Genetic implications in transferring fertility restorer genes to a new genetic background in sunflower (Helianthus annuus L.)

The second generation progeny consisting of seven surviving plants of the cross between the male sterile hybrid, 2 cm 183 x E.C. 68415 and the restorer line, BCZ. 111 presented two types of segregation for the pollen fertile and sterile plants. Four of them gave a 3:1 ratio for the fertile and sterile fractions while the remaining three progenies fitted into a 9:7 ratio, thus suggesting two genotypes in the F sub(1) plants from the point of fertility restoration. The implications underlying this type of inheritance have been discussed and the genetic symbols of rf sub(1)rf sub(1)rf sub(2)rf sub(2), Rf sub(1)Rf sub(1)rf sub(2)rf sub(2) or rf sub(1)rf sub(1)Rf sub(2)Rf sub(2) and Rf sub(1)Rf sub(1)Rf sub(2)Rf sub(2) have been suggested for the parents 2 cm 183, E.C. 68415 and BCZ. 111 respectively.