QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

Help viewing high resolution images Return to article

Fig. 5. Isolation of the site of incipient leaf formation (I₁) from the meristem leads to defects in dorsoventral patterning of the isolated primordium. (A) Leaf primordium of an untreated control apex. Note the difference in trichome morphology on the adaxial side compared with on the abaxial side. Abaxial trichomes are mostly long and linear, with interspersed short linear and globular trichomes. Adaxial trichomes are exclusively globular, and are arranged in a row along the central axis of the primordium. The lateral leaflets (white arrowheads) emerge from the edge between the adaxial and abaxial domain, and point to the meristem (removed for better visibility). (B) Leaf primordium with weak dorsoventral defects. The upper half of the primordium was removed for better visual access. Note the more central position of the second leaflet pair (white arrowheads), and the absence of globular trichomes on the basal portion of the adaxial side (asterisk). (C) Leaf primordium with intermediate dorsoventral defects. The upper half of the primordium was removed for clarity. Note the fused single leaflet in the centre (white arrowhead), and the absence of globular trichomes below the leaflet (asterisk). (D) Leaf primordium with strong dorsoventral defects from the same apex as is shown in Fig. 1B-E. I₁ is completely radialized, except for a small distal portion (between arrows). (E,F) Leaf primordia that lack any sign of dorsoventral patterning. The primordium in E is retarded, whereas the primordium in F grew out to a normal length. Note that the trichomes around the entire circumference of the primordia correspond to abaxial trichomes (compare with A and B). (GJ) Development of an apex after incision through the meristem centre. The meristem continues to grow and to form leaf primordia (H, 1 day; I, 3 days), and finally splits (J). I₁ and the following primordia exhibit normal dorsoventral curvature. P₃, P₂ and P₁ indicate the bases of pre-existing leaf primordia that were removed at the beginning of the experiment; I₁, I₂ and I₃ indicate primordia formed after the operation. Black arrowheads indicate the incision. Scale bar: 100 µm.

Return to article