Mature leaf of Dimerostemma vestitum. (A) leaf mesophyll evidencing the palisade parenchyma (Pp), spongy parenchyma (Sp) and a cuticle layer (Cu) on the external periclinal wall of epidermal cells (Ep); (B) leaf vein, showing the mesophyll (Me) partly entering in the main vein and vascular bundles (*) surrounded by cortex with lignified cell walls and parenchyma cells in lignification process (Co). (C) Detail of the secretory canals associated with the vascular bundle in the central vein (arrow). (D-J) Scanning electron microscopy of the leaf. (D-F) Adaxial epidermis showing trichomes, non-glandular (Tt) and glandular (Gt), and stomata (arrow heads) in depressions at the epidermis; (GJ) Abaxial epidermis showing the presence of non-glandular trichomes (Tt) on main leaf vein (Lv), glandular trichomes (Gt) and stomata (arrow head) above the level of other epidermal cells. (K-L) Histochemical analysis of the leaf. Phenolic compounds in non-glandular trichomes evidenced by ferric chloride (K); glandular trichome evidencing the presence of lipophilic substances by the Sudam IV reagent (L). Scale bars: 100 µm (A, J, K, L); 500 µm (B); 60 µm (C); 20 µm (D, E); 10 µm (F); 200 µm (G); 5 µm (H); 160 µm (I).
Aerial stem of Dimerostemma vestitum. (A, B) Transversal sections of the apical portion (A) highlighting cell wall thickening in the medullar region (M), vascular cylinder (Vc) and cortex (Co). Details of the collateral vascular bundle (B) with primary xylem (Px), phloem (Ph) and sclerenchyma bundles (Sb); (C, D) Basal portion of the aerial stem. General view (C) highlighting medullar parenchyma (Mp), radially arranged cells (Rp), vascular cylinder (Vc) and cortex (Co). Detail of the vascular cylinder (D) showing the formation of the vascular cambium and xylem (X), phloem (Ph) and sclerencyma bundle (Sb). (E) Detail of angular collenchyma (Ac) layers beneath the epidermis, isolated sclereids (S), sclerenchyma bundles (Sb) and secretory canal (circle); (F) Formation of a secretory canal (circle) and evidence of endodermis with Casparian strips (arrow) and sclerencyma bundles (Sb). (G) Stem in the basal portion, showing detail of the vascular cylinder, cortical (Co) and medullar region (Rp, Mp). (H) Distinction of the medullar parenchyma (Mp) in a central region and another peripheral, with radially arranged cells (Rp). Scale bars: 1000 µm (A, C); 100 µm (B, E, F); 200 µm (D); 500 µm (G, H).
Underground organs of Dimerostemma vestitum indicating the analyzed portions (A): Soil level (S); Proximal region (1); Median region (2); Distal region (3); Lateral root (4). Longitudinal sections of the buds of the xylopodium of D. vestitum stained with toluidine blue (B). Arrow heads indicate the vascular cambium; cataphyll (C); bud (B); periderm (Pe). (C-H) Transversal sections of the xylopodium. (C-D) Proximal region, detailing the centrifugal maturation (circle) of primary xylem (D). (E-F) Median region of xylopodium showing the formation of periderm, secondary xylem rays and vascular cambium (arrow). (G-H) Distal region of the xylopodium showing (G) periderm (Pe), secretory canals (*) and fibers associated to phloem (Sb). (H) Growth layers (arrow heads) of secondary xylem (X), xylem parenchyma (Xp) and phloem (Ph). Scale bars: 1cm (A); 1000 µm (B, E); 3000 µm (C, H); 500 µm (D, F, G).
Transversal (A-D) and longitudinal sections (E, F) of the distal portion of the xylopodium of Dimerostemma vestitum. (A) Overview of xylopodium showing positive reaction of fructans to PAS reagent (arrow head); (B) Detail of fructans accumulated in the xylem parenchyma cells (Xp) and vessel elements (arrow head); (C, D) Details of inulin accumulation (arrow heads) inside vessel elements (C) and in the parenchyma cells (D); (E, F) Inulin sphero-crystals viewed under polarized light (arrow heads) in parenchyma cells; (G, H) Scanning electron microscopy of inulin particles (arrow heads) accumulated in the parenchyma cells (G) and in vessel elements (H). Sclereids (S). Scale bars: 1000 µm (A); 100 µm (B, C, D); 250 µm (E, F); 10 µm (G); 5 µm (H).
HPAEC/PAD profiles of soluble neutral carbohydrates of vegetative aerial and underground organs of Dimerostemma vestitum. Oligosaccharide (A, C, E, G, I) and polysaccharide (B, D, F, H, J) fractions of leaves (A, B); Stem (C, D); Lateral roots (E, F); Xylopodium: Peripheral (G, H) and central (I, J) regions.Fructose (F);Glucose (G);Sucrose (S); 1-Kestose (1K); Nystose (N); Arrows indicate the increase in degree of polimerization (DP).