Selection of desert rose accessions with high ornamental potential

Abstract Adenium obesum belongs to the Apocynaceae family and is characterized as a succulent shrub with a multitude of botanical and morphological features of ornamental interest. The aim of this study was to evaluate the genetic dissimilarity of 28 accessions of A. obesum using morphological descriptors and multivariate techniques with the aim of pre-selecting the genotypes with the greatest ornamental potential. The distribution of the number of flowers throughout the year showed two flowering peaks in January and September. Twenty-one petal pigmentation patterns were identified, and 50% of the accessions had double-petal arrangement. The Gower’s algorithm and the UPGMA-generated dissimilarity matrix indicated the formation of three groups. While Tocher’s clustering method separated the accessions into eight groups showing greater ability to distinguish the evaluated genotypes. In conclusion, the multivariate analyses applied were effective in accessing the genetic diversity among the 28 accessions evaluated. The accessions ICA001, ICA005, ICA006, ICA018, ICA019, and ICA027 were preselected to compose the germplasm collection due to their high ornamental potential.