Applications of some anatomical features of Sida acuta, Tithonia diversifolia and Vernonia amygdalina

Sida acuta, Tithonia diversifolia and Vernonia amygdalina were anatomically studied with the aim of using the features of their anatomy as indices of taxonomic delimitation, raw materials for pulp and paper production and efficient competition and invasiveness. Features such as anomocytic stomata, conjoint, bicollateral and open vascular bundles, glandular and non-glandular trichomes, and sparsely distributed calcium oxalates delimited T. diversifolia and V. amygdalina from S. acuta. S. acuta possessed heterogenous stomatal types, concentric and amphicribal vascular bundles, and stellate and unicellular trichomes. Also, other features like stomatal and trichome density, index and size, and leaf veination delimited T. diversifolia and V. amygdalina from each other. The anatomical features that encourage invasiveness in the plants include, possession of conjoint, collateral and open vascular bundles and short vessel length, moderate stomatal size of 57.56μm on the adaxial surface, low stomatal index of 9.93% and 17.19% on the adaxial and abaxial leaf surfaces, respectively, in T. diversifolia. V. amygdalina possessed low stomatal index of 1.12%, low stomatal density of 23.71mm² also on the adaxial surface and trichomes. S. acuta possessed stomata with a small number of subsidiary cells, small stomata, concentric and amphicribal vascular bundles, higher frequency of stellate and unicellular trichomes. Possession of the appropriate fibre length, fibre diameter, large lumen width, thin cell wall, Runkel ratio of less than 1 and relative fibre length are important dimensional characteristics of the studied species as raw materials for pulp and paper making.