Heterosis in Sunflower( Helianthus annus L.)

Heterosis for yield and its components was studied in 28 hybrids derived from crossing eleven varieties (four varieties used as females and seven viirieties used as males). An appreciable amount of heterosis was observed for almost all the chiirdcters studied. The hybrid, 270A x Modern recorded the highest heterosis over better parent (59.25%) for yield Jier plant which was follqwed by 290 A x RHA-265 (55.15%). The latter cross also shewed good amount heterobeltiosis for the characters like total number of seeds per head and diameter of head. The increased heterosis for yield per plant was parallel with the increase in heterosis for diameter of the head iind total number of seeds per head.