Cross sections of non-adventitious non-flooded roots (A,C) and flooded adventitious roots (B,D) showing reduced size of vascular bundles and poorly-developed endodermis in the adventitious root. The sections were taken at 0–0.2 cm from the root tip (A,B) and 1 cm from the root tip (C,D). The root sections were stained with Sudan IV (A,B) and berberine (C,D). The sections for Sudan IV were mounted on slides and examined under the light microscope. The sections for berberine were examined under the fluorescence microscope (Leica DMRXA Upright Microscope) with a green light filter I3 at 450–490 nm excitation and 510 nm emission. Epidermis (EP), Endodermis (EN) and xylem (XYL) structures are indicated with arrows.