Genes for pollen fertility restoration in sunflowers

Summary Research on 16 sources of pollen fertility restoration revealed that this character was controlled in eight cases by one single dominant gene, in three cases by two complementary genes, in four cases by three complementary genes and in one case by the cumulative action of two nonallelic dominant genes.The presence of minor genes for restoration in the genotype of the fertile analogue B could effect partial fertility restoration in the cytoplasmic male-sterile line A, especially in late backcrosses, when its genotype becomes saturated with such polygenes.A second major gene Rf ₂ was identified among the investigated monogenic restorer sources.