Mode of inheritance and heritability of disc flower corolla length and nectar content in sunflower

Since disc flower corolla length and nectar content are the two most important parameters of attractiveness to pollinators in sunflower and we monitored them in the parental lines F[ hybrids, we thought it would be interesting to determine the mode of inheritance and heritability of these two traits. The mean values of disc flower corolla length ranged between 7.23-10.22 mm. Differences among most of the genotypes were significant Year had significant influence on the expression of this trait. In the inheritance of the corolla length, partial dominance of the parent with the smaller corolla length (NS-H-702) was observed when determining mode of inheritance relative to the parents. Relative to the parental average however it was not possible to determine the mode of inheritance in any of tile hybrid combinations. The nectar content means ranged from 2.08 to 15.54 mg/20 flowers and differences among most of the genotypes were significant. Partial dominance of the parent with the smaller nectar content mean was recorded in the inheritance of this trait (NS-H-702): Negative heterosis was found in the hybrid NS-H-45