Assessment of Salinity Tolerance in the Selected Genotypes of Cotton

In order to evaluate the salinity tolerance of cotton genotypes, ۱۴ selected genotypes together with a commercial cultivar (as control) were compared in laboratory and farm in during the ۲۰۱۴-۲۰۱۵ growing season. The aim of this study was recognition salinity tolerant genotypes at the germination stage and found the relationship between laboratory and farm conditions to reduce costs and minimize the time needed to improve tolerance to salinity. The laboratory study was performed as a factorial experiment based on a completely randomized design with three replications. The first factor was salinity at ۳ levels (۰, ۸ and ۱۶ ds/m) and the second factor was genotypes selected from ۱۸۰ imported varieties using a two-step selection in previous experiments. The measured traits include the percentage of germination (Ger%), stem length (SL), root length (RL), stem wet weight (SWW), stem dry weight (SDW), root wet weight (RWW), root dry weight (RDW), stem tissue water content (SWC), root tissues water content (RWC), seedling wet weight (SLWW), seedling dry weight (SLDW) and whole plant water content (PWC). Results showed that there are significant differences among studied genotypes for the mentioned traits at a ۵ or ۱ percent level. Salinity treatments have reduced the length of stem, root and wet weight of cotton seedlings. The TJ۱۸۹ genotype showed higher performance for GER (۹۱.۶), also TJ۱۷۸ for SL (۵۱.۶) and TJ۱۶۹ for RL (۷۰.۵). For SWW and RWW, genotypes TJ۱۲۰ and TJ۱۸۳ with ۳۶۲.۴ and ۵۳.۶ mg were higher than the control cultivar, respectively. Tj۸۲ the most seed cotton yield and Golestan the most earliness have among the ۱۵ genotypes.