Response to selection in the initial stages of a perennial sorghum breeding program
Abstract: 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 overall 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.