Chloroplastic and nuclear diversity of endemic Prunus armeniaca L. species in the oasis agroecosystems

Tunisia is characterized by the presence of specific seed-propagated apricot (Prunus armeniaca L.) material which is found in the oasis agroecosystems. In order to highlight the genetic diversity, population structure, and demographic history of this germplasm, 33 apricot accessions collected from six different oasis regions in southwestern Tunisia were genotyped using 24 microsatellite markers. A total number of 111 alleles was detected with an average of 4.62 alleles per locus. Bayesian model-based clustering analysis indicated four subdivisions within the collection sampled that corresponded mainly to the geographic origin of the material. The analysis of the 33 accessions using chloroplast markers allowed the identification of 32 haplotypes. Overall, the present study highlighted the high Tunisian apricot's diversity in the traditional oasis agroecosystems with low genetic differentiation. Understanding the structure of seed-propagated apricot collection is crucial for managing collections in regard to adaptive traits for Arid and Saharan climates as well as for identifying interesting genotypes that can be integrated into international coordinated actions of breeding programs.