Silicon Availability Affects the Stoichiometry and Content of Calcium and Micro Nutrients in the Leaves of Common Reed

Although silicon is not an essential element in sensu stricto for plant growth, it affects plant stress resistance and may affect the composition of cell wall compounds, especially of grasses. Where silicon availability alters the stoichiometry of macro nutrients in grasses, data on the interaction with calcium and micro nutrients are rare and hence are focussed on in this study. The effect of silicon availability on calcium and micro nutrient content of the leaf blades of common reed, Phragmites australis, were assessed in a pot experiment with three levels of silicon supply. Calcium and micro nutrient concentrations and stoichiometry in leaf blades is altered by changing silicon availability during plant growth. In addition, Scanning Electron Microscopy (SEM) reveals that elevated silicon supply promotes silica deposition and changes the element content of micro and macro nutrients in the near epidermis tissue of P. australis leaves. Silicon availability has a major impact on calcium and micro nutrient content and stoichiometry in grasses. This in turn may considerably affect the nutrient cycling in grass dominated ecosystems.