Heterosis in relation to combining ability in sesame

The performance of 36 hybrids of Sesamum indicum L. involving cultivars of diverse origin was studied to estimate heterosis for seed yield and other component characters. The midparental (MP) and betterparent (BP) heterosis for seedyield ranged from -91.9 to 76.3% and -47.1 to 72.5%, respectively. Out of 36, 19 hybrids showed significant positive heterosis over the corresponding BP for seed yield. Significant heterosis for all the other components (except for plant height and per cent oil), the highest magnitudesbeing from seedyield on secondaries, seed yield on primaries and seed yield on main stem was also observed, indicating their contribution towards seed yield heterosis. Crosses, R 84-4-2 x VS 16 and RT S4 x VS 16, involving high general combining parents, manifested very high and significant heterosis and sea effects for seed yield, and are useful for exploiting hybrid vigour.