Molecular mechanisms underpinning the silicon-selenium (Si-Se) interactome and cross-talk in stress-induced plant responses

The global agriculture system remains vulnerable to several kinds of spatio-temporal abiotic and biotic stressors. At the molecular and physiological levels, the elimination of challenges associated with these stressors in plants has been intensively explored. The plants appear to have evolved with a multitude of physio-biochemical survival strategies, including a central signaling cross-talk channel that allows the plant to arbitrate between active growth and defensive pathways. Furthermore, exogenous administration of micronutrients such as silicon (Si) and selenium (Se) has been shown to improve plant defense responses under stressful situations. These micro-nutrients exhibited a large number of physio-biochemical responses throughout various plant systems and were found associated with pathways of stress signaling cross-talk. Several studies had provided pieces of evidence for the potential role of Si/Se in the induction of phytohormonal and anti-oxidant stress signaling mechanisms. Except for greater Se-toxicity at low concentrations when compared to Si, the individual and combined effects of Si/Se in many plants have shown similar induction routes. However, the effectiveness of Si/Se levels in different plant species differs greatly. A vast number of omics studies are currently being conducted in order to determine the exact molecular mechanisms through which Si/Se activation of the defense response could well be understood. This review aims to uncover the possible molecular convergent points for Si and Se actions as well as their potential cross-talk with stress signaling mechanisms.

Automated summary

The global agriculture system is susceptible to various stressors, and plants have evolved different strategies to cope with these challenges. Adding micronutrients like silicon and selenium has been shown to improve plant defense responses, but their effectiveness varies among different plant species.