Limitação da dispersão pela distância e diversidade genética das sementes dispersas de palmito Juçara em fragamentos da Mata Atlântica

• Autor(a) principal: Lucas, Marília Souza [UNESP]
• Data de Publicação: 2016
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/155835; http://www.athena.biblioteca.unesp.br/exlibris/bd/capelo/2017-08-24/000889981.pdf
• topic: Genetica vegetal; Sementes; Animais frugivoros; Variação genética; Palmito; Mata Atlântica

Seed dispersal allows the seeds to be carried away from the parent plant, leading to the colonization of new habitats and escape from areas with higher mortality. Seed dispersal by animals is a complex process influenced by several factors, including the number and behavior of dispersers. Large frugivores are important to long-distance seed dispersal, they can connect fragmented populations and promote gene flow. Longer dispersal events also promote greater overlap of the seed rain from different plants in the population, decreasing the spatial genetic structure at fine scales. Therefore, the loss of these animals can reduce the dispersal distance, increasing the deposition of seeds under the mother plant and therefore increasing the genetic structure in the initial stages of recruitment. In this context, the present study investigated the seed dispersal distance limitation and the genetic diversity of dispersed seeds of E. edulis using molecular tools. We hypothesized that the dispersal of seeds and genes would be reduced in forest fragments that no longer have large-body disperser birds, such as toucans and cotingas. For this, we collected seeds dispersed in 15 sampling stations arranged in two forest fragments and two more preserved forest remnants. In addition, we collect stem samples of reproductive palms within an eight meter-radius from the seed traps. We used eight microsatellite molecular markers to estimate genetic diversity (heterozygosity, allelic richness and inbreeding coefficient), assign maternity and calculate genetic relatedness between seeds. There were no differences in genetic diversity between adults and seeds when comparing the defaunated fragments and large forest remnants. In general adults presented higher levels of heterozygosity, lower allelic richness and inbreeding coefficients. Less than 2% of the seeds were assigned maternity to neighboring adult...