Seed Priming for Abiotic Stress Tolerance in Crop Systems

Seed priming is a pre-sowing technique that exposes seeds to controlled hydration and, in some cases, chemical or hormonal agents, thereby initiating metabolic processes without radicle protrusion. This partial activation enhances germination uniformity, vigour and stand establishment under adverse conditions. Protocols such as hydropriming, osmopriming, redox priming and phytohormonal priming can be tailored to specific stressors—drought, salinity, temperature extremes or nutrient imbalance. At the cellular level, priming stimulates DNA repair, stabilises membranes, modulates antioxidant defence systems and accumulates osmolytes and stress-responsive proteins. It also establishes a form of physiological memory, enabling seedlings to mount a more rapid and robust response when exposed to subsequent stress. As a low-cost, scalable approach, seed priming holds global significance for safeguarding food security and improving resilience of cropping systems in variable climates.

Research from Nature Portfolio

Two foundational studies have clarified the constraints and opportunities of seed priming in rice. The first demonstrated that longevity of primed rice seeds is markedly reduced by storage at ambient temperature, with beneficial effects on germination and seedling growth maintained for only two weeks; cooler storage preserves viability and starch-metabolic capacity, while attempts to re-prime aged seed fail to restore lost vigour. The second investigation examined direct-seeded early rice under chilling stress and revealed that pre-sowing treatments with selenium or salicylic acid significantly enhanced emergence rate and seedling biomass. Improved performance was linked to elevated α-amylase activity, higher soluble sugar content and increased respiratory metabolism, underscoring the role of metabolic priming in cold tolerance.

Seed Priming for Abiotic Stress Tolerance in Crop Systems publication trend

The graph below shows the total number of articles in seed priming for abiotic stress tolerance in crop systems across all publications each year (not limited to Nature Index journals).

Technical terms

Hydropriming: Soaking seeds in water to initiate metabolic activation without visible germination.
Osmopriming: Treatment of seeds with osmotic solutions (e.g. polyethylene glycol) to control water uptake and precondition stress-adaptive pathways.
Redox priming: Application of oxidising or reducing agents (e.g. hydrogen peroxide, neutral electrolysed water) to modulate reactive oxygen species signalling.
Phytohormonal priming: Use of plant growth regulators (e.g. salicylic acid, gibberellins) to influence hormone-mediated stress responses prior to sowing.
α‐Amylase: Enzyme that hydrolyses stored starch into sugars, supplying energy during seed germination.
Reactive oxygen species (ROS): Signalling molecules such as hydrogen peroxide that, in excess, cause oxidative damage but also regulate defence mechanisms.
Na+/H+ antiporters: Membrane transporters that extrude sodium in exchange for protons, crucial for ion balance under saline conditions.

References

1. In vitro assay of neutral electrolyzed water against Fusarium oxysporum and its application as germination pretreatment on tomato (Lycopersicon esculentum), lettuce (Lactuca sativa L.) and cucumber (Cucumis sativus) seeds.. Energy Nexus (2023).
2. Efficacy of seed priming strategies for enhancing salinity tolerance in plants: An overview of the progress and achievements. Plant Stress (2023).
3. Benefits of rice seed priming are offset permanently by prolonged storage and the storage conditions. Scientific Reports (2015).
4. Pre-sowing Seed Treatments in Direct-seeded Early Rice: Consequences for Emergence, Seedling Growth and Associated Metabolic Events under Chilling Stress. Scientific Reports (2016).