Determining the effects of taurine on mitigation the damages caused by salt stress in wheat plant

In this study, the effects of taurine application to wheat (Triticum aestivum Yıldırım) plant on plant resistance against salinity stress were investigated. For this purpose, 100 mM NaCl, taurine (2 mM and 4 mM) were applied alone and in combination to wheat seedlings grown in hydroponic conditions for 9 days using Hoagland medium. Changes in morphological, molecular and biochemical parameters of the plants harvested 96 hours after these applications were examined. The stem length was decreased while the root length of the salt-stressed plants increased compared to the control group; these lengths increased significantly with taurine application. The relative water content, which decreased significantly with salt application, increased with taurine. It has been determined that salt stress reduces the total chlorophyll and carotenoid contents. Salt application increased peroxidase, ascorbate peroxidase and glutathione reductase activities of the wheat plant compared to the control conditions, while decreasing the superoxide dismutase and catalase activity. Taurine applications increased all antioxidant enzyme activities compared to the salt group. Antioxidant enzyme activity parameters were supported by isoenzyme results. Taurine application significantly reduced the hydrogen peroxide content and malondialdehyde level compared to salt application. With the salt stress, Na⁺ content of root and stem increased and K⁺/Na⁺ ratio decreased significantly. Significant increase in stem K⁺/Na⁺ ratio was measured with taurine application compared to salt group. Considering these results, it can be said that taurine application is effective in reducing oxidative stress by increasing the activity of the antioxidant system as well as providing K⁺/Na⁺ balance in order to increase the resistance of wheat plant against salt stress.