Journal of Experimental Agriculture International

Reliable germination and uniform seedling emergence are important for sunflower (Helianthus annuus L.) establishment, particularly under variable temperature, moisture and soil conditions. Seed priming involves controlled hydration before sowing, followed by drying, to initiate preparatory metabolic processes without allowing radicle emergence. This review examines hydro-priming, osmo-priming, hormonal and chemical priming, and bio-priming, with emphasis on germination behaviour, seedling vigour, physiological responses and practical application. The reviewed studies indicate that priming can shorten germination time, improve emergence uniformity and support early root and shoot development, although responses differ among hybrids, seed lots and stress environments. Hydro-priming is comparatively simple and inexpensive, whereas osmotic and chemical treatments provide additional options for managing water uptake and specific stress conditions. Experimental findings discussed in the manuscript include improved sunflower performance following hydro-priming for 12–18 hours and osmo-priming with polyethylene glycol under water deficit. A field study of gibberellic acid priming at 100 ppm for 12 hours reported 88.94% field emergence and 29.95 g seed yield per plant under its experimental conditions. Potential physiological responses include changes in membrane integrity, antioxidant activity and metabolic regulation. Practical constraints include excessive hydration, microbial contamination and reduced storability after treatment. Overall, priming should be evaluated for individual seed lots and environments rather than treated as a universally effective procedure. Further multi-location field studies are needed to clarify the consistency of its agronomic benefits.