Effect of seed priming on germination and seedling growth of Barli 21 tobacco varieties under PEG and salinity stress conditions

Aim & In order to evaluate the effect of priming on seed germination Burley 21 tobacco varieties, a research was conducted in the autumn of 1392 in Urmia Tobacco Research Center. In the first part, a completely randomized design with 26 treatments and 3 replications were conducted. Treatments were one control and 4 levels of polyethylene glycol (0.5, 1, 1.5 and 2%) at different periods of 1, 2, 3, 5 and 10 days, and water (priming) at different periods of 1, 2, 3, 5 and 10 days. In the second part, a factorial completely randomized design was conducted with 3 factors and 3 replications for the first factor, the concentrations of -0.5, -1, -1/5 and-2 MPa polyethylene glycol and distilled water, and for the second factor they were 1, 2, 3, 5 and 10 days priming and salinity; for the third factor were 1, 2, 3 and 4 dS m for per was petri dish. In the first part of experiment, the treatments on time and germination percentage at 1% level had a significant effect. The mean time of germination using tobacco seed priming with polyethylene glycol and distilled water significantly decreased. Germination in the priming effect for 3, 5 and 10 days significantly was reduced. In the second part of the experiment, seed priming had significant effect on germination time, germination rate, germination index, germination rate and germination percentage at 1 % level, time duration of seed priming on germination time, germination rate had significant effect at 1% level. Germination time in petri dish significantly increased with increasing salinity; while the germination rate and speed germination index declined. In conclusion, priming tobacco, resulting in improved germination rate, rate of germination and speed germination. The best priming time was 1 and 1.5 % polyethylene glycol and the duration of a day. Considering the importance of tobacco seed germination rate, it is required to use concentrations of 1 or 1.5% of polyethylene glycol to be treated one day before.