Association of Artemisia Afra genetic diversity, and bioactive compounds using South African and Lesotho genotypes

Abstract

Artemisia afra L. (African wormwood) is a plant that grows in the northern, central, and coastal regions of South Africa, as well as in neighbouring countries such as Eswatini and Lesotho. It is mostly used for human medicine in rural areas, especially for flu, malaria, cancer, gastric/abdominal pains, steaming to prevent congestion of nose and many other health disorders. Besides being used for medicinal purposes, people use it to make cosmetics, bathing soap and tea. To maintain by-product quality as well as improvement of yield of essential oils, genetic, mineral and phytochemical analyses were performed. The samples were collected from four locations: Roma (RO), Mohale’s Hoek (MH), Wepener (WE) and Hobhouse (HO). The samples were sent to Kenya for Genetic diversity analysis because the International Livestock Research Institute (ILRI) specialises in genome analysis, and mineral analysis was performed at the University of Lesotho. Analysis of variance (ANOVA), unweighted pair group method with arithmetic mean (UPGMA), and principal component analysis (PCA) were used to interpret the data obtained. Genetic diversity differences were noted within Artemisia afra genotypes collected from the same location. Even though many genotypes of Artemisia afra were similar, there were some exceptions that were different from others. The results revealed other differences on the UPGMA dendrogram, where the clades were divided into clusters and formed smaller groups. The PCA also showed a very close relationship of genotypes, with very few genotypes appearing far from the rest. The differences were also noticed in the analysis of foliar minerals and phytochemicals. Some samples had high amounts of soluble compounds. The study revealed that Artemisia afra samples collected from MH, RO, WE and HO had high amounts of phenolic compounds, and some differences in quantities were noted.