Fig. 1

Morphology in SAM-less rpk1 monocot seedlings. a Magnifications of parts of monocot rpk1-7 seedlings (gl1/gl1 background) with SAM and primary leaves (top) and without SAM (bottom). b and c Whole plants with long roots (indicated by arrowheads) illustrate the continuous root growth. d A shoot-less monocot seedling from long-term cultivation shows a necrotic cotyledon while the root has continued growth and turned green. e A SAM-less monocot seedling with a homozygous rpk1-7 GL1 background (carrying a PIN1:GFP reporter). f Seedlings cleared with Hoyers mount visualize the vascular system in the contiguous hypocotyl-cotyledon structure with interruptions (white arrowheads) and supernumerary and/or blindly terminating vascular elements (small arrows). There is no bend recognizable, which in the wild-type separates apically the SAM/epicotyl from the laterally placed cotyledon. g A SAM-less monocot seedling originating from the rpk1-6 allele. Cotyledons (c), normal leaf (lf) indicated. Scale bars: 1 mm a-e, 0.5 mm g, 100 μM f