Abstract
Fourteen cytoplasmic male sterile lines and 6 testers were crossed in a line x tester fashion to develop 84 sunflower hybrids during Spring, 2000 at Oilseeds Research Institute, AARI, Faisalabad, Pakistan. The hybrids and parents were evaluated during Spring 2001. Highly significant differences existed among genotypes for all the studied plant traits. The highest heterosis and heterobeltiosis for stem girth was showed by crosses ORI-3 x RL77 and ORI-3 x RL-84, respectively in the positive direction. The cross combination ORI-3 x RL-84 exhibited maximum increase over mid and better parents for 100-achene weight. The highest positive heterosis and heterobeltiosis for oil content was exhibited by crosses ORI-6 x RL-27 and ORI-47 x RL-69, respectively. Crosses ORI-29 x RL-84 and ORI-3 x RL-77 showed the maximum increase over mid and better parents, respectively for head diameter. The hybrid ORI-20 x RL-77 showed highest positive heterosis and heterobeltiosis values for plant height. The cross ORI-3 x RL-77 showed the highest positive heterosis over mid and better parents for both number of seeds per head and oil yield. Key words: Sunflower, Heterosis, Heterobeltiosis, Stem girth, Head diameter, Plant height, Seed yield
