Physiological, Biochemical, and Molecular Aspects of Seed Priming

Abstract

Seed priming is a low-cost and effective strategy to enhance seed germination, vigor index, and yield in many field crops mainly under adverse environmental conditions. Seed priming is known to trigger the normal metabolic developments during early stage of germination, before the radicle protrusion. Higher, faster, and synchronized germination of primed seeds largely occurs due to enzyme activation, reduced imbibition time, metabolic reparation during imbibition, buildup of germination-promoting metabolites, and osmotic adjustment. Moreover, plants emerging from primed seeds exhibit faster activation of cellular defense systems, which trigger tolerance against consequent exposure to environmental stresses in the field. Several seed priming approaches including hydropriming, nutrient priming, hormonal priming, chemical priming, osmopriming, and redox priming can be effectively used under different environmental conditions. The present chapter provides an overview of the physiological, biochemical, and molecular changes modulated by seed priming, which enhance seed germination and plant growth. Moreover, it discusses the possible mechanisms associated with seed priming-induced abiotic stress tolerance in plants.