Intraspecific Morphological Variations among the Populations of Milicia excelsa, Pouteria adolfi-friedericii, and Prunus africana in Different Natural Forests of Southwest Ethiopia

Abstract

Plants have the ability to change their morphological and physiological traits in response to environmental variations. The objective of this study was to determine the intraspecific morphological variations among the populations of M. excelsa, P. adolfi-friedericii, and P. africana in southwest Ethiopia. Representative forests were systematically selected, and a total of ten transects of 160 m length were randomly laid at 100 m intervals, and 30 quadrats (20 m by 20 m) were laid along each transect line at 50 m intervals. Stem height, DBH, and bole length of trees for each species were measured in each quadrat. The intraspecific morphological variations among populations of each species were computed using hierarchical clustering and principal component analysis (PCA) with R.4.1.3. A total of 55 trees for M. excelsa in four forests, 232 trees for P. adolfi-friedericii in eight forests, and 184 trees for P. africana in five forests were measured. Accordingly, three, five, and three population clusters were identified for M. excelsa, P. adolfi-friedericii, and P. africana, respectively. The analysis of similarity (ANOSIM) indicated the presence of considerable dissimilarity among population clusters for M. excelsa and P. africana but was not significant at $p\le 0.05$ (R = 0.9, $p=0.17$ ). However, ANOSIM indicated the presence of considerable dissimilarity among population clusters of P. adolfi-freidericii, which was significant at $p\le 0.05$ (R = 0.9, $p=0.03$ ). Overall, there was a visible morphological variability among the populations of M. excelsa, P. adolfi-friedericii, and P. africana each at the different sites. Therefore, it is important to look for conservation strategies, such as domestication, to maintain and improve the variability and genetic quality among the populations in a wider scale of the ecological and social environment.