Figure 3

Confocal imaging of wall ingrowth deposition in CC TCs of leaf minor veins in pea. A. Minor veins from second true leaf of 13 day-old full light-grown seedlings showing mottled wall ingrowth labelling across the full face of CC TCs (asterisks). No wall ingrowth deposition is seen in PP cells. A y-z projection of a z-stack through the vertical minor vein is shown in inset A’. Wall ingrowth deposition detected as fuzzy labelling can be seen along all longitudinal walls of the CC TC (asterisk). A y-z projection through the horizontal minor vein at the bottom right of A is shown in inset A”. Here, fuzzy labelling indicating wall ingrowth deposition is seen around all faces of the CC TCs seen in transverse view. The double asterisk in A and A” indicates a large CC TC. B. Minor veins from second true leaf of 9 day-old seedling subjected to 4 days of darkness. No wall ingrowth deposition is seen in CC TCs (asterisks) seen in B or when the minor vein is seen in transverse view as a y-z projection through this minor vein (inset B’). BS, bundle sheath cell; PP, phloem parenchyma; SE, sieve element; XE, xylem element. Scale bars = 10 μm in A, A’ and B. Scale bars = 5 μm in A” and B’.