Fig. 6. Hb is required for floral asymmetry. (A) The wild-type corolla contains two dorsal petal lobes (d), two lateral lobes (l) and one ventral lobe (v) shown here detached from the corolla tube with their dorsal surfaces uppermost. Each type of petal lobe has a characteristically asymmetric shape and distribution of pigment. The corresponding petal lobes of hb single mutants show reduced asymmetry in both shape (stars) and pigmentation (arrows). (B) In the wild-type corolla tube (viewed from below), the ventral petal is characterised by a bulge in its proximal region and two stripes of pale pigmentation mark its boundaries with lateral petal. In hb single mutants, the bulge extends laterally. Reduced activity of Cyc or Rad genes has a similar effect (data not shown).
