Unraveling the dynamics of salt stress response in wheat cultivars: insights into growth inhibition, antioxidant enzyme activity, and AOX gene expression

Three different wheat varieties were the subject of an experiment to see how salt affected seed germination and seedling development. BARI Gom20 (Gourab) was employed as a salt sensitive variety, whereas BARI Gom28 and BARI Gom25 were utilized on salt tolerant types. Three replications, three salinity levels (0, 150, and 200 mM of NaCl), and a complete randomized design (CRD) were used to set up the experiment. All the wheat varieties had a noticeable growth loss due to salt stress. Wheat growth was inhibited more in salt-sensitive cultivars compared to salt-tolerant cultivars, BARI Gom28 showed overall stronger salt tolerance. When wheat was tested for salt tolerance, there were striking variations in the antioxidant enzymes (catalase, peroxidase, and ascorbate peroxidase) that were present. The effect of rising salt content, catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) activity varied between salt-sensitive and salt-tolerant cultivars. Intriguingly, TaAOX1a and TaAOX1c gene expression levels increased in BARI Gom28 as the degree of salt concentration increased. Additionally, the salt-tolerant BARI Gom28 had smaller accumulations of hydrogen peroxide, malondialdehyde, and higher activity of the antioxidant enzymes than the salt-sensitive Gourab, indicating that the latter had comparatively less oxidative damage. However, the contribution of antioxidant enzymes and AOX gene family to salinity stress response in wheat is further requisite to unlock the molecular functions. Exploring the molecular mechanism for lowering salt stress in wheat cultivars will require more research.