Fig. 2. Scanning electron micrographs. (A-E) Shoot apices of plants grown for 30 days under short days. (F-J) Shoot apices of plants after 7 additional long days. Axils of leaf primordia appear empty before the shift to long days (A). White asterisks indicate shoot apical meristems, crosses lateral shoot meristems that form in the axils of leaves. The oldest flower primordia (f) are labeled in F and H-J. Note that these are much younger in co-2 and ft-2 mutants than in wild type, and that flower-like structures have not yet formed in lfy-12 mutants, although several bracts (b) that surround the shoot apical meristem are apparent. Scale bars: 50 µm (A-E,G,I,J); 100 µm (F,H).