Description

ABSTRACT

African bush mangoes (Irvingiaceae) are important food trees local to the west and central Africa. There are seven species in this family and two have been distinguished as the bitter and sweet fruited trees (Irvingia gabonensis and Irvingia wombolu). These trees are difficult to distinguish based on morphological characters alone, hence, in this study, the leaf epidermal attributes as well as the quantitative composition of selected phytochemicals of the seeds were studied and compared with the aim of providing extra taxonomic characters for the classification of the species. Results obtained revealed significant differences in the epidermal layer of the studied species. Differences were observed in the number, length, and width of the epidermal and stomata cells, the shapes and wall of the epidermal cells varied significantly on the adaxial surface, while that of Irvingia gabonensis was polygonal and straight, that of Irvingia wombolu was irregular and curved. Both species possessed the following similarities on the epidermal layer: irregular and curved epidermal cells on the abaxial, hypostomatic (possession of stomata only on the abaxial) and paracytic stomata types. The phytochemical composition varied as well, while there was no significant difference in the quantity of alkaloid, flavonoid, tannins and phenols, the quantity of saponin and sterol varied significantly with Irvingia gabonensis having 0.80±0.01 and 0.21±0.02 and Irvingia wombolu having 0.73±0.00 and 0.15±0.01 respectively. The differences observed were significant therefore supporting the idea that the two plants are of different species and should be accorded different taxonomic classifications.

Keywords: Epidermal, Phytochemicals, Stomata, Seeds, Taxonomic and Abaxial