Studies were carried out to estimate the extent of heritability in some cultivated genotypes of sweet sorghum (Sorghum bicolor L. Moench). Thirty genotypes were used for the evaluation. The phenotypic coefficient of variation (PCV) was greater than the genotypic coefficient of variation (GCV) for most traits studied. Days to 50% flowering (DTF) had low PCV and GCV. Head weight had low GCV but higher PCV. 1000 grain weight was also low for PCV and GCV. Moderate GCV was observed within the range of 11.7 (stem thickness) to 19.8 (number of nodes). High GCV was observed within the range of 22.3 (panicle length) to 31.5 (sugar content). Moderate PCV ranged from 13.3 (stem thickness) to 16.6 (number of nodes) and PCV ranged from 20.0 (number of nodes) to 43.3 (head weight). But the GCV was near to PCV for traits like DTF, plant height, number of nodes, number of leaves, grain yield and sugar content, indicating a highly significant effect of genotype on phenotypic expression for these traits with very little effect of environment. The genotypes studied showed high heritability for eight (8) traits out of the 10 traits studied in the range of 69.4 (plant height) to 97.3 (number of nodes). Moderate heritability of 55.9 was observed for 1000 grain weight and low heritability of 1.5 for head weight. Keywords: heritability, GCV, PCV, genotypes
