Figure 4
From: Laguncularia racemosa leaves indicate the presence of potentially toxic elements in mangroves
Light microscopy anatomical analysis of Laguncularia racemosa leaves collected in different mangroves in Rio de Janeiro (Brazil). (A,B) Frontal view of epidermis showing ordinary epidermal cells, stomata, unicellular non-glandular trichome (tt), and secretory cavity (cv) after removal of mesophyll with a salt secretory trichome at the bottom (*). (C) Cross section showing cavity (cv) on the abaxial epidermal surface where the salt secretory trichome (*) is located, with opening to external environment (black arrowhead), palisade parenchyma (pp) and spongy parenchyma (sp). (D) Leaf from Coroa Grande (CG): (pp) and (sp), crystal idioblasts with druses (black arrowheads). (E) Leaf from Pedra de Guaratiba (PG): adaxial secretory cavity (cv) with pore (black arrowheads). (F) Leaf from Marambaia (M): (pp), (sp), vascular bundles (vb); black arrowheads point to mucilage in spongy parenchyma. (G) Midvein cross section showing cortical and medullary parenchyma storing phenolic compounds (*). (H) Main vascular bundle evidencing phenolic idioblasts and mucilage (black arrowheads). (I) Cross section taken from a plant growing in M and exposed to Zincon. (J) Cross section taken from a plant growing in CG and exposed to Zincon, evidencing Zn in fibers and idioblasts with druse crystals. (A,E) CG mangrove; (B,F,H) M mangrove and (D,G) PG mangrove. A,B = 500 μm, C, G= 20 μm, D, E, F, H, J= 100 μm, I= 50 μm.
