Phosphorus in rocks, minerals and organic substances breaks down and becomes free, and the plant benefits from these free phosphorus compounds. However, phosphorus is generally found in the soil in bound form that plants cannot benefit from. Especially in soils with high pH, calcareous content or high magnesium, it precipitates by forming insoluble compounds as calcium phosphate or magnesium phosphate, and plants cannot benefit from this structure. The plant's utilization rate of phosphorus from fertilization is around 30%. We can ensure the effectiveness of phosphorus given by fertilizers or available in the soil by lowering the pH.

Plants can easily absorb free phosphorus in the soil. Phosphorus is used mostly in the young period of plants. Phosphorus use increases relatively during the seed period.

Phosphorus is absolutely necessary for issues such as flowering biology, seed formation, energy transfer (ATP), and gene transfer (DNA).

Phosphorus deficiency causes most of the plant's generative damage. Phosphorus deficiency manifests itself primarily in old leaves (mobile). In case of deficiency, the leaves first turn dark green, then blue green, and then red and red-purple.

In excess of phosphorus or excessive phosphorus fertilization, it prevents the uptake of iron (Fe +2 ), zinc (Zn +2 ), calcium (Ca +2 ), boron (B) and manganese (Mn +2 ).

Uptake Forms of Phosphorus: H 2 PO 4 and HPO 4 -2

• Energy transfer (ATP) is effective in transporting and storing substances such as sugar and starch.
• It takes part in the formation of nucleic acids (DNA) and gene transfer.
• It is important in flower and fruit formation and root development.
• It is essential for cell division and formation of new cells.
• It regulates the growth of my meristem tissues.

• Lifeless, weak and soft flower formation.
• Leaves turning first dark green, then blue green, and then red and red-purple (anthocyan accumulation).
• Weakening of the roots, lifelessness and lack of absorbent hairs.
• Shortening, thinning and threadlike development in the shoots, narrowing between the nodes.
• In addition to the formation of small and misshapen fruits, it causes a decrease in the number of seeds, seed development disorders and a shortening of the shelf life.

• Soils with a pH lower than 5.5 or higher than 7.5.
• Soils with high clay content.
• Soils with low organic matter content.
• Presence of phosphorus completely bound in the soil
• Soils high in aluminum or iron hydroxide