Phylogenetic Determination of Chenopodium quinoaBased on the Chloroplast Genes rbcL and matK

Abstract

Chenopodium quinoa is an Andean species of great interest because of its excellent nutritional quality and great adaptability to different environmental conditions. In addition, the high phenotypic diversity has caused difficulties in the correct taxonomic identification, and there are few studies on the phylogenetic relationships of quinoa in Colombia. Therefore, the objective of this research was to determine the phylogenetic relationships of quinoa with the matK and rcbL chloroplastid genes to characterize the genetic diversity in Colombian quinoa. Evolutionary analyses were performed using nucleotide substitution rates, pattern, base composition, and phylogeny construction. The rbcL gene presented approximately 1344 bp, and matK had 646 bp, which were translated into 434 and 215 amino acids, respectively. The nucleotide composition of the genes showed high percentages of similarity and identity with the Chenopodium quinoa sequences registered in GenBank and BOLD. Similar phylogenetic trees were obtained with the rbcL and matK genes, and both concatenated sequences grouped the accessions into clades. The results showed that Colombian quinoa has low rates of genetic differentiation that may be due to the domestication processes of the species, the lack of certified seeds, and the constant exchange of seeds between farmers in the principal producing areas of the Andean region.