Morphometric Studies of Representative Species in Three Tribes of Euphorbiaceae

Morphometric studies have been shown to be highly efficient in plant classification. A morphometric study was carried out to examine the phenetic relationships among and within representative species from three tribes of Euphorbiaceae in Nigeria using morphological characters. Fifteen samples of the species of Euphorbiaceae were collected from Ibadan representing the three tribes. Twenty six qualitative and quantitative morphological characters of the studied taxa were examined. Data recorded from the morphological characters were scored and converted to binary numbers necessary for generating clusters of the Operational Taxonomic Units (OTUs). PCA-biplot and cluster analysis were used to determine the relationships between the studied taxa. The result of the morphological study of the species of Euphorbiaceae revealed that all the species had simple leaves. The dendogram generated from the cluster analysis of the studied taxa grouped the fifteen species into two main groups. Species within the same cluster display greater similarity when compared to those in the other cluster. Acalypha hispida, A. indica, A. godseffiana, A. fimbriata, A. wilkesiana, Jatropha integerrima, J. gossypifolia, J. multifilda, J. podagrica, J. curcas, Euphorbia heterophylla, E. graminea in one group and E. hyssopifolia, E. hirta and E. milii in another main group. The stem, petiole and leaf surfaces played a significant role in the delimitation of the species. The results from this study have highlighted the existence of similarity and dissimilarity among the different species of Euphorbiaceae. Key words: Euphorbiaceae, Dendrogram; morphometry; cluster analysis; PCA-biplot.