Figure 4.

Comparison of Wild-Type and bop1 bop2 Floral Phenotypes.

(A) Morphology of mature flowers. (a) Wild type. (b) bop1. (c) bop2. (d) bop1 bop2 abaxial side. (e) Adaxial side. (f) Abaxial view of a flower with abaxial first whorl organs removed. (g) Abaxial view of a young flower showing retarded growth of abaxial organs in the first whorl. (h) Example of fused abaxial first whorl organs with sepal-petal characteristics. Bars = 1 mm. (i) to (k) Examples of bracts and bract-like structures that subtend flowers. Bar = 0.5 mm.

(B) Scanning electron micrographs of wild-type and bop1 bop2 inflorescence apices depicting inflorescence meristems, floral meristems, and flowers. (a) Wild-type inflorescence apex. The asterisk marks the abaxial sepal. (b) bop1 bop2 inflorescence apex. Arrows indicate floral bracts. (c) Stage 2 floral primordia with subtending bract (arrow). FM, floral meristem. (d) Stage 5 flower with subtending bract and five evenly spaced organs in the sepal whorl such that the adaxial sepal is in the same position as in the wild type. An extra stamen primordia occurs between the two abaxial sepal whorl organs (asterisks). (e) Stage 7 flower showing retarded development of sepals. Smaller abaxial first whorl organs are marked by asterisks. (f) Example of a flower with abaxial first whorl organs that are half-sepal (bumpy cells) and half-petal (smooth inner cells). Bars = 50 μm except 100 μm in (e) and 500 μm in (f).

(C) Floral diagrams for wild-type and bop1 bop2 flowers. The adaxial side is marked with a closed circle and indicates the position of the stem. The wild-type flower shows radial symmetry (left), and the bop1 bop2 flower shows bilateral symmetry (right).