Progress of Research on Seed Priming in Major Field Crops

Seed priming is a pre-sowing technique where seeds are hydrated with solutions of specific osmotic potential for a set period, often with organic or inorganic chemicals at controlled temperatures. This process repairs cell structures, activates enzymes, converts stored materials to energy, and initiates metabolism before germination. Seed priming promotes rapid, uniform germination, dormancy breaking, water and nutrient use efficiency, improved tolerance to environmental stresses, and resistance to diseases. It is an affordable, effective technology that enhances seed performance and early plant development in field crops. Seed priming methods include hydro-priming, halo-priming, hormonal, osmo-, solid-matrix, nutrient, nanoparticle, and bio-priming. Advanced seed priming methodologies such as nanoparticles, gamma-ray, magnetic-ray, and ultraviolet irradiation have prompted concerns regarding their potential adverse effects on plants, human health, and the environment. The optimal treatment differs between species, cultivar, and seed lots. Such variability is a major limitation of the priming method, and hence, numerous trials are required to identify the most appropriate strategy for each situation. Selection of the right priming technique is crucial for realising optimal results with this cost-effective approach and is a valuable technology for sustainable agriculture. The review aims at summarising the seed priming principles, mechanisms, and recent research advances made adopting different methods of seed priming and the beneficial effects of seed priming on morpho-physiological and biochemical characters in major field crops such as rice, wheat, maize, sorghum, greegram, blackgram, pigeon pea, chickpea, groundnut, soybean, sunflower and sesame.