Gene effect, combining ability and heterosis in sunflower morphophysiological traits

Abstract

Four interspecies populations, originating from three annual (H. debilis, H. praecox, H. deserticola) and one perennial (H. resinosus) wild species, were used to produce 13 new (cms) inbred lines with cytoplasmic male sterility, three Rf restorer lines with good general combining ability used as testers and their F1 hybrids. A two-year trial with three replicates was set up using the line × tester method. The inbred A-lines, Rf-testers and F1 hybrids differed significantly in the mean values for both studied traits. The mode of inheritance for leaf area was dominance and superdominance of the better parent and for plant height it was superdominance of the better parent. Highly significant positive values of general combining ability for both traits were found in inbred lines NS-G-7, NS-G-8, NS-G-9. The greatest highly significant positive specific combining ability value was found in NS-G-6 × RUS-Rf-OL-168 for the total leaf area per plant and in NS-G-6 × RHA-N-49 for plant height. The non-additive gene effect had greater influence on both traits. A significant heterotic effect was found for both traits in relation to the parental average so as in relation to the better parent.