The Role of Zinc Sulfate and Potassium Nitrate on Seed Germination Parameters Improvement of Black Cumin (Nigella sativa) Medicinal Plant

In order to investigate the effect of priming techniques on germination parameters of black cumin (Nigella sativa L.), sixteen seed priming treatments, including control (no priming), three hydropriming levels with distilled water (24, 36, and 48h), three osmopriming levels with PEG (solutions with osmotic potential of -4, -8 and -12 bar), three hormonepriming levels with GA3 (50, 100 and 150 ppm) and three halopriming levels with KNO3 solution (2, 3, and 4%) and three zinc sulfate levels (0.1, 0.3 and 0.5%), was conducted through a completely randomized design with four replications. The results showed that the maximom germination rate was observed with KNO3 2% and ZnSO4 0.5%, respectively. Seed priming treatment nether improve germination percentage, radicle and shoot dry weight and radicle and shoot length than control, nor decrease significantly some of them. Polyethylene glycol, GA3 and hydropriming didn’t affect the germination improvement of black cumin, however KNO3 2% and ZnSO4 0.5% treatments were effective on germination rate and seed vigor. In conclusion, seeds treatment with ZnSO4 0.5% and/or KNO3 2% could be recommended to improve the black seed germination in field conditions.