Role of Seed Priming in Enhancing Germination under Abiotic Stresses (Drought, Salinity, Heat)

Abstract

Seed germination is a critical stage in a plant’s life cycle and is highly vulnerable to abiotic stresses such as drought, salinity, and high temperature, which can severely impair physiological and biochemical processes. Seed priming a controlled pre-sowing hydration treatment has emerged as an effective strategy to improve seed performance under these unfavorable conditions. This review highlights the mechanisms and benefits of different priming techniques, including hydropriming, Osmo priming, hormonal priming, bio-priming, and nano-priming, in mitigating abiotic stress impacts. Primed seeds exhibit enhanced enzymatic activity, antioxidant defense, osmotic regulation, and hormonal balance, resulting in improved germination, seedling vigor, and stress resilience. Under drought conditions, priming promotes osmotic adjustment and antioxidant capacity; under salinity stress, it maintains ion homeostasis and photosynthetic efficiency; and under heat stress, it stabilizes proteins and activates heat shock responses. Recent advancements such as molecular, nano-, and bio-priming demonstrate the potential to enhance crop tolerance and productivity sustainably. Overall, seed priming represents a cost-effective, eco-friendly, and practical approach to strengthen crop resilience and ensure food security under changing climatic conditions.