Hydrogen peroxide priming promotes salinity tolerance in plants—A comprehensive review

Abstract

Salinity stress is a growing concern for agriculture, as soil salinization is increasing worldwide and seriously affects global agricultural production and food security. How to minimize the adverse effects of salinity stress and meet the food needs of the growing human population becomes an urgent problem. Conventional techniques in agriculture and recently modern plant science have limitations; therefore, alternative technologies such as hydrogen peroxide (H2O2) priming have emerged as promising solutions. The findings highlight that H2O2 priming enhances antioxidant defenses, regulating the balance between reactive oxygen species production and scavenging. Furthermore, H2O2 priming promotes osmotic adjustment by stimulating the accumulation of osmoprotectants, maintaining cellular water status under salinity conditions. The review also discusses how H2O2 priming modulates gene expression and signaling processes, causing stress‐responsive genes and transcription factors activation. Moreover, H2O2 priming helps to preserve chloroplast integrity and photosynthetic efficiency, mitigating the detrimental impacts of salt stress on plant development and productivity. Overall, the collective knowledge gathered here, covering various aspects of the H2O2 priming phenomenon, may facilitate the design and conduct of future research on plant tolerance to salinity or other abiotic stresses. However, future research needs to focus on elucidating how priming can be applied on a large scale to diverse plants, understanding biochemical and molecular mechanisms of H2O2 priming for precise and reliable applications of this approach, and figuring out the potential benefits of in vitro priming (H2O2) technology in plant science.