Deciphering salinity tolerance during germination in bread wheat (Triticum aestivum L) through systematic phenotypic screening

Wheat is the major staple crop contributing about 20% of global calorie intake and ranks second to maize in worldwide production. It is vital to increase the production of wheat by about 70% by 2050 to feed world population. However, soil salinity is a critical constraint that impairs plant growth and development during germination stage. Therefore, identifying salt-tolerant bread wheat genotypes at germination stages is critical for mitigating yield losses. This study aimed to evaluate and identify wheat genotypes with superior germination performance under salinity stress. To achieve this objective, a comprehensive study was performed on 153 Ethiopian bread wheat genotypes obtained from Holeta agricultural research center. Seeds of each genotype were treated under four salinity levels for eight days. The results demonstrated that salinity stress had a significant effect on all measured 17 traits. Salinity markedly reduced growth parameters (SL, RL, SH, SFW, SDW, RFW and RDW), physiological traits (SRWC and RRWC), and germination indices (GP, GVI, SI), which showed strong correlations with salt tolerance. In contrast, mean germination time (MGT), time to 50% germination (T50), and shoot height reduction (SHR) increased under salinity stress. The substantial genotypic variation observed among the 153 Ethiopian bread wheat genotypes under salinity stress indicates the presence of valuable genetic diversity for salinity tolerance at the germination stage, providing promising resources for breeding salt-tolerant wheat cultivars.