Silicon is the second most abundant element in the Earth's crust (behind oxygen), but only a limited amount of silicon is in a form that plants can take up. Current agriculture practices far outpace the natural silicon production cycle necessary to keep up with today’s challenges. Critically, modern agricultural research now emphasizes the value and benefit of silicon to soil and plant health.
Optimal silicon concentrations in plants enhance their resilience, as silicon is used internally and incorporated into epidermal structures like trichomes and silica cells. Recognizing silicon deficiency in plants is complex. Unlike nitrogen or calcium deficiencies, which show visible symptoms, silicon deficiencies manifest subtly with reduced vigor and quality, making early-season silicon fertilization essential to maximizing crop performance and resilience against environmental stressors.
Nutrients that are present in concentrations above 1,000 ppm (0.1%) are considered macronutrients and contain the primary nutrients N, P, K, and secondary nutrients Ca, Mg, and S. Micronutrients are present in concentrations typically below 100 ppm (0.01%) and include B, Cu, Fe, Mn, Mo, and Zn.
The majority of plants accumulate silicon as a macronutrient, above 0.1%, with many accumulating above 1% silicon (within the values of nitrogen). There are plants that have lower silicon concentrations in their leaves, but still benefit from silicon, especially during stress.
Major agronomically important crops with reported silicon-enhanced tolerance to leading yield-loss causing environmental stresses. Marked entries indicate confirmed stress tolerance based on available literature, while blank fields denote areas not yet tested or reported.
