Iranian Journal of Seed Research

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.

The percentage and rate of germination and proper establishment of seedlings are important factors contributing to higher yield per unit area. As an essential element for plant growth and development, Zinc plays a critical role in many metabolic processes, and also has a positive effect on seed germination. The effects of seed priming with concentrations of 0.5, 1 and 2 percent zinc sulfate on the partitioning of reserved materials in seed, the start of autotrophic seedling growth and the activity of alpha-amylase enzyme were investigated in wheat seeds, using a factorial experiment in the Research Farm of the University of Maragheh, Iran in 2014 on the basis of a completely randomized design with four replications. The results showed that zinc priming had a significant effect on all the parameters under investigation. Mean comparisons showed that an increase in zinc concentration- up to one percent- had a positive effect on the parameters investigated and increasing its concentration more than one percent caused a negative effect on the parameters touched upon above. The results of this study showed that the dry seed weight of the control and zinc sulfate (0.5%) treatment reached a stable level on day 21 and 20, respectively. In addition, in the control and 0.5% zinc sulfate, the total dry weight reached its initial weight (seed weight) on day 15 and 13, respectively. In addition, the growth of autotrophic plant began 10-12 days after soaking. The seeds treated with 5.0 and 1 percent zinc sulfate had more leaf area than the other treatments; this could be due to the earlier entrance of the seedlings produced by 5.0 and 1% zinc sulfate treatments into the autotrophic stage, as compared with other treatments. The results of variance analysis of the finishing seeds' reserved materials, initial kernel, root dry weight and shoot dry weight confirmed that 0.5 and 1% zinc sulfate treatments were better than other concentrations. The treatments of 0.5 and 1%  of zinc sulfate reached the autotrophic stage sooner than the control and 2% zinc sulfate treatment. Given the results of this study, 5.0 and 1% zinc sulfate treatments were selected for field cultivation.