Estimation of combining abilities in sunflower (Helianthus annuus L.)

In commercial production, sunflower hybrids are more represented than open pollinated varieties. The basic advantage of hybrids over varieties is that the hybrids allow the use of heterosis. Sunflower hybrids are more stable, highly self-fertile, with high yield performance, and more uniform at maturity in comparison to open pollinated varieties. Also, it is easier to incorporate disease resistance in hybrids, as it was confirmed in the development of hybrids which are genetically resistant to rust, downy mildew, broomrape and some other disease. The heterotic performance of a hybrid combination depends on the combining abilities of its parents. Combining ability analysis is an important tool for the selection of desirable parents as well as for getting the information regarding nature and magnitude of gene effects controlling quantitative traits. The aim of study was to determine general and specific combining ability of 20 newly developed restorer inbred lines resistant to Orobanche cumana Wallr