*2.6. Anatomical Observations*

Anatomical studies were conducted using the middle-third section of the second completely developed leaf. Leaf cross-sections were obtained by freehand sectioning using a steel blade, fixed in 70% FAA (formaldehyde-acetic acid-ethyl alcohol 70%) for 48 h, and then preserved in ethanol 70% (*v*/*v*). Following discoloration in sodium hypochlorite (1–1.25% active chlorine), triple-rinsing in distilled water, and staining in toluidine blue (0.05% *w*/*v*), leaf sections were subsequently fixed on semi-permanent slides with glycerinated water [25]. The slides were examined and photographed under the same light Leica DMLB microscope and the SPOT 4.7 idea digital camera and software, as described earlier. The images were evaluated by assessing five fields per repetition for each variable analyzed. The thickness of the abaxial surface epidermis (ASE), adaxial epidermis (ABE), abaxial hypodermis (AH), adaxial hypodermis (AbH), palisade parenchyma (PP), and spongy parenchyma (SP) were determined. Five random plants were selected per treatment.
