Response of Tobacco Cultivars (Burley 21 and Virginia VK51) to EMS on the Biochemical Characteristics under Drought Stress Conditions

The experiment was carried out during the seasons 2021/2022. To study the effect of soaking seeds with EMS in improving the tolerance of two tobacco varieties (Burley 21 and Virginia VK51) to drought stress. The seeds were treated using three concentrations of the mutagen (0.1, 0.5 and 1%) with a soaking time of (8) hours. In addition, to induce drought stress, polyethylene glycol (PEG) was used at concentrations (15, 30 and 45%). The experiment was conducted according to a randomized complete block design (R.C.B.D.) with three replicates at the Damsarko farm- Lattakia- Syria. Some characteristics (malondialdehyde, poly phenols, total soluble sugars and Nicotine content in leaves) were studied. Treatment with EMS at a low concentration (0.1%) led to an decreased in the malondialdehyde, poly phenols, total soluble sugars, Nicotine Content. However, High concentration of EMS at (0.5 and 1%) caused an increase in the studied indicators of two tobacco varieties. High concentration with PEG, caused an increase in the malondialdehyde, poly phenols, total soluble sugars, Nicotine Content. More clearly with increasing applied stress. Thus, it can be suggested to soak seeds at the concentration (0.1%) EMS for its role in improving some characteristics of tobacco under drought stress conditions.