high sugar yield, wide adaptability and drought tolerance, thus it is important to continuously evaluate and select most promising lines. Therefore, this study aimed to assess the agronomic performance, cane yield, and ethanol potential of local and exotic sweet sorghum cultivars under rainfed conditions. The experimental design was a randomized complete block design (RCBD) with three replications. Ten various sweet sorghum cultivars were utilized as treatments viz. Theis, Cowley, SSV74, SSV84, BJ248, Suwan sweet extra, Suwan sweet1 and 2, Suphanburi1 and KKU40 (check variety). The results indicated that several cultivars have noteworthy performances, exhibiting higher total soluble solids, such as cv. Suwan sweet extra, KKU40, Suwan sweet2, and Theis, as well as higher cane yield, including Cowley, SSV84, and Suwan sweet extra. Additionally, superior juice yield was observed in cv. SSV84, Suwan sweet1, Suwan sweet extra and Cowley, while higher theoretical ethanol yields were observed in cv. Suwan sweet extra, KKU40, SSV84, and Suwan sweet2. The consideration of grain yield revealed notable performances in cv. SSV84 and Cowley. Conclusively, both cv. SSV84 and Suwan sweet extra exhibited higher cane (46.72 and 44.03 t ha-1, respectively) and ethanol yields (958.1 and 1155.7 l ha-1) in alignment with the objectives of this study. Noteworthy traits were also identified in KKU40, Cowley, and Suwan sweet2. The findings from this study offer valuable insights for future research in this field, particularly in enhancing varietal performance in specific environments and promoting adaptability across diverse conditions.