Comprehensive seed priming assessment of Hibiscus sabdariffa L. in germination and seedling growth stage under salt stress

Abstract

This study was performed to appraise the effects of several seed pretreatment solutions and priming time on seed germination indices and growth characteristics of Hibiscus sabdariffa L. in various salt stress levels. Seed priming was accomplished by KCl (1 and 2 %), Na2SO3 (0.5 and 1 %), KNO3 (0.5 and 1 %), and Ca2CO3 (1 and 2 %) as halopriming and distilled water as hydropriming at 12 and 24 h priming durations and control (non-primed), then primed seeds exposed to four levels (0, 50, 100, 200 mM) of NaCl solutions. The highest germination percentage was observed in 12 and 24 h hydropriming (63.3 and 53.3 %) and non-primed (56.6 %) under normal condition, respectively. Besides, there was no germinated seed at 24 h priming by 0.5 and 1 percentage of KNO3. Under saline condition, 24 h 2 % Ca2CO3 had the highest germination percentage (43.3 %) in 50 mM, while 12 h treatment with 0.5 % Na2SO3 (33.3 %) had high germination percentage in 100 mM levels of saline conditions. Also, the highest germination rate index was observed in 0.5 % Na2SO3 with 12 h treatment time (4.05 and 3.95 respectively) in 50 and 100 mM levels of saline conditions. Overall, salt stress considerably reduced germination and growth traits of Hibiscus sabdariffa L. seedlings. Considering the effect of various seeds priming of Hibiscus sabdariffa L. on germination indices like germination percentage and mean germination time, the importance of priming duration and type of priming solutions could be concluded.