Development of microsatellite loci for genetic diversity characterization of annatto (Bixa orellana) accessions

Abstract

The aim of this project is to characterize the genetic diversity of 63 accessions of annatto (Bixa orellana), maintained at the Germplasm Bank of the Instituto Agronômico (IAC), using microsatellite markers. Microsatellite loci will be developed for the species through an enriched genomic library. Subsequently, the loci obtained will be used to characterize the accessions. We intend to estimate, for the groups of genotypes originating from three Brazilian regions (North, Southeast and Midwest), the allelic and genotypic frequencies, genetic diversity indices such as number of alleles per locus, percentage of polymorphic loci, average observed and expected heterozygosity, Wright's fixation index and Nei's diversity index, verifying the level of genetic diversity of the collection and distribution of variability among and within regions. A cluster analysis will be conducted calculating the distance estimates based on sharing of alleles, resulting in a dissimilarity matrix for individual accessions to view the accessions that are genetically more distant, which will allow the selection of divergent parents to be use in breeding programs. (AU)