Variabilidade genética de Dipteryx alata Vogel (Leguminosae): novos marcadores microssatélites, fluxo de pólen in situ e ex situ e genética da paisagem em escala local

• Autor(a) principal: Guimarães, Rejane Araújo
• Data de Publicação: 2018
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000005mzq
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/10919
• topic: Análise de parentesco; Fluxo gênico; Microssatélites; Illumina MiSeq; Spatial genetic structure - SGS; Parentage analysis; Gene flow; CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA

Dipteryx alata is a Neotropical tree widely distributed throughout the Brazilian Cerrado. Popularly known as baru, it is one of the most promising Cerrado species for domestication and cultivation due to its wide potential use. The general goal of this work was to assess reproductive system and pollen-mediated gene flow patterns of in situ and ex situ conditions and to evaluate how landscape may influence intrapopulation genetic structure. New microsatellite markers were developed using high performance sequencing technologies, then the ten most polymorphic were selected and used in this work. The evaluation of the reproductive system and pollen dispersal was carried out in a germplasm collection (ex situ) located at the Universidade Federal de Goiás and in one natural population (in situ) in Orizona-GO, central Brazil. The natural population was also used to evaluate landscape influence on intrapopulation genetic structure in adult and juvenile trees. In situ and ex situ conditions showed a high cross fertilization rate (tm = 0.815 and tm = 0.934), respectively, confirming that the D. alata presents a mixed-mating system, predominantly allogamous. The number of seeds sharing the same pollen donors was high, indicating a low number of pollen donors per tree under both conditions. This may be related to the proximity between groups of trees, considering that there is less cross-pollination between groups of more distant trees. Another factor that may have influenced cross-pollination over long distances is the heterogeneous landscape due to habitat fragmentation. The results indicate the presence of a positive and significant spatial genetic structure (SGS) in both stages of life (adults and juveniles) with the highest Sp value in juveniles. Bayesian cluster analysis showed the formation of two groups in both adults and juveniles. Juvenile individuals presented greater interference from landscape compositions. Thus, the inclusion of the landscape features brought an explanation gain to the pattern of intrapopulation genetic structure in the D. alata species. These results are important to support more efficient conservation strategies for this species.