Fig. 1. Steroid-inducible stamen and carpel development. (A,B) ag-3, AGGR inflorescences, mock treated (A) or treated with dexamethasone (DEX; B). (C,D) Close-up view of flowers from the plants shown in A,B; while the mock-treated plant shows an indeterminate number of sepals and petals (C), DEX treatment has induced stamen (st) and carpel (ca) development (D). (E,F) cal-1, ap1-1, AGGR inflorescences, two weeks after mock treatment (E) or treatment with DEX (F). Note the mass of meristems in E (similar to those shown at high magnification in G) compared with the mature stamens and carpels in F. (G-I) Scanning electron micrographs of cal-1, ap1-1, AGGR inflorescences 1 day (G), 3 days (H) and 7 days (I) after DEX treatment. The arrows in H indicate meristems that are beginning to produce organ primordia; in I, developing stamens (st) and carpels (ca) are morphologically identifiable. Scale bars: 5 mm in A,B; 1 mm in C-F; 100 µm in G-I.