Fine-scale spatial genetic structure and gene flow in Acrocomia aculeata (Arecaceae): Analysis in an overlapping generation

• DOI: 10.1016/j.bse.2017.02.005
• Publication Date: 2017-02-28T00:15:46Z
• Authors: Maircon Rasley Go...; Afrânio Farias de...; Elytania Veiga Me...; Murilo Malveira B...; Leide Gonçalves Cota; Dario Alves de Ol...; Vanessa de Andrad...; Fábio Almeida Vieira
• Keywords: Fixation index; Outcrossing; Germ plasm; Arecaceae; Ex situ conservation

Abstract This study aimed to assess the fine-scale spatial genetic structure (SGS) and gene flow among the developmental stages of Acrocomia aculeata (Arecaceae) in a natural population of the Brazilian savannah. The study was conducted in a 4.5 ha area using a population census composed of 72 adult and 144 juvenile plants. Six-hundred embryo samples were analyzed to investigate the gene flow of plant progenies. All individuals were genotyped using seven microsatellite loci . The microsatellite loci generated 10.1 alleles on average. Observed heterozygosity ( H o ) was lower than expected heterozygosity ( H e ) in all stages of development. The mean H o and H e values were 0.496 and 0.688, respectively. The A. aculeata population presented high genetic diversity despite its significant positive fixation index (0.279, p = 0.001). Significant SGS was observed for adults at the 2-m distance class and for juveniles at the 2 and 4-m distance classes. Average pollen flow distance was 105 m. High multilocus outcrossing rate was observed (1.2), indicating that the species is preferentially allogamous with evidence of self-incompatibility mechanisms. The A. aculeata population presents high potential for in situ and ex situ genetic conservation and germplasm collection.