02130naa a2200133 a 450000100080000000500110000800800410001910000160006024500980007626000090017452017060018370000170188977300900190616518392004-04-06       1998    bl uuuu     u00u1 u    #d1 aCOLOMBO, C.  aAFLP and RAPD markers for study the genetic diversity of cassavas (Manihot esculenta Crantz).  c1998  aAbstract: The genetic diversity of the species Manihot esculenta Crantz was approached by few authors, through several methodologies (botanical descriptors, proteins and DNA polymorphism). In a general way, a weak structuring of the genetic diversity of this species is attributed, being believed to be inherent to the history of this plant in the American continent, that is to say, the association among the vegetative mutiplication way, the constant changes between producers and the genetic recombination of genetic materials. In recent study based on RAPD polymorphism (Random Amplified Polymorphic DNA), an important genetic structuring was studying a group of etnocultivares from medium Rio Negro, in relation to genotypes from several American places. With the objective of reviewing this structuring the same botanical material was analyzed through a new class of molecular markers, more stable than RAPD, that is to say, the AFLP (Ampified Fragment Length Polymorphism), although both just evidence the dominance events. The results of this study confirmed the genetic structuring revealed by RAPDs. The cophenetic values obtained in the dendrogram construction (UPGMA mode) starting from the two markers they were correlated with the values of genetic similarity calculated starting from the presence-absence of the bands (test of Mantel) revealing a better check of AFLPs with relationship to RAPDs (r = 0.78 against r = 0.57, respectively) to explain the obtained genetic structuring. Corroborating these results, a larger variance was observed in the first two axes of the Principal Coordinates Analysis for the markers AFLPs with relationship to RAPDs (30.5 against 24.2, respectively).1 aVALLE, T. L.  tRevista Brasileira de Mandioca, Cruz das Almasgv. 17, p.14, nov., 1998., Suplemento.