Phosphorus fertilizers – the importance of phosphorus in plant cultivation?

Phosphorus fertilizers are one of the most important elements necessary for the growth and development of plants. In the plant, it performs structural (it is a component of phospholipids), spare (phytin) and regulatory functions in gene expression. Apart from carbon, nitrogen and sulphur, phosphorus also participates in the biochemical transformations and metabolism of the plant both directly (sugar phosphates) and indirectly, regulating the activity of enzymes through phosphorylation and deforylation. Its irreplaceable role in transmitting plant genetic information – as a component of nucleic acids – and storing energy – it builds the ATP and NADPH molecule – should also be mentioned. Phosphorus deficiency is the most dangerous in the initial stages of the plant’s development, as it determines the growth rate of the root system, which is used to extract water and minerals from the soil.

It has also been shown that its content in the soil influences the latter’s microbiological and biochemical activity, which determines the transformation and availability of other plant nutrients. Phosphorus present in the soil is a component of organic (phytic acid) or inorganic compounds, which are typically inaccessible to plants. Phosphorus forms which are readily available to plants include phosphate ions (H2PO4- or HPO42-) present in the soil solution, the content of which is below 10 μM. It is assumed that 80% of the phosphorus taken up by plants is accumulated in seeds or kernels in the form of phytin, which is the primary source of phosphorus for developing seedlings. Plants optimally fertilised with phosphorus are characterised by increased resistance to diseases and water shortages, as well as increased hardiness and higher fat, sugar, protein and vitamin content. Phosphorus reduces the accumulation of harmful forms of nitrogen in plants (eliminates the negative effects of nitrogen fertilisation, increasing its efficiency) and enables the correct, uniform grain filling, as well as seed development and ripening.


  • Maintaining a proper state of phosphorus nutrition depends directly on the phosphorus concentration in the soil. High demand for phosphorus occurs in the initial growth phase, spring vegetation, and the formation and growth of seeds !
  • More than 20% of soils in Poland are significantly phosphorus-deficient!
  • A phosphorus boost required for a wheat yield of about 7 tons-ha-1 is about 28 kg·ha-1!
  • Phosphorus deficiency symptoms in plants include dwarfing and the weakening of roots and lower leaves – the latter take on a red-violet shade while younger leaves turn dark green!