Genetic variability in Capsicum spp. accessions through multicategorical traits

Abstract

Capsicum peppers originate from the American continent. Their culinary and medicinal potential, first exploited by indigenous peoples over 7000 years ago is vast, however more studies are needed. Despite the existence of germplasm banks that house hundreds of accessions of the genus, only a little of this diversity is seen in large markets. In this respect, the morpho-agronomic characterization of the accessions allows not only the identification of the existing variability, but also the agronomic and commercial potential of the genotypes. Therefore, this study proposes to characterize and estimate genetic divergence between accessions of the Capsicum germplasm collection at the Universidade Federal Rural do Rio de Janeiro (UFRRJ) based on multicategorical traits. The species were identified and 29 accessions were characterized in a greenhouse, based on 31 multicategorical descriptors of the crop. The collected data were subjected to the Cole-Rodgers dissimilarity index and to hierarchical clustering (Nearest Neighbor) and optimization (Tocher’s) methods. Tocher's method was considered the most suitable to group the accessions of the germplasm bank. Results indicate that the multicategorical descriptors properly assess the diversity in the chosen method and display the existence of high variability in the collection, which can be used in Capsicum spp. breeding programs.