Seed priming as a method of preservation and restoration of sunflower seeds

Abstract

The study focused on determining the preservative and restorative effects of seed priming with gibberellic acid (GA(3)) and potassium nitrate (KNO3) on sunflower seeds against deterioration. The seeds were immersed in different concentrations (0, 250, 500, and 1000 mg L-1) of GA(3) and KNO3 solutions before and after being subjected to accelerated aging (AA). Unprimed seeds (NT) were used as control. The results showed that AA led to a reduction in germination percentage, germination index, and seedling growth parameters. However, seed primed with GA(3) had a higher germination percentage after AA than NT. All seed primings shortened mean germination time and improved germination index. Seedling growth was stimulated by seed priming, and seed priming after AA produced more vigorous seedlings than primed seed before AA because they were severely affected by AA. In addition, hydration sufficiently induced the germination and seedling growth of aged seeds. A significant difference was found between GA(3) and KNO3, and seeds were effectively protected from aging by GA(3), while hydration promoted germination of aged seeds. Consequently, the recovery effect of seed priming was more pronounced than the conservative effect, and sunflower seeds should be primed with 500-1000 mg L-1 GA(3) before storage or, if this is not possible, hydration improves the vitality and subsequent growth of aged sunflower seeds.