Fig. 4. Double mutant phenotypes of pin1 cuc1. (A, left and center) 4-day-old seedlings of pin1-3 cuc1 with significant splits at the top (left) and no splits (center) and (right) 6-day-old seedling of pin1-6 cuc1. (B-D) Histological sections of the SAM stained with Toluidine Blue. (B) Wild type. (C) pin1-6. (D) pin1-6 cuc1. Scale bars, 50 µm. (E-G) Confocal images of the apices of mature embryos stained with propidium iodide. (E) Wild type. (F) pin1-3. (G) pin1-3 cuc1. The SAM is the area of small densely stained cells. Note the SAM is smaller in pin1-3 cuc1 embryo. Scale bars, 50 µm.