Floral Nectary Anatomy and Ultrastructure in Mycoheterotrophic Plant, Epipogium aphyllum Sw. (Orchidaceae)

Figure 6

Lip spur: (a) adaxial (inner) surface of spur with places of secretion (yellow) at the apex of the spur, the 6th day of anthesis (SEM). (b) Places of secretion inside spur, 4th day (SEM). (c) Secretion on the adaxial surface of spur, 2nd day (TBO). (d) Secretion on the adaxial surface of spur stained for proteins; notice large nuclei, 2nd day (ABB). (e) Secretion inside spur stained for polysaccharides insoluble in water, starch grains visible in cells, 5th day (PAS). (f) Secretion on the adaxial surface of spur, stained for lipids (SBB). (g-h) Secretion on the adaxial surface of spur (TEM) (cw: cell wall; se: secretion).