Benefits of Silicon
The precise role on silicon in plants are still being researched and developed, but generally speaking, silicon has been shown to: (1) increase leaf chlorophyll content and plant metabolism
The precise role on silicon in plants are still being researched and developed, but generally speaking, silicon has been shown to: (1) increase leaf chlorophyll content and plant metabolism, (2) enhance plants tolerance to environmental stresses such as cold, heat, and drought, (3) mitigate nutrient imbalance and metal toxicity in plants, and (4) reinforce cell walls, increase plants mechanical strength thereby protecting plants against pathogens and diseases. Studies have shown in early 20th century that plants with applications of silica fertilizer supplements are less prone to attacks and pressures of insects and diseases such as: powdery mildew on cereal, Hessian fly on wheat, and stem borers on rice. In the past 30 years, more research has been done and applications of silicon fertilizers have further shown to ward away diseases on rice such as: blast (Magnaportha grisea), brown spot (Cochliobolus miyabeanus), sheath blight (Thanatephorus cucumeris), and leaf scald on rice (Monographella albescens). As well as, powdery mildew (Sphaerotheca fulginea), damping-off (Pythium), root rot (Fusarium oxysporum), Botrytis blight (Botrytis cinerea), and black mold (Colletotrichum gloeosporioides) in fruit and vegetable crops.
Probably the most notable effect from applying silica through fertigation systems is the balancing of nutrient uptake in the growing media. Most times through frequent application of fertilizers in container mediums and organic compounds released by the roots, the medium becomes incredibly acidic (<5.0) and the growing medium loses its buffering ability and its cation exchange capacity (CEC) which dictates when and what elements are absorbed by plants. Once pH reaches this level, aluminum (Al) and manganese (Mn) become increasingly available over other elements in the soil. Through addition of potassium silicate fertilizer supplements, availability of aluminum, which is phytotoxic to plants, is reduced showing a reduction from 150 ppm in control groups to merely 41 ppm in groups with silica supplements added. Aluminum uptake reduction can be from 3 things: (1) increased pH after applications of silica resulting in the plant prioritization of macro- and secondary elements, (2) silicon ability to bond to aluminum hydroxide (AlOH) which impairs aluminum mobility, and/or (3) the bonding of mobile aluminum onto silicon-based compounds.
Excess of manganese becomes translocated to the shoots resulting in manganese toxicity notably shown through dark, necrotic spots on the leaves caused by an accumulation of manganese oxides (MnO). Silicon mitigates manganese toxicity by the homogenous distribution of the manganese oxides and prevents accumulation of manganese in any one place in the plant. One of the great benefits of applying silica supplements is that silicon can balance nutrient elements in plant tissue through suppression of Al, Mn, and Na, and by mediating the uptake of other essential elements such as P, Mg, K, Fe, Cu, and Zn.
Silicon application improves plant growth by balancing nutrient uptake, transport and distribution in plants, and by enhancing the resistance of plants to diseases. Through frequent application of silicon-based fertilizer supplements, soil is less likely to be acidic, heavy metals are bound reducing heavy metal leaching into the plant, and dry weight of silicon responsive plants can increase upwards of 80% compared to plants that were not given silica supplements.