Genetic diversity and reproductive system of Tarenaya diffusa

The Cleomaceae is a relatively small family comprising approximately 300 species distributed worldwide. Tarenaya is one of the main genera within this family and holds significant economic value. However, despite its beauty and remarkable diversity, it remains underrepresented in the ornamental plant market due to the scarcity of information regarding its ornamental potential. Therefore, the objective of this study was to investigate the genetic diversity among Tarenaya diffusa accessions through morphological characterization and to determine its reproductive system. Twenty-four accessions of Tarenaya diffusa were evaluated using morphological descriptors related to plant architecture, flower, and fruit traits to assess diversity. The reproductive mode was determined through the pollen/ovule (P/O) ratio. The experiment was conducted at the Laboratory of Biotechnology and Plant Breeding, CCA/UFPB. Data were subjected to dissimilarity analysis, from which a Euclidean distance matrix was generated, followed by clustering using Tocher’s optimization method. The results revealed wide genetic diversity among Tarenaya diffusa accessions, and the P/O ratio was 9.45. Accessions 7, 15, and 20, belonging to groups III and V, may be recommended for breeding programs with ornamental purposes. Regarding the reproductive system, Tarenaya diffusa was classified as a facultative cleistogamous species.