Redox priming of seeds to ameliorate salinity tolerance in plants

Burgeoning demands for food with rapid increases in world population warrants the need for developing strategies to utilize marginal lands and saline resources for agricultural production. Seed redox priming can be an easy, effective, and cost-effective way to improve not only the germinability of seeds but also the tolerance of seeds and seedlings to common abiotic stresses such as salinity. Redox priming involves controlled hydration of seeds in the solution of a redox compound that induces a number of metabolic activities before radicle emergence, thereby preparing seeds for a head-start to germinate as well as enhancing overall stress tolerance during germination and seedling growth. Hydrogen peroxide, nitric oxide, ascorbic acid, tocopherol, and glutathione are commonly used agents for redox priming. Such studies are mostly confined to crop seeds, and this information about the seeds of many newly emerged crops, including resistant halophytic crop candidates, is scant. This chapter attempts to provide an overview of the research on redox seed priming and also highlights the gaps in knowledge in this regard.