Development and Structure of Internal Glands and External Glandular Trichomes in Pogostemon cablin (original) (raw)
Figure 4
Ultrastructural aspects of internal glands in leaves of Pogostemon cablin.
An internal gland at secretory stage shows the unique characteristics (A–G). (A) A mature internal glands has a cytoplasmically dense head cell (HC), a narrow stalk cell (SC) with densely stained lateral cell wall (arrow) and a basal cell (BC). (B) The sub-cuticular space (SCS) contains fibrillar material (arrows) and lipid-like material (L). (C) There are numerous small vacuoles (V), mitochondria (M), abundant rough endoplasmic reticulum (RER) and many plastids (P) in the head cell. (D) The plastids (P) are observed to be in close to RER (arrow). (E) And the RER (arrow) is also close to the plasma membrane (PM). (F) The details of the stalk cell show the big nucleus (N), the plump chloroplast (C) and numerous mitochondria (M). (G) A part of transverse wall between stalk cell and head cell is penetrated by numerous plasmodesmata (arrows). (H–J) The ultrastructural aspects of internal glands at late-secretory stage are observed as follows. (H) The sub-cuticular space is filled with numerous lipid spherosomes (*). (I) Plastids (P) contain numerous oil droplets (arrows). (J) Lipid droplets (L) in sub-cuticular space are surrounded by silk-like structure (arrows).