Salt stress is one of the most detrimental factors adversely affecting cotton, and cotton plants display considerable diversity in salt tolerance. Developing cultivars that can withstand salt stress is imperative to meet the growing cotton demand for the textile industry. High-yielding and salt-tolerant cotton cultivars could be developed with the help of efficient salt-tolerance screening methods. The primary objective of the current study was to efficiently screen cotton genotypes for salt tolerance using salt tolerance indices such as tolerance index, mean productivity, geometric mean productivity, yield index, stress susceptibility index, stress tolerance index, and modified stress tolerance index under control and three salt stress conditions (10 dS/m, 15 dS/m, and 20 dS/m). The effects of genotype, environment, and their interaction on seedling dry weight were highly significant. As the salt stress level increased, there was a consistent decrease in the dry weight of the seedlings with different genotypes exhibiting varying levels of performance, suggesting the presence of genetic variability. Salt tolerance indices and combined ranking criteria indicated that the genotypes Hataf-1, FH-158, CIM-446, and VH-305 exhibited the highest level of salt tolerance. Conversely, the genotypes Cyto-178, VH-259, MNH-996, MNH-992, NS-131, and AA-703 had the highest sensitivity to salt stress. The identified salt-tolerant genotypes could be cultivated in saline conditions and should be considered for future breeding programs. The findings also proved that the salt tolerance indices employed in this study are valuable for efficiently screening cotton germplasm to enhance salinity tolerance in breeding programs.

Keywords: cotton, seedling, salinity, tolerance indices, salt tolerance, dry weight.