Diversity, genetic structure and core collection of mangaba (Hancornia speciosa) genebank

Abstract

This work was developed with the objective of characterizing the variability and genetic structure of matrices and progenies of the Mangaba genebank of Embrapa Tabuleiros Costeiros, to de ne a core collection. From the matrix of seven accessions, 289 individuals were generated, evaluated by nine SSR markers. The characterization of genetic variability was performed from the estimates: Average number of alleles observed (Na = 5.63) and effective (Ne = 2.71); Shannon Information Index (I = 1.04); Heterozygosity observed (Ho = 0.45) and expected (He = 0.51); Fixation index (f = 0.13); Percent polymorphism (%P = 90.47); and, Number of private alleles (Nap = 20). The Analysis of Molecular Variance (AMOVA) identi ed that the largest proportion of genetic variation is present within accessions (92%). The estimates of genetic differentiation (G ST and R ST ) were considered low (< 0.05) to moderate (0.05 to 0.15) magnitude. Multivariate analyses (PCoA, Rogers and Bayesian genetic diversity) did not discriminate the accessions according to origin. The formation of the core collection allowed retaining 94.90% of the identi ed alleles. The accessions present genetic variability to be explored in mangaba conservation and genetic improvement programs.