Genetic variation and phylogenetic relationships based on RAPD analysis insection Caulorrhizae, genus Arachis (Leguminosae)

Wild Arachis germplasm includes potential forage species, such as the rhizo matous Arachis glabrata and the stoloniferous A. pinto and A. repens. Comme rcial cultivars of A. pintoi have already been released in Australia and in several Latin American countries, and most of these cultivars were derived from a single accession of A. pintoi (GK 12787). Arachis repens is less pr oductive as a forage plant than is A. pintoi. However, it can be crossed wi th A. pintoi, and thus has good potential as germplasm for the improvement of A. pintoi. Arachis repens is also used as an ornamental plant and ground cover. Many new accessions of these two stoloniferous species are now avai lable, and they harbor significant genetic variability beyond that availabl e in the few older accessions, previously available. Therefore, these new a ccessions need to be conserved, documented and considered in terms of their potential for crop improvement and direct commercial use. Sixty-four acces sions of this new germplasm were analyzed using RAPD analysis. Most of the accessions of A. repens grouped together into a clearly distinct group. In general, the accessions from the distinct valleys of the Jequitinhonha, Sao Francisco and Parana rivers did not group together, suggesting there is no t a tight relation between dispersion by rivers and the geographic distribu tion of genetic variation in these species.