Medicinal barberry plants, belong to Berberidaceae family. Seeds of barberry have long period dormancy. Therefore, overcome to seed dormancy and increasing germination rate of seeds due to different methods will be useful. In this regard, two separate experiments were designed. In the first experiment, effect of different levels of Gibberellic acid (0, 600 and 900 mg.l-1 at 8˚C) and temperatures (25 (control), 10 and 5 °C at 50 days) in a factorial experiment based on the completely randomized design with three replications and in the second experiment, effect of different nutrition concentrations of MS medium (full strength MS, 1/2MS and 1/4 MS) in a completely randomized design with three replications on embryo culture of four native species of barberry (Berberis integrima, B. vulgaris, B. crataegina and B. orthootrys) were investigated. Based on the results obtained from the first experiment, chilling treated seeds showed the greatest effect (88%) on seed germination in comparison with gibberellic acid treatment. The results of the second experiment showed that the best MS concentration for embryo culture was full strength MS medium with%100 seed germination in four above mentioned barberry species after 2-3 days. In general, the best method to overcome barberry seed dormancy was an embryo culture in full-strength MS nutrition.
