Diversidade genética em populações de Myrsine umbellata (Primulaceae) em remanescentes da Floresta Atlântica

• Autor(a) principal: Costa, Thais Lazarino Maciel da
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/5115
• topic: Gene flow; Capororoca; Fluxo gênico; ISSR; Melhoramento Vegetal; Genética; Genética vegetal; Marcadores biológicos; 631.523

Population parameters inferred from genetic data are useful in the characterization of natural populations and important in determining priority areas for conservation, such as the Atlantic Forest, which has an extensive biodiversity, what makes the complete evaluation of the species not viable. Thus, genetic studies of some populations allow to interpret the community and to extrapolate the results to other similar species. Myrsine umbellata is a shrubby species, widely distributed in the Atlantic Forest, a pioneer, a facilitator in natural regeneration areas, with zoochorous dispersion and their fruits are important in the birds diet. In order to identify the genetic diversity between and within the populations, six populations of M. umbellata were sampled, which are: Macieira, Ibitirama, Iúna, State Park of Forno Grande, Santa Teresa and State Park of Blue Stone, totaling 63 individuals. 10 ISSR molecular markers were used to amplify 129 loci, obtaining 100% of polymorphism for nine primers. The data were submitted to similarities analysis between individuals by Jaccard coefficient, showing greater similarity between the Ibitirama and Iúna populations. The expected Nei diversity index (He) and the Shannon index (H ') in the populations ranged from 0.28 to 0.18 and 0.18 to 0.12, respectively, where the Macieira population showed the highest values and the Ibitirama population the lowest ones. The AMOVA showed that the most part of the genetic diversity occurs within populations (67.41%) than between populations (32.58%), with the statistical ØST presenting a high level of genetic differentiation of 0.32. The allelic flow estimated for the populations set was high (Nm = 1.24), but it is believed that this value is assigned to a historical gene flow when populations were part of metapopulations, before the forest fragmentation processes. An AMOVA was also accomplished to examine pairwise the FST values of the populations, and the values found indicate that the populations are moderate to highly structured. The UPGMA clustering method was used for both, individuals and populations, and two big groups were formed, confirmed by evaluation done by the program STRUCTURE best K, equal to 2 was obtained. The maintenance of genetic variability in populations is the basis of species conservation, therefore, these data indicate that conservation strategies for M. umbellata populations should prioritize population samples that are internal, as these are an important source of germplasm for in situ conservation