Association Between Stem and Agronomic Traits to Juice Yield in Sorghum.

In the past few years production of sorghum-based ethanol has transitioned from conceptual to industrial scale in Brazil. The crop plays a key role as a complement to existing feedstock supplies needed in sugarcane mills, allowing the extension of their operating season.  To support this emerging industry, breeding and agronomic research is essential to increase productivity and efficiency. Generally, qualitative methods to estimate sugar yield in sweet sorghum hybrids are derived from sugarcane.  Within that context, the major objectives of this study were to determine the role of various stalk and agronomic traits with juice yield and to verify their repeatability.  A diverse sorghum panel composed of 20 grain sorghum and energy genotypes were grown in two Texas environments.  Repeatability estimates for flowering, total fresh biomass, stem diameter, stalk volume and pithiness were moderate to high (>0.50) and correlations between them ranged from +0.98 to +0.58. Our results indicate that some major agronomic and stem-related traits could be used as indirect selection targets to improve extractable sugar yield.