PIAMON® 33-S - Principle of action

PIAMON® 33-S is a granulated mixed fertiliser that combines the most favourable mixing ratio of ammonium sulphate and urea in a single fertiliser granulate to provide the best possible fertilising effect with respect to N without focusing on the fertilising effect of S. PIAMON® 33-S is thus a product that is distinguished not only by its additional sulphur content. Because of the optimised mixing ratio, it represents an ideal product with respect to its N fertilisation effect.

The combination of the two types of N as ammonium and carbamide nitrogen in PIAMON® 33-S provides an immediate as well as a balanced supply of nitrogen to the plants.

When PIAMON® 33-S is used as the fertiliser, the simultaneous presence of sufficient and immediately assimilable water-soluble sulphur in the soil is an additional advantage for an optimum nutrient uptake. The NH4+ cation and the SO4- anion are not in competition and do not hinder each other with respect to nutrient uptake by the roots. In contrast, the possible charge compensation leads to particularly high and appropriate uptake rates by the plants and, as a consequence, to the above-mentioned extremely high N efficiency of PIAMON® 33-S.
In addition to the active uptake of ammonium N and sulphur as sulphate by the plants and its immediate assimulation into the protein metabolism already in the roots creates a harmonious equilibrium with respect to carbohydrate synthesis in the shoots. According to SOMMER (2000), this optimum type of plant nutrition based on ammonium N with full utilisation of the protein metabolism of the crops taking place synchronously to the intensity of carbohydrate production thus leads to growth conformity. The development of shoots and roots are brought into a harmonious equilibrium with the highest growth potential.

In addition to these insights, it is also known that the type of nitrogen in the soil influences the root formation of the plants. According to RÖMHELD (1986), an ammonium-biased plant nutrition leads to significantly greater formation of secondary roots as well as to a reduction of the pH value in the rhizosphere zone. As a consequence of these processes, the uptake efficiencies of the plants with regard to water and nutrients is improved. In addition, further nutrients, such as phosphorus and micronutrients (e.g. Mn) are mobilised and are also available to the plants.

The very high N efficiency of PIAMON® 33-S compared to calcium carbonate/ammonium nitrate mixtures is due to the positive effects of an ammonium-biased nitrogen nutrition combined with a enhanced root formation and the additional mobilisation of further nutrients as well as to the balanced protein metabolism taking place synchronously to the synthesis of carbohydrates. Because these processes have different intensities, but occur during the entire vegetation period, and because sulphur is an essential component of protein synthesis and other enzymatic processes, the sufficient quantities of sulphate from PIAMON® 33-S that are immediately available to the plants at all fertilisation times has an additional positive effect.