Effect of seed priming with salicylic acid on seed germination and seedling growth of Hibiscus sabdariffa under drought stress

In order to evaluate the effect of seed priming with salicylic acid on seed germination and seedling growth of Hibiscus sabdariffa under drought stress a factorial experiment was conducted in a randomized complete block design with four replications. First factor was included different levels of drought stress (0, -2, -4 and -6 bar) and the second factor was different levels of seed priming with salicylic acid at four levels (0, 0.5, 1 and 1.5 mM). Results showed that among different levels of seed priming, priming with 1 mM salicylic acid increased germination rate and coefficient of velocity of germination, compared with control by 42 and 14%, respectively. Salicylic acid concentrations of 0.5 mM enhanced, root length, shoot length and seedling dry weight compared with the control treatment, by 17, 18 and 27%, respectively. At drought conditions, priming reduced the mean germination time, significantly. Moreover drought stress decreased all measured traits except mean germination time. Overall, results showed that seed priming with salicylic acid in stress conditions improved roselle germination.