Genetic Variability and Phenotypic Divergence of Maize Progenies under Salt Stress Based on Morphophysiological Traits

Soil salinization is one of the major constraints to maize (Zea mays L.) production in semiarid regions, making the identification of genotypes with adaptation potential to saline conditions essential. In this context, assessing genetic variability and phenotypic divergence provides valuable information for selecting promising materials in plant breeding programs. Therefore, this study aimed to evaluate the genetic variability and phenotypic divergence of maize genotypes subjected to two levels of irrigation water salinity using genetic parameters and hierarchical cluster analysis. The experiment was conducted in a randomized complete block design arranged in a 21 × 2 factorial scheme, comprising 21 genotypes and two irrigation water salinity levels (0.14 and 3.0 dS m⁻¹). Biomass-related traits exhibited the highest broad-sense heritability estimates (0.66–0.79), high selective accuracy (0.72–0.96), and a predominance of genetic over residual variation, indicating strong potential for genetic selection. Hierarchical cluster analysis revealed substantial phenotypic divergence among genotypes and a clear separation between salinity levels. These findings demonstrate that biomass-related traits are promising criteria for the early selection of maize genotypes with potential adaptation to salt stress.