Response to selection in the initial stages of a perennial sorghum breeding program

When developed, perennial grain sorghum could provide an opportunity for more ecologically sound food production. In 2002, we initiated a perennial sorghum breeding program, using Sorghum bicolor (L.) Moench × S. halepense (L.) Pers. populations. In 2011–2013, we evaluated 27 breeding lines from three stages of the program in field experiments to estimate response to selection during the program’s first 7 years for perenniality and more domesticated phenotype. Regression analysis of mean grain yield and single-grain weight on breeding cycle (0, 1, 2) indicated a significant increase in each of the seeded experiments and for means over all years. For winter survival index, the regression coefficient was small but significant and negative in 2011, while non-significant in 2012. Grain yield was not significantly correlated with survival index, while single grain weight was significant and negatively correlated with survival index, with r = −0.4923. We conclude that combined selection for perenniality, a more domesticated phenotype, adaptation, greater grain size, and higher grain yield can result in progress in breeding perennial sorghum.