Seedling and meristem phenotypes of Gn1;Xcl1 and Rs1;Xcl1 double mutants. A, Gn1 seedlings have ligular displacement leading to erect leaves 1 and 2 compared to wild-type and Xcl1 seedlings. Gn1;Xcl1 double mutants (at right) have extremely reduced leaves, are agravitropic, and do not initiate lateral roots. B, Rs1 seedlings are similar to Gn1. A less severe double mutant with one leaf is shown at the right. C, Gn1 meristem at the P3 stage is very similar to wild type (Fig. 1A). D, Gn1 meristem dissected to P1/P2 stage. E, Gn1;Xcl1 apex appears much larger than Gn1 and leaves do not encircle the meristem. A delayed leaf with radial tip is also present (arrow). F, Rotated view of meristem in E reveals a bifurcated leaf primordium. G, Dissected Gn1;Xcl1 meristem (same as E) with aberrant phyllotaxy and leaf shape. H, Rs1;Xcl1 meristem with aberrant phyllotaxy and elongated internodes. I, Naked Rs1;Xcl1 meristem that has failed to initiate leaf primordia at regular intervals. Scale bars for all sections = 200 μm.