Abstract: The relationship between sesame heterosis and combining ability effects for 10 characters of 54 cross combinations were analysed in this paper. The results showed that heterosis of sesame existed generally, and the preponderance of super-dominance was rather high. The magnitude of superiority for characters followed the sequence, seed yield per plant > capsules per plant > length of fruiting section> plant height. But the heterosis for other characters was much lower.Heterosis for all characters was closely positive correlated with its specific combining ability (SCA) effects. The heterosis was mainly supplied by the SCA effects.But some crosses with a small or negative SCA effects could also show-significant heterosis, which mainly comes from their parents’ high heterosis which was included in general combining ability (GCA) effects. Therefore, in the selection of high heterosis combinations,the heterosis effects of parents should not be ignored as well as the SCA effects of crosses.

Key words: Sesame, Hcterosis, Combining ability