Variabilidade genética em populações de Erythrina velutina Willd. por meio de isoenzimas

Abstract

The natural forests represent an immeasurable source of genetic resources, but many of these resources are being impacted by human action. Among the species most destroyed Erythrina velutina Willd, popularly known as "coral tree", can be highlighted. Although this species has timber value, ecological, ornamental, medicinal and industrial value, there are not reports about its genetic diversity. In this study we assessed the genetic diversity of the E. velutina individuals, using biochemical markers for conservation of genetic resources of this specie. Young leaves were collected from thirteen individuals, located in the Lower São Francisco River in the semi-arid region and the coastal region of the Sergipe State. The samples were submitted to eight enzyme systems where two showed no activity and the others were polymorphic. The six selected enzyme systems (ADH, EST, IDH, MDH, PO and SOD) produced fifteen loci, in which one was monomorphic (Sod-5), and a total of thirty-nine alleles. Analysis of allele frequencies indicated the presence of a total of twelve low-frequency alleles and fifteen alleles that suggested the existence of variability among the three localities. The species are in equilibrium at studied locations according to the excess of the homozygotes indicated by the fixation index. The levels of genetic diversity measured by mean number of alleles per locus, percentage of polymorphic loci and expected heterozygosity were high, indicating the localities studied populations as potential for in situ conservation and seed collection for the restoration of degraded areas.