Genetic Diversity of Remaining Populations of Mangaba (Hancornia speciosa Gomes) in Restingas of Brazil

摘要

Mangaba (Hancornia speciosa Gomes) is a fruit species that is native to Brazil, and has social, economic and cultural importance. Knowledge of the genetic relationships between the remaining populations is essential in order to promote conservation strategies for these genetic resources. In the present study, it was evaluated the genetic diversity of 35 individuals from three remaining restingas areas in the states of Ceará (Iguape and Cascavel) and Pernambuco (Tamandaré), located in the Brazilian Northeast. Nine ISSR primers were used to determine the genetic variability. Sixty-one fully polymorphic fragments (100%) were generated. The largest (10) and smallest (5) number of fragments were obtained with the primers HB14 and HB12, respectively. The Shannon index (I = 0.40), the genetic diversity (H = 0.30), and the percentage of polymorphic loci (%P = 73.77%) were also estimated. Both the methods of UPGMA and the Principal Coordinates Analysis (PCoA) clustered individuals according to their place of origin. Genetic divergence was greater within population (64%) than between them (36%). This may indicate a strong genetic structure, i.e., the gene flow rate between populations is low, favoring inbreeding. ISSR markers were efficient for the analysis of genetic diversity, for the identification of clusters, and for the estimation of the genetic distance between and within populations.