Breaking Barriers: Selenium and Silicon-Mediated Strategies for Mitigating Abiotic Stress in Plants

Abstract

Numerous plant species, particularly those that can accumulate selenium (Se) and silicon (Si), benefit from these essential micronutrients. Se and Si accumulation in plants profoundly affects several biochemical reactions in cells. Understanding how plants react to Se/Si enrichment is crucial for ensuring adequate dietary Se/Si intake for humans and animals and increasing plant tolerance to environmental stressors. Several studies have shown that Se/Si-enriched plants are more resistant to salinity, drought, extreme temperatures, UV radiation, and excess metalloids. The interplay between Se/Si in plants is crucial for maintaining growth and development under normal conditions while providing a critical defense mechanism against stressors like heavy metals and drought. Se and Si commonly stimulate antioxidant defense systems in plants exposed to environmental stressors, but the involved mechanisms are complex and not well understood. To ensure the positive effects of Se/Si fortification in plants, it is essential to consider the degree of accumulation, the chemical form of Se/Si used, the method of application, and the likelihood of interaction with other elements. In this review, we will discuss the effects of Se/Si bio-fortification on plants subjected to abiotic stressors. Plant responses to exogenous Se/Si will also be reviewed, emphasizing the influences of Se/Si in the modulation of enzymatic and non-enzymatic antioxidant defense mechanisms under various abiotic stress conditions.