Molecular characterization of some Egyptian halophytes

Abstract

Egyptian halophytes are invaluable genetic resources for identifying genes associated with stress adaptation. Evaluating the genetic diversity among these plants is essential for both genotype identification and germplasm conservation. In this study, 22 samples from the Amaranthaceae and Aizoaceae families, along with 7 samples from the Poaceae family, were analyzed. Seven ISSR primers and five AFLP primer combinations were used to assess genetic relationships and population structure. High levels of polymorphism were detected, with an average of 100 % for ISSRs and 92.24 % for AFLPs in the Amaranthaceae and Aizoaceae families, and 91 % for ISSRs and 92.3 % for AFLPs in the Poaceae family. Multivariate analyses (UPGMA and PCoA) of the combined molecular data successfully assessed genetic variability allowing discrimination between different genera. Although variability of the collected samples resulted in high levels of polymorphism and a wide range of genetic diversity, similar genera collected from different places comprised the same cluster. This was clear in Halocnemum strobilaceum, Atriplex spp., Suaeda vera, Mesembryanthemum spp. and Phragmites australis genotypes. Further analysis using STRUCTURE software indicated K = 5 for the 22 samples of Amaranthaceae and Aizoaceae families, showing all individuals with a small degree of admixture. This mixed genetic contribution may refer to a probable mixed ancestry even though they belong taxonomically to the same order. Three pure groups among the 7 Poaceae samples were identified. The results highlighted the value of relying on both markers together to uncover more profound variations across genomes. The combination of AFLP and ISSR markers is a reliable tool for identifying genetic relationships and duplications in collected samples, aiding in conservation efforts.