Comparison of the effect of water deficit and salt stresses on the growth, sodium and potassium content of wheat (Triticum aestivum L.)

To study the effect of water deficit and salinity stresses on morpho-physiological characteristics of wheat seedling cv. Flat, a pot experiment was conducted in completely randomized design with three replications in Faculty of Agriculture, University of Yasouj, Iran, in 2015. The studied treatments were seven treatments including three levels of each water deficit and salinity stresses with similar osmotic potential (-2.47, -4.94 and -7.42 bar) together with a control treatment (Hoagland solution). Salinity and drought stresses were applied using sodium chloride and polyethylene glycol 6000, respectively. The results showed that shoot dry weight significantly decreased under the effect of salinity and drought stresses compared to control treatment. Drought stress increased root dry weight of wheat, so that the highest root dry weight was observed in polyethylene glycol of -7.42 bar. The maximum and minimum sodium content of shoot and root obtained from -7.42 bar salinity and control, respectively which have not significant differences with drought stress levels. The salinity of -7.42 bar significantly reduced shoot and root potassium content. The highest shoot to root potassium ratio obtained form control and the lowest from -7.42 bar salinity stress. Protein content and catalase and peroxidase enzymes activity significantly increased by increasing the salinity and drought levels. In general, the results of this study showed that salinity compared to water stress have higher negative influence on wheat which reduces shoot and root dry weight.