Fig. 3. Phenotype of mutants showing defects in fertilization and embryo development. (A) Silique showing a wild-type (Wt) and one mutant embryo (Mt) sac, both with pollen tubes (Pt) at the micropyle (UNE 10). (B) Silique showing two wild-type embryo sacs with pollen tubes at their micropyles and one mutant embryo sac that failed to attract a pollen tube to its micropyle (UNE 14). (C) Mutant embryo sac presenting two intact synergids after pollination (UNE 9). (D) Mutant showing embryo development arrested at the one-cell stage presenting two big endosperm nuclei (End n) (MEE 31). A single arrow indicates the zygote. (E) Mutant showing an abnormal embryo proper (Ep) and suspensor (MEE 70). (F) Wild-type control embryo at early heart stage. Scale bar: 25 µm. Syn, synergide; Ec, egg cell; Ccn, central cell nucleus; F, filament.