Impact of Salinity Stress on germination, Growth, Morphological Traits, and Genetic Diversity in Wheat (Triticum aestivum L.) Genotypes

The impact of salinity stress on the morphological characteristics, growth, and genetic diversity of ten genotypes of wheat (Triticum aestivum) were examined in this study. Salinity treatments at 50, 100, and 200 mM NaCl significantly influenced key growth parameters, including plant height, leaf number, branch retention, chlorophyll content, and vegetative fresh and dry weights. Genotypes 4 and 5 exhibited superior plant height under moderate salinity (50 mM), while higher concentrations (100 and 200 mM) caused substantial reductions across most traits. Chlorophyll content and vegetative fresh and dry weights were adversely affected by increasing salinity, with 200 mM causing the most pronounced stress effects. Genotypic interactions with salinity treatments demonstrated varying degrees of tolerance. Molecular analysis using Random Amplified Polymorphic DNA (RAPD) markers revealed significant genetic diversity among the wheat genotypes. Clustering analysis grouped the genotypes into four distinct clusters, reflecting varying levels of genetic similarity. Genotypes 1 and 6 were highly similar, forming a close cluster, while 5, 7, and 9 constituted a genetically distinct group. Crosses between divergent clusters, such as 1-6 and 2-9, could enhance genetic diversity and improve salinity tolerance. These results provide important information for breeding programs aiming at enhancing stress resilience in cereal crops by highlighting the significance of genetic diversity and environmental interaction in determining salinity tolerance in wheat.