EVALUATION OF RANDOM AMPLIFIED POLYMORPHIC DNA FOR SPECIES IDENTIFICATION AND PHYLOGENETIC ANALYSIS IN STYLOSANTHES (FABACEAE)

Random amplified polymorphic DNA (RAPD) was assessed for its suitabili ty as a tool to be used in the identification of taxa from the genus S tylosanthes (Fabaceae, Papilionoideae, Aeschynomeneae). Five random pr imers were used to 'fingerprint' accessions from seven species in the genus, and generated RAPD profiles that were species-specific, Data we re used to examine evolutionary relationships between taxa, employing both clustering and ordination techniques, and the results were compar ed with those from a previous cladistic analysis of chloroplast DNA (c pDNA) restriction fragments. Both multivariate approaches indicated re lationships that were generally similar to those obtained by RFLP anal ysis of cpDNA. However, while cluster analysis grouped together all ac cessions within species, ordination placed certain accessions of S. hu milis, S. macrocephala and S. capitata into separate groups. Experimen ts to test the assumed homology of comigrating RAPDs estimated 85.7% h omology for accessions within species, and 53.8% homology for accessio ns between species. The value of RAPD data in systematics is discussed .