Widespread interest in Sweet Sudan has been aroused among California growers of Sudan grass. This variety was developed by Dr. B. E. Karper and Dr. J. B. Quinby of the Texas Agricultural Experiment Station from a cross between Leoti, a sweet sorghum, and Common Sudan grass followed by backcrosses to Sudan.

Among plant colors in sorghum the genes for dominant red and recessive black have been designated Qq and have been reported linked with those for subcoat, Bb, and green-striped, Gs gs. A red which is recessive to black was found to have the same association with subcoat and green-striped and it is suggested that the allele be designated qr. The dominant red-glumed varieties used in the crosses were largely of Asiatic origin, while the black and recessive red-glumed varieties were largely of African origin. The contradictory results in which Vinall and Cron reported the red glumes of Red amber sorgo dominant to black glumes whereas they were found to be recessive to black in these segregating populations are explained on the assumption that the strain used by Vinall and Cron had been selected from a broomcorn hybrid.