Chemical, physical and morphological properties of diploid and tetraploid Sorghum bicolor (L.) Moench kernels

Grain produced on diploid (2X) and tetraploid (4X) lines of the sorghum, Sorghum bicolor (L.) Moench, cultivar, Tx 403, was compared for physical, morphological, and chemical properties. Grain from tetraploids was greater in kernel size and protein content and was lower in starch content and test weight than grain from the diploid. Mean values of diploids and tetraploids were 12.8 and 15.7% protein, 72.3 and 68.8% starch, 26.8 and 41.4% g/1,000 kernels, and 74.3 and 70.0 kg/hi respectively. Grain from the tetraploid contained 3.3% less endosperm and a slightly higher proportion of bran than grain from the diploid. The relative proportion of germ was the same. Endosperm cells of the tetraploid were larger than those of the diploid. Kernel density and amino acid composition were similar. Low seed set of the tetraploid plants may partially explain the increase in protein and other differences