Abstract
Allium roseum (Alliaceae) is an important medicinal and aromatic plant of the Tunisian flora. It was extensively widespread in southern Tunisia, where it has been empirically used for its numerous therapeutic virtues. Twenty-two morphological and floral traits observed in a field collection of 14 populations of A. roseum, belonging to four different bioclimatic zones of Tunisia, were analyzed using multivariate analysis. The data underwent an analysis of variance and a principal component analysis. Significant differences have been showed between the populations for the studied characters and the cluster analysis revealed three main groups among the Tunisian A. roseum plants. Bioclimatic zone originality of studied population was not determinant criteria for the distribution of populations in several groups. There proved to be substantial genotypic variability in the Tunisian material for the phenotypic traits. Variation within the same bioclimatic zone was extremely important.