Phosphites are a new formulation of phosphorus that provide phosphorus nutrition to plants while also offering fungicidal action.
Around the world, phosphite-based products have yielded excellent results both in terms of phosphorus nutrition and in the control and prevention of diseases.
Scientists worldwide have recognized that phosphite-based products work effectively both as fertilizers and as fungicides. What, then, is the difference between phosphites (PO3) and traditional phosphates (PO4)?
Phosphites are fundamentally different in nature from phosphates, which are the main component of granular fertilizers. Chemically, these compounds are similar, but phosphate contains one more oxygen atom, which significantly alters their properties and reactivity.
The effect of these two compounds on crops differs significantly, despite their chemical similarity. Phosphates form insoluble compounds in the soil, and only a small portion of the phosphorus is absorbed by plants. When applied to the leaf surface, phosphates are also poorly absorbed by the plant because they do not penetrate the cuticle layer of the leaf surface well.
Phosphite compounds (e.g., potassium phosphites) are usually used in liquid form—as an aqueous solution. Three oxygen atoms increase the mobility of phosphorus in plant tissues and in the soil. They can act on all parts of the plant—leaves, stem, and roots. Phosphites are easily absorbed and transported through the xylem and phloem to all parts of the plant.