A phenetical (morphological characters) and histological investigations were
carried out as taxonomic evidences for representing, in general, the relationship
between different taxa of genus Datura, namely; D.mete/, D.ferox, D.tatu/a and
D.stramonium, and specially between last two taxa for the taxonomic arguments
raised between them. All the morphological and histological results suggested that D.mete/ is a
distinct species characterized by a unique characters; e.g., flower large, fruit spherical,
fruit suture of densely hairs, fruit rachis is curved downward. These characters are
varied when compared with those of other taxa. D.ferox came in the middle category
in its characteristics between D.mete/ from one side and D.tatu/a and D.stramonium
from the other side. D.ferox sharing D.mete/ in green purple colour stem and white
center strip of hilum. While, D.ferox sharing D. tatu/a and D.stramonium the ovate fruit
shape, erect fruit rachis, seed size and brown or beige seed colour. D.tatu/a and D.stramonium were more similar to each other in many
morphological and anatomical characters than to any of the other studied taxa and
could be classify under white stramonium for D.stramonium and purple stramonium for
D. tatula. Some of these characters are; flower size, moderately spines on fruit
surface, erect fruit rachis, fruit shape, root cortex thickness, root vascular cylinder
thickness, stem cortex thickness and barrel stem epidermal cell.