Genetic diversity and population structure of Ethiopian basil (Ocimum basilicum L.) accessions using DArTseq markers

Abstract

In Ethiopia, basil is the most widely used aromatic and medicinal herb. Despite being widely available across the nation and utilized for a variety of purposes for centuries, little is known about the degree of genetic variability in sweet basil. Thus, 62 basil accessions that were collected from various locations in Ethiopia were examined for genetic diversity and population structure, and genome-wide SNPs were created using genotyping by sequencing (GBS). The observed and expected heterozygosis are (0.01–0.02) and (0.13–0.33), respectively. The gene diversity index (GD) ranged from 0.13 to 0.29, with an overall mean of 0.13. Moreover, the polymorphic information content (PIC) varied from 0.23 to 0.37, with an average of 0.37. The Shannon index (I) ranged from 0.01 to 0.41, with an average of 0.12. A total variation of 90 % and 1 % within and among populations, respectively, was revealed using analysis of molecular variance (AMOVA). Furthermore, genetic variation showed a coefficient of gene differentiation of 0.01 and a gene flow value of 2.013 among populations. The 62 basil accessions were divided into two genetic groups according to STRUCTURE analysis, unweighted pair group method (UPGMA), discriminant analysis of principal components (DAPC), and principal coordinate analysis (PCoA). This research confirmed the diversity and population structure of the Ethiopian basil. Therefore, the variation pattern in their genetic diversity can serve as a basis for the selection, breeding, and maintenance of basil in Ethiopia.