Rhizome expression in a selected cross in the Sorghum genus

The segregating F₂ population from the hybrid between grain sorghum (Sorghum bicolor), chromosome number doubled, and Johnsongrass (S. halepense) was examined for expression of rhizomes. A rhizome to non-rhizome segregation ratio of 3:1 was observed suggesting a single dominant gene regulation in the rhizome phenotype of S. bicolor and S. halepense. Approximately 72% of the F₂ population overwintered and regrew from the rhizomes the following spring. When comparing these data with data in the literature, the rhizome regulating gene in the Sorghum genus may be an incomplete dominant gene requiring a few genes to be expressed additively that result in different degrees of rhizome development in the Sorghum genus. This revised version was published online in July 2006 with corrections to the Cover Date.