Screening of Linum usitatissimum Lines Using Growth Attributes, Biochemical Parameters and Ionomics Under Salinity Stress

Salt stress causes plants to undergo metabolic and physiological disturbances, affecting growth, development, quality, and yield. With the increasing demand for food in the world and this environmental problem, the cultivation of salt-tolerant varieties or lines of crops is needed to compensate for the demands of food for mankind. This study was designed for salt tolerance problems; the four lines of Linum usitatissimum in terms of the plant’s agronomic attributes, yield, different metabolites (secondary and primary), antioxidant enzymatic activities, endogenous hormones, lipid peroxidation and ion analysis. This research was completely randomized-design (CRD) and four lines of flax (Alsi ARI-50, Alsi ARI-22, Alsi ARI-20 and Alsi ARI-1) were raised using water (control) and 150 mM NaCl in irrigation water. Salinity had a negative impact on different growth parameters, photosynthetic pigments-level (Chlorophyll a, Chlorophyll b, total chlorophyll and chlorophyll a/b ratio), Indole-3-acetic acid (IAA), and different essential ions. On the other hand, at the same salt concentrations, carotenoid content, sugar level, total protein, lipids, phenolic content, proline amount, flavonoid, tannin, β carotene, antioxidant level, lipid peroxidation, catalase activity, guaiacol peroxidase activity, ascorbic acid, salicylic acid, sodium and chloride ions significantly increased. Based on the present study, it was concluded that Alsi ARI-50 and Alsi ARI-22 showed higher salt tolerance compared to the other lines based on measured parameters. So, these lines are recommended to be used in the salinity area and also in the breeding programme.