Caracterização molecular e variabilidade genética de acessos elite de mandioca para fins industriais

Abstract

Molecular markers are useful tools for the molecular characterization of cassava accessions since they present high capacity to detect information within the genome. The aim of this research was to characterize through RAPD molecular markers, 20 industrial cassava accessions conserved in the Cerrado Cassava Regional Germoplasm Bank ("Banco Regional de Germoplasma de Mandioca do Cerrado"-BGMC). Upon laboratory conditions, the accessions were evaluated though RAPD markers, being afterwards estimated by the matrix of genetic similarity among the accessions, through the Jaccard index. The analyses through 11 primers generated a total of 120 RAPD markers, among which 74 (62%) were polymorphic, revealing the presence of high genetic variability within the group of evaluated accessions. The clustering analyses revealed the formation of a single strong group, comprised of the accessions BGMC 1130, BGMC 788, BGMC 1270 and BGMC 1107, which indicates that the cassava genetic breeding hybridizations among these accessions should not be prioritized, upon risk of endogamy effects. The accession BGMC 436 was the most divergent as compared to the others and, as it expresses high productive potential within the Central Brazil Cerrado, it represents a good option as parent for the cassava breeding in this region. The study confirmed that the RAPD markers are efficient for the determination of genetic variability among evaluated accessions and that within the group there is high genetic variability useful for the plant breeding.