Silicon Applications in Plant Stress Tolerance

Silicon, although not classified as an essential nutrient, has emerged as a critical mediator of plant resilience under a range of environmental stresses. Uptake of soluble silicic acid leads to deposition of amorphous silica (phytoliths) within cell walls, where it fortifies mechanical barriers and mitigates pathogen ingress. Beyond this structural role, silicon modulates physiological and molecular responses to drought, salinity, heavy metals and oxidative stress. It enhances antioxidant defence systems, reduces reactive oxygen species accumulation, and stabilises membranes under water deficit. In saline conditions silicon limits sodium influx and promotes selective ion homeostasis. By influencing the expression of transporters and stress-responsive genes, silicon orchestrates osmotic adjustment, improves water uptake through aquaporin regulation, and maintains nutrient balance. Ongoing research underscores its dual action as both physical protectant and biochemical signaler, with implications for sustainable agriculture and crop productivity in marginal soils worldwide.

Research from Nature Portfolio

Recent studies have identified a silicon transporter gene in rice that is indispensable for correct cell-specific silicification and normal growth. Loss of this transporter causes mislocalised silica deposition in mesophyll cells, triggers widespread stress-related gene activation and leads to plant death in silicon-rich environments. This work reveals the importance of precise silicon export to the leaf surface for stress tolerance and developmental integrity. Complementing these findings, advances in spectroscopic analysis have enabled differentiation among amorphous silica, short-range-ordered silicates and dissolved silicic acid species. Improved resolution of silicon phases in soil and plant tissues offers new insights into silicon bioavailability, ecosystem nutrient cycles and the mechanisms by which specific silicon compounds influence plant water status and resistance to abiotic stress.

Silicon Applications in Plant Stress Tolerance publication trend

The graph below shows the total number of articles in silicon applications in plant stress tolerance across all publications each year (not limited to Nature Index journals).

Technical terms

Phytolith: Amorphous silica deposit within plant cell walls that enhances structural rigidity and defence.

Reactive oxygen species (ROS): Highly reactive oxygen-containing molecules that can damage proteins, lipids and nucleic acids under stress.

Aquaporin: Membrane channel protein facilitating regulated water transport across cell membranes, crucial for drought tolerance.

Silicification: Process of silica deposition in plant tissues, contributing to mechanical strength and stress protection.

References

1. A silicon transporter gene required for healthy growth of rice on land. Nature Communications (2023).
2. Comparing amorphous silica, short-range-ordered silicates and silicic acid species by FTIR. Scientific Reports (2022).
3. Aquaporin-mediated increase in root hydraulic conductance is involved in silicon-induced improved root water uptake under osmotic stress in Sorghum bicolor L.. Journal of Experimental Botany (2014).
4. Silicon Regulates Antioxidant Activities of Crop Plants under Abiotic-Induced Oxidative Stress: A Review. Frontiers in Plant Science (2017).
5. The Role of Silicon in Higher Plants under Salinity and Drought Stress. Frontiers in Plant Science (2016).
6. Interactions of Silicon With Essential and Beneficial Elements in Plants. Frontiers in Plant Science (2021).
7. Role of Silicon on Plant–Pathogen Interactions. Frontiers in Plant Science (2017).
8. Silicon and the Plant Extracellular Matrix. Frontiers in Plant Science (2016).