Diversidade e estrutura genética em escala fina de Syagrus oleracea (Mart.) Becc. determinada por meio de marcadores moleculares

Abstract

Syagrus oleracea is a species of Brazilian native palm, widely used in the manufacture of a variety of products and in both animal and human nutrition. In view of the extractivism potential of the above-mentioned species, the goal of this work was to characterize the genetic variability of individuals from different locations in the northern region of the state of Minas Gerais, and to examine the importance of these features in determining the genetic diversity. The acquired information may be relevanton determining strategies for species handling and conservation. 157 individuals from 7 populations of the north of Minas Gerais were assessed. For the genetic diversitycharacterization, 6 dominant molecular markers of the type "Inter Simple Sequence Repeat" (ISSR) were used. Looking at the results,one can observe that amplifications of 109locos occurred and that an average of 18, 17 alleles were found on each primer, values that demonstrated that the ISSR technique used was highly efficient. The Polymorphic Information Content (PIC) observed for each selected primer varied between 0.292 and 0.397. The genetic diversity indexes were observed, showing expected heterozygosity (He) and Shannon index (I) of 0.260 and 0.383, respectively. The number of alleles observed (na) among populations was 1.954 and the effective number of alleles (ne) was 1,606. Individuals of the populations are genetically structured in groups (demes) in a random and aggregate manner. The indirect gene flow value found was close to the expected limit value (Nm = 1.546). The results obtained in this research, demonstrate that the information of the species and the areas of its occurrence are very important to subsidize conservation strategies. Since it was observed evidence of high levels of kinship in the populations, possibly due to the low migration rates and geographic barrier, signs of overexploitation in the areas were detected, which consequently leads to a low rate of gene flow, thus occurring inbreeding between the population samples of Syagrus oleracea.