Figure 5. Pl′ Establishment in an rmr1 Mutant Background.

Plants with a T6–9 translocation chromosome carrying Pl1-Rhoades in the Pl-Rh state (dark anther pigmentation) and heterozygous for the rmr1–2 allele were crossed to Pl′ plants (light anther pigmentation) heterozygous for the rmr1–1 allele. Of the resultant progeny with semi-sterile pollen (heterozygous for the T6–9 interchange pair), plants homozygous for a mutation at rmr1 were chosen based on the dark anther phenotype. These plants were then crossed to a Pl-Rh tester with the expectation that in progeny inheriting the interchange, the expression status of the Pl1-Rhoades allele on the T6–9 translocation chromosome (T6–9 Pl(?)) would indicate if establishment of the Pl′ state was affected in the F1. The numbers represent the number of plants displaying a given anther phenotype, indicating that the Pl′ state was established on the interchange chromosome in the rmr1 mutants.