Nitrogen in plant nutrition

Nitrogen (N) is the principal nutrient for crop production. It makes up 2 to 4% of plant dry matter and ranks as the most abundant mineral nutrient in their composition^[1]. As an essential component of proteins and chlorophyll, it determines vigour, green colouration, tillering, leaf production, organ expansion and yield formation^[1]. Cultivated species absorb it in two ionic forms: ammonium (NH4+) or nitrate (NO3-), except for legumes which can fix atmospheric nitrogen^[1].

Physiological functions and mobility

Within the plant, nitrogen performs irreplaceable functions. It contributes to the formation of amino acids, amides and proteins, and plays a part in the transport of assimilates through the phloem^[1]. Its mobility in plant tissues enables reallocation from older leaves to developing organs during deficiency, resulting in early yellowing of lower plant parts^[1]. Nitrogen supply directly affects agricultural product quality: intensive fertilisation, for instance, improves the bread-making characteristics of cereals but may reduce the average protein value of grain^[2]. Foliar nitrate, meanwhile, increases under nitrate fertilisation, notably in leafy vegetables for human consumption and in fodder beet tops^[2].

Share of fertiliser consumption and market structure

Nitrogen dominates global nutrient consumption with 58% of the total, compared with 24% for phosphorus and 18% for potassium^[3]. This share stood at 54% according to earlier 2022 estimates^[4][3]. The nitrogen market is markedly fragmented: nitrogen fertilisers are manufactured in numerous countries, with natural gas and air as widely available feedstocks^[3][4]. By contrast, phosphate and potash markets show high concentration, as phosphate rock and potash mineral deposits are geographically restricted^[3][4]. The leading nitrogen fertiliser producer groups include CF Industries, Yara, Nutrien, EuroChem, OCI and Fertiglobe^[5].

Agronomic requirements and supply management

Unlike phosphorus and potassium, which soils can fix and store across several seasons, nitrogen requires annual renewal to maintain yield and biomass^[3][4]. This characteristic gives the nitrogen market relatively stable volumes despite price volatility^[3]. Cereals (wheat, rice, maize) take up roughly half of global fertilisers; maize alone accounts for 20% of total nitrogen consumption, followed by wheat (18%) and rice (16%)^[6][7]. Fruit and vegetables represent 12% of nitrogen use^[6]. Nitrogen management raises environmental concerns: nitrate leaching and ammonia volatilisation constitute the main loss pathways, whilst nitrous oxide has emerged as a major greenhouse gas from the agricultural sector. Precision techniques — nitrification inhibitors, urease inhibitors, controlled-release fertilisers — aim to improve nitrogen use efficiency and reduce these impacts^[2].

Nitrogen fertiliser forms and supply routes

The industry offers several nitrogen product families. Anhydrous ammonia (NH3), produced by the Haber-Bosch process, serves as feedstock for the entire chain. Urea dominates international trade through its high nutrient concentration. Ammonium nitrates and UAN solutions provide readily assimilable nitrate nitrogen. Ammonium sulphate and calcium ammonium nitrate (CAN) offer nitrogen-sulphur or nitrogen-calcium combinations. Phosphate fertilisers DAP and MAP also incorporate nitrogen into binary or compound NPK fertiliser formulations. The choice between ammoniacal nitrogen, nitrate or ureic nitrogen depends on crop stage, soil type and climatic conditions.