Ahlam Salih Eltahir and Bouran Ibrahim AbuEReish
Detailed microscopical studies of the leaf and petiole of Vernonia amygadlina Del. (Asteraceae) which is a Sudanese folkloric medicine were carried out. It had been found that there were anomocytic stomata, the stomatal sizes and indices were larger on the abaxial surface. There were many epidermal hairs of different types; unicellular, multicellular, glandular and nonglandular hairs the heads of the glandular hairs appeared bi-lobed. The mean palisade ratio was found to be four. The scanning electron microscopy of the epidermal surfaces revealed that the amount of wax was large on the adaxial surface whereas the number of stomata was more on the abaxial surface. The vascular bundle region of the leaf was divided into four bundles separated by biserriate rays of parenchyma. The powder of the dry leaves of V. amygdalina was dark green in color with faint smell, calcium oxalate crystals were scattered, small veins appeared in longitudinal views with different types of vessel thickening. The transverse section of the petiole showed that the vascular bundles were arranged in a circle, each vascular bundle was preceded by pericyclic fibers.