Published online by Cambridge University Press: 15 November 2003
Introduction.Annona muricata L. is a fruit tree species of tropical origin whose fruit, the soursop, although having great potential, is not commercially exploited enough. So there is little information on this species and, in particular, on its germplasm characterization. Consequently, the purpose of our study was to estimate the genetic variability between nine soursop accessions using the RAPD marker technique. Materials and methods. By means of RAPD analysis, using the Jaccard's coefficient, a similarity matrix was generated between nine accessions, seven of them collected in Venezuela and two in Brazil. With these, a phenogram was obtained using UPGMA clustering analysis. The ordering of the accessions was also achieved by means of a principal component analysis. Results. Seventeen RAPD fragments were obtained, of which 14 were polymorphic. Average similarity was 0.5333, and ranged from 0.2627 to 1.000. The phenogram identified two groups, equal to principal coordinates analysis. The Venezuelan accessions showed more variability when compared with the Brazilian ones (Jaccard's coefficient of 0.5038 and 0.5442, respectively). Discussion. Compared with other studies on various fruit trees, that carried out here on A. muricata underlined a great genetic variability. The situation is thus favorable to undertake in Venezuela a breeding program in this still under-exploited fruit species.