Diversidade e estrutura genética em populações naturais de Pterodon emarginatus Vogel (leguminosae)

• Autor(a) principal: Pinto, Marcos Vinícius Pereira
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/9102
• topic: Pterodon emarginatus; Microssatélite; Diversidade genética; Pterodon emarginatus; Microsatellite; Genetic diversity; CIENCIAS AGRARIAS::AGRONOMIA

Genetic diversity is a fundamental component for the survival of any species over evolutionary time, because it is the repertoire of possible responses to environmental pressures, which are dynamic and constant. Knowledge of the magnitude and structuring patterns of this diversity allows to understand how environmental and microevolutionary factors have interacted over time and shaped the populations. Microsatellite markers have been the most used molecular tool in recent decades for mapping studies of diversity and genetic structure due to its high degree of polymorphism, genomic abundance and codominant nature. For native species these markers rarely are available, however, the regions flanking the microsatellites are usually conserved among evolutionarily close species, which allows the transfer of these markers. Pterodon emarginatus Vogel, popularly known as Sucupira branca, is a tree plant belonging to the legume family. This species is widely used for medicinal purposes because of the broad properties of its secondary compounds. In addition, it provides rigid wood of interest for construction and is also used as an ornamental species. Despite the substantial number of studies directed to the medicinal potential, little is known about the genetic diversity present in this species. Therefore, the objectives of the work were to transfer to P. emarginatus microsatellite markers developed for Dipteryx alata and to access the diversity and genetic structure in natural populations of P. emarginatus. For this, the cross-amplification of 25 primers were tested and 12 natural populations were genotyped for 6 loci. Of the 25 primers tested, 2 (8%) showed good amplification and polymorphism pattern. The set of markers used revealed a total of 45 alleles for the 12 populations evaluated, with a mean of 7.667 per locus. This value ranged from 4 (DaE12) to 22 (PVESTBR067). Populations showed intermediate levels of genetic diversity (He = 0.555) and greater variability within populations than among populations. Small but significant levels of inbreeding were detected due to both the mating system and the population subdivision (f = 0.07; Fst = 0.073). These results support that the species presents a mixed mating system, being preferentially allogama. The pattern of divergence among populations was moderately structured in space (Mantel = 0.440, p <0.002) indicating a profile of large continuous populations with significant levels of gene flow over distances up to approximately 400 km.