SOURCE:

Faculty: Biosences
Department: Botany

CONTRIBUTORS:

Muoka R. Ogechukwu
Amadi J. E.
Okeke C.U.

ABSTRACT:

Musa sapientum ( banana) varieties are highly valued tropical plants due to their social, cultural, medicinal, nutritional, ornamental and economic importance but there exists difficulties in their taxonomic classification. The morphological, anatomical, genetical, phytochemical features and mineral constituents of six Nigeria Musa sapientum var.‘Unele Egbeala’, var.‘Unele Mmemme’,var.‘Unele Ojii’, var.‘Unele Ocha’, var.‘Unele Akpukpoike’ and var.‘Unele Obuo odaa’) were randomly collected in triplicates with a view to identify features of taxonomic value using established protocols. The banana plants used were harvested at physiologically matured stages of the fruit.The different parts of the plants were used for the study. Morphological characterizations were carried out by visual observation, metric measurement and photograph. Stained microtome sections were used for anatomical studies. Ethanolic Extracts of ground parts of the plants were used for phytochemical and proximate studies using recognized standard procedures of AOAC. Diluents of the digested powdered samples were used for atomic absorption spectroscopy for determination of the mineral contents. Distal 15mm of young roots were used to determine genetic diversities of the plants using standard methods of DNA electrophoresis and polymerase chain reaction (PCR).Taxonomic key for the six varieties were constructed using similarities and dissimilarities in their features. SPSS software 13.00 was used to analyze the data and Duncan’s multiple range test was used to separate the means at 5% (p<0.05). Morphologically the plants were similar in many respects but differences occurred in many layers of neutral flowers of ‘Mmemme’(5-15) and ‘Obuo odaa’(5-16) varieties and also in the sizes and shapes of the fingers of their fruits. Anatomical study showed differences in the stomatal distributions (6- 11 to 39- 90) in lower and (49- 62 to128- 150) in upper epidermal layers, among the varieties. Primordial adventitious root appeared in Akpukpoike cultivar only. Random Amplified Polymorphic DNA analysis revealed genetic diversity among the six varieties. The first similarity cluster consisted of Obuo odaa, Unele Mmemme, and Unele Ojii, while the second similarity cluster consisted of Unele Ocha, Akpupkoike and Egbela. Phytochemical analysis revealed in their roots that Unele Egbeala had highest content of Alkaloid (1.530 ± 0.010 mg) while Mmemme and Akpukpoike had no alkaloid in their stems. Unele Egbeala had highest content of tannin (7.400 ± 0.100 mg) while unele Ocha had the least (2.333 ± 0.065). Unele Obuo Oda had highest content of saponin (3.400 ± 0.030 mg) and flavonoid (1.100 ± 0.010 mg) while Egbeala had the least saponin in the stem . Egbeala and mmemme had no flavonoid in their stem. Unele Ocha had highest content of alkaloid (2.900 ± 0.030 mg) and phenol (0.620 ± 0.010 mg) in their stems while Egbeala and mmemme had no Phenols. The mineral contents results showed the presence of calcium, potassium, and iron in varying proportions with potassium being the highest. The study generated descriptive dissimilarities and similarities in the characters of six varieties of Musa sapientum. The characters that were of discontinuous variation were used for construction of dichotomous taxonomic keys that makes identification and classification of banana species easier.