Economic heterosis in sunflower (Helianthus annuus L.): Seed yield and yield attributing traits in newly developed hybrids

Present investigation was carried out to spot out the best parent combinations giving high degree of useful heterosis for economic traits like seed yield and other yield attributing characters for sunflower breeding programme. Economic/Standard heterosis is the measure of heterosis in terms of superiority over the standard check(s)/hybrid(s). The degree of heterosis varied for important useful characters among different crosses. Presence of high heterosis in certain crosses and low in others suggested that the nature of gene action varied with genetic architecture of the parents. For seed yield (kg/ha),the range of significant heterosis was observed from -21.4 per cent (CMS-10A XR6D-1) to +19.0 per cent (P-2-7-1A X R 601958) along with two hybrids namely P-2-7-1A X R 601958 (19.0%) and CMS-10 A X R-104 (12.4%) over standard check LSFH-171. The range of economic heterosis over DRSH-1 was recorded from -7.8 per cent (CMS-10A XR-6D-1) to 39.6 per cent (P-2-7-1A X EC-601958) with a total of twelve hybrids registering significant positive heterosis over DRSH-1. Among them, P-2-7-1A X EC-601958958(39.6%), CMS-10 A X R-104(31.8)%), P-89-1A XEC-601958(22.4%) and CMS-302A X EC-512682(20.0%) were found to be a superior crosses. For oil yield (kg/ha), significant heterosis was observed from -21.8 per cent (P-89-1A X R-630) to 22.60 per cent (P-2-7-1A X R 601958) along with the five hybrids such as P-2-7-1A X R 601958(22.6%), P-89-1A X EC-601958 (15.9%), P-2-7-1A X R-6D-1(15.6%) and P-89-1A X R-104 (11.3%), over standard check LSFH-171. Whereas, the significant heterosis over DRSH-1was recorded from -19.5 per cent (P-89-1A X R-630) to 26.2 per cent (P-2-7-1A X R 601958). The four crosses such as P-2-7-1A X R 601958 (22.6%, 26.2%), P-89-1A XEC-601958 (15.9%,19.3%), P-2-7-1A X R-6D-1(15.6%, 14.9%) and P-89-1A X R-104 (11.3%,14.6%) recorded the highest significant heterosis over both the checks LSFH-171 and DRSH-1 for the traits namely seed yield and oil content respectively.