Heterosis for seed, oil yield and quality of some different hybrids sunflower

Twenty-one hybrids of sunflower were produced by crossing 7 introduced cytoplasmic male sterile lines (CMS-lines) with 3 restorer lines (RF-lines) using line × tester mating design. The twenty-one hybrids, three restorers, seven maintainer lines (B-lines) were evaluated. The experiment was conducted in a randomized complete block design of three replications. Mean squares due to genotypes, parents (P), crosses (C), lines (L), testers (T), P vs. C, for stearic acid and line × tester for palmitic acid. The inbred lines and their F 1 hybrids differed significantly in their mean values of the traits under study. The variances due to specific combining ability (SCA) were higher than general combining ability (GCA) variances for all the studied traits, showing non-additive type of gene action controlling the traits. Non-additive type of gene action can be utilized for varietal improvement through heterosis breeding. Heterosis values for seed yield plant −1 were positive and highly significant relative to both the parental mean (17.68–72.38%) and the better parent (−2.86–56.842%). Significantly and negative heterosis was recorded in the case of linoleic acid relative to the parental mean (−81.24 to −38.02%) and better parent (−66.24–22.87%). With oleic acid, the heterotic effect ranged from −14.18 to 39.59% (parental mean) and from −15.06 to 38.72% (better parent). Therefore, these results are valuable for the improvement of quantitative as well as qualitative traits in sunflower breeding material to fulfill the edible oil requirements. Vingt et un hybrides de tournesol ont été produits par croisement de 7 lignées mâles stériles cytoplasmiques (lignées CMS) avec 3 lignées restauratrices (lignées RF) en utilisant un modèle de croisement lignée × testeur. Les 21 hybrides, 3 lignées restauratrices et 7 lignées mainteneuses (lignées B) ont été évalués. L’expérience a été menée selon un plan en blocs complets randomisés avec trois répétitions. Les effets des génotypes, parents (P), croisements (C), lignées (L), testeurs (T), P vs. C et lignée × testeur (L × T) étaient significatifs pour tous les caractères étudiés, à l’exception des parents pour l’acide palmitique, des testeurs pour l’acide stéarique et de l’interaction lignée × testeur pour l’acide palmitique. Les valeurs moyennes des caractères étudiés différaient significativement entre les lignées et leurs hybrides F 1 . L’aptitude spécifique à la combinaison (ASC) était plus importante que l’aptitude générale à l