Gene action and combining abitiy in line X tester population of safflower (Carthamus tinctorius L.)

Abstract

This research, having F1 hybrids from 6 female lines and 4 male testers, was conducted in order to design to assess the combining ability, to determine the nature and magnitude of gene action, hybrid vigor for yield and related traits and to detect the appropriate crosses for breeding program in safflower. Parents used in the study were developed at the Transitional Zone Agricultural Research Institute (TZARI). In the first year of this research, lines and testers were crossed in all the possible combinations using line x tester mating design. The hybrid population was evaluated in a replicated field trial in Eskisehir, Turkey. According to the results, the specific combining ability (SCA) effects were determined higher than general combining ability effects (GCA) in terms of traits studied. As a result, low ratios of σ2GCA/ σ2SCA, (σ2D/ σ2A)1/2 implied that non-additive effects controlled the traits studied. Existing non-additive gene action in the population, the selection in the advanced generations like F4 or F5 might be effective for improving the high seed and oil yield safflower genotypes.