Fig. 1. Kernel phenotypes of semaphore1 mutants. (A) Portion of a self-pollinated ear from a sem1-R/Sem1 heterozygous plant, segregating for approximately one in four mutant kernels (arrow). (B) Mutant kernels (lower tier) contain both a smaller embryo (em) and endosperm (en) than non-mutant sibling kernels (upper tier). (C) Non-discordant kernels are generated following pollination of sem1-R/Sem1 heterozygous plants by plants harboring the B/A translocation TB-9Sd. The kernel on the left contains a hypoploid, mutant endosperm (genotype sem1-R/sem1-R/–) and a purple, hyperploid non-mutant embryo (genotype sem1-R/Sem1/Sem1). The sibling kernel on the right contains a hyperploid, purple non-mutant endosperm (genotype sem1-R/sem1-R/Sem1/Sem1) and a hypoploid, mutant embryo (genotype sem1-R–).