Estimation of the diversity of traditional varieties of cowpea in Acre with SSR markers

Abstract

The State of Acre is an important source of cupi bean diversity, with small farmers being the main responsible for its maintenance and conservation. Although it is of great importance for breeding, the genetic diversity of cowpea has not yet been properly determined and explored. Molecular markers are efficient tools to reliably estimate the differences between genotypes of the same species. The aim of this study was to determine, using microsatellite markers, the genetic variability of traditional varieties of cowpea cultivated in Acre. The 53 genotypes used were seeded and grown in pots until the production of fully expanded leaves for DNA extraction. Five microsatellite loci were used. Based on the presence and absence of bands for each marker, the Jaccard index was calculated. Multivariate analyzes were performed to verify the grouping of genotypes by the UPGMA, Tocher Optimization, Modified Tocher and principal coordinates methods. Genetic distances ranged from 0.00 to 0.81. There was high variability among the 53 genotypes, which were separated into 44 distinct groups. One genotype pair was identified as a duplicate. The divergent genotypes identified in this study can be indicated to compose cowpea genetic improvement programs.