Chemical Mutagen Effect on Physiological Properties of Stevia rebaudiana Bertoni under Salt Stress

The present study was performed to evaluate the effects of different concentrations of ethyl methane sulfonate (0, 0.1, 0.2 and 0.5%) on some physiological characteristics of regenerated plants from calli of stevia at 30, 60 and 120 min under various levels of salinity stress (0, 50 and 100 mM of NaCl). This experiment was carried out based on completely randomized two-factorial designs with three replications. With respect to the result, the regenerated calli became dark and hidden in the medium under exposure time of 120 min, the length of stem regenerated calli was increased under exposure times of 30 and 60 min. Moreover, our data showed that EMS mutagenesis had a significant effect on physiological traits of regenerated stevia under salinity stress at the probability level of 1%. Consequently, the stevia mutants of M10, M11, and M19 showed the highest resistance to different levels of salinity which can be considered as potential samples for further breeding programs.