Phenotypic divergence among upland rice genotypes

Abstract

Information about the genetic divergence among cultivars could be used in order to avoid the homogeneity in cultivation and the consequent vulnerability to diseases and plagues. On breeding programs, this information facilitates the choice of dissimilar parents that, when crossed, provide higher variability on segregating populations. The aim of this work was to evaluate the divergence among 12 genotypes of upland rice in two sites of Zona da Mata region in Pernambuco, Brazil, using agronomic characters. There were significant differences among the genotypes for nine of the 12 characters studied, while genotype x environmental interaction was observed for three characters. The genetic divergence ranged from 0.083 to 0.583 considering each pair of genotypes and for the genotypes that could be more widely used in both places. The highest divergence was found between Rio Parnaíba x BRSMG (curinga) and Rio Parnaíba x BRS (primavera). The genotypes clustering showed higher PB 5 separation than the other genotypes, while two other well defined groups were formed, mainly in relation to the behavior of the genotypes in Vitoria de Santo Antão, Pernambuco, Brazil.