A comparative study was carried out on the parthenogenetic reaction of Helianthus annuus L. lines and hybrids used as initial female material for parthenogenetic induction. It was established that the mean parthenogenetic responsiveness of the hybrids was considerably higher than that of the lines. The mean parthenogenetic responsiveness of the lines used as initial female material (2607 A, 2607 B, 1607 A, 1607 B, 1234 A and 1234 B) was lower than the mean responsiveness of the hybrids (Albena, Viki, Euroflor, Perla and San Luka). Within the investigated lines, no specific genotype reaction with regard to parthenogenetic induction was ascertained; such reaction was observed in the hybrids. The hybrids San Luka and Perla had the relatively highest parthenogenetic responsiveness. The analysis of the results showed that the optimal expression of the par thenogenetic responsiveness of the female genotype depended mainly on the interaction with the pollen source. The pollen source Rf 673 induced on average 3.4 times better parthenogenetic reaction in the hybrids Perla, San Luka and Viki that the line Rf 147. The γ-irradiation influenced the expression of parthenogenetic responsiveness of the female genotype through its effect on the parthenogenesis inducing ability of the pollen source.