Fig. 3. In situ analysis of DEF (A,B) and GLO (C,D) expression in longitudinal sections of def; AFI::DEF (A,B) and glo; AFI::GLO (C,D) flowers. The hybridisation signal is confined to the outermost cell layer in young flowers (A,C) and in older petals (B,D). The sections were stained with calcofluor and the hybridisation signal appears as a purple stain in fluorescent light. Bars,100 µm. Numbers indicate whorls.