NUMERICAL TAXONOMY AND MORPHOLOGICAL VARIABILITY OF THE GENUS ZIZIPHUS IN KATSINA STATE, NORTHWEST NIGERIA

Abstract

The genus Ziziphus is a tropical genus that is native to the Northern hemisphere. The identification of the species in the genus is confusing due to their phenotypic diversity. In this study, numerical taxonomic approach was employed to identify the species in Katsina and to evaluate the useful characters to be use in delimiting the species. A total of 40 specimens were collected and subjected to morphological examination using both qualitative and quantitative characters. The result of the multivariate analysis revealed four major clusters at Euclidean distance of 0.58 and cophenetic correlation coefficient value of (r)=0.675. The result revealed that Ziziphus is represented by four species in Katsina, namely: Z. spina-christi, Z. mauritiana, Z. mucronata and Z. abyssinica. The petiole length, seed weight, leaf length are the important characters that were useful in delimiting the species with coefficient of variation of 41.06 %, 39.08 % and 33.67 %, respectively.

Keywords

• Katsina
• Morphological variability
• Numerical taxonomy
• Ziziphus