Effects of salinity stress on seedling biomass, physiochemical properties, and grain yield in different breeding wheat genotypes

The salinity tolerance of 17 breeding wheat genotypes along with three local varieties was evaluated under control and salinity stress (160 mM NaCl) conditions. At the seedling stage, several growth and physiological traits were measured. Moreover, the investigated genotypes were assessed in terms of grain yield across four saline regions during the 2018-2019 cropping seasons. Salinity treatment significantly decreased in the root and shoot dry weights (RDW and SDW), photosynthesis rate (P-N), stomatal conductance (G(S)), transpiration rate (T-E), shoot K+ content (SK), root K+/Na+ (RKN), shoot K+/Na+ (SKN), root-to-shoot Na+ translocation (RTSN), and root-to-shoot K+ translocation (RTSK), but resulted in increased root Na+ content (RN), root K+ content (RK), and shoot Na+ content (SN). The results of additive main effects and multiplicative interaction analysis (AMMI) also indicated significant differences among test environments (E), genotypes (G), and their interaction effects (GEI). The PCA-based biplot revealed that grain yield strongly correlated with RKN and RK. Furthermore, the correlation among P-N, G(S), and T-E traits was strong and positive and had a positive correlation with RWC, MSI, RDW, and SPAD index. Considering our results, RK and RKN were identified as useful physiological tools to screen salt tolerance at the early-growth stage. According to the ranking patterns obtained by the average sum of ranks method (ASR) and grain yield, we observed that genotype number G5 had considerable physiological potential at the early-growth stage and also responded well to soil salinity at the farm; thus, this genotype can be promoted for commercial production.