THE GENETICS OF FERTILITY RESTORATION IN CYTOPLASMIC MALE-STERILE RYE

Abstract

Three inbred lines of rye (Secale cereale L.) known to be capable of restoring fertility to a cytoplasmic male-sterile line were crossed with the sterile line. The proportions of male fertile, partially male fertile and male sterile plants in F₂ and backcross progenies indicated that three dominant restorer genes were present in each line. These were designated Rf₁, Rf₂ and Rf₃, their relative expressivity was Rf₁>Rf₂>Rf₃. Expressivity was dependent upon environment. Partial fertility occurred when certain genotypes carried two of the three alleles as dominant, but was dependent upon genotype and environment.