Diversidade genética entre e dentro de populações de Cenostigma Tocantinum Ducke

Abstract

Cenostigma tocantinum (Caesalpinoideae) is arboreal and shrubby specie, native to Brazil and wood is used in building and tree in forestation projects. This study aimed to evaluate genetic diversity among and within of C. tocantinum populations by AFLP markers. Three populations were sampled in cities of state of Amazonas: Manaus, Parintins and Presidente Figueiredo, each population composed of 30 plants samples. 8 primers combinations were tested, of which four were selected for analysis: E+AGT/M+CAT, E+AGT/M+CTC, E+AGT/M+CAC, E+AGT/M+CCA. The percent of polymorphics locis was estimated, Analysis of Molecular Variance performed, dendogram builded and the populational differentiation and substructuration genetics patterns checked. From 186 locis disclosed, 132 (71%) were polymorphics. The value of genetic differentiation between populations (Fst) was 0,3662. The result Analysis of Molecular Variance imputed 36,62% and 63,38% of the variation among and within populations, respectively. The builded dendrogram based on AFLP markers revealed the formation of two groups, the Manaus and Parintins populations and the group of Presidente Figueiredo. The populational differentiation and substructuration genetic standards, revealed by L (K) and ΔK, demonstrate that populations have examined had populational substructures and share three clusters, being present in these three populations and distributed heterogeneous quite manner. The AFLP molecular markers are efficient for detecting genetic diversity in C. tocantinum and differentiating populations of different constitutions. The majority of genetic variability occurs within populations. For arboreal species, as C. tocantinum, used in urban forestation projects, the introduction of plants into news projects coming from appropiate sampling in other populations promotes genetic conservation of the specie.