Figure 7.

Total PME activities in the micropylar megagametophyte (A), chalazal megagametophyte (B), radicle (C), and cotyledons (D), following incubation of isolated megagametophytes and embryos in water, ABA, or GA₃. Megagametophytes and embryos were excised from mature dormant seeds (subjected to only a 3-d soak) and then placed on water, 0.1 mm ABA, or 0.5 mm GA₃ for 2 weeks. PME activities were monitored by activity assays every 2 d, and the incubation solutions (water, ABA, and GA₃) were changed every 3 d.