EN
The objective of this research project was to determine the effect of multi-component fertilizer application on dry metter yield, floristic and chemical composition of pasture sward. Investigations were carried out on a permanent pasture in Brody. The following ten multi-component mineral fertilizers of different composition were used: Agro 10, CAN 27, Hydrofoska 16, Hydrofoska 21, Kemira Power 16, Kemira Power 5, Kemira NPK 5, Lubofos 12, Viking 13, Viking + (14). For comparative purposes, the ammonium nitrate 34% was also applied. Chemical composition and acidity of the pasture soil as weil as the latest yields were the factors which decided on establishing the single fertilizers dose at the level of 60 kg nitro gen, 8 kg P and 30 kg K per hectare. In the course of planned quadruple application of sward fertilization during vegetation season, the pasture was to receive the total of 240 kg ha⁻¹ N, 32 kg ha⁻¹ P and 120 kg ha⁻¹ K. The point of reference in fertilizer application was the volume of a single nitrogen dose. The lacking quantities of potassium and phosphorus, which could not be introduccd in a dose of multi-component fertilizers, were supplemented in form of potash salt and superphosphate. The only exception was the fertilizer combination with Lubofos 12 being referred to phosphorus and the lacking quantity of nitrogen was introduced in ammonium nitrate. Evaluation criteria of fertilization comprised the dry matter yield of sward regrowth as weil as its floristic and chemical composition. Attention was also paid to chemical properties of soil. Results of our investigations allowed to conclude that multi-component fertilizers changed the pasture floristic sward composition towards grass domination and reduced the proportion of legumes and herbs. However, their effect in this respect was found smaller than that of traditional fertilizers - ammonium nitrate in combination with superphosphate and potash salt. The response of grass species to nutrient available in multi-component fertilizers varied. Hydrofoska 21, CAN 27 Kemira and Kemira Power 5 increase of Lolium perenne proportion in the pasture sward. On the other hand, Poa pralensis was less demanding as regards the form of the applied fertilizer. The application of the multi-component fertilizer, allowed to obtain the yield of sward regrowth corresponding to that obtained with traditional fertilization. Viking 13 and Lubofos 12 turned out more effective in influencing yields than other examined multi-component fertilizers. Multi-component fertilizers allowed to obtain sward of similar nutritive value to that produced with the aid of traditional mineral fertilization. Multi-component fertilizers applicd systematically can modify favourably the content of phosphorus, potassium and magnesium in the soil. The factor, which will decide about a wider range of application of multi-component fertilizers in pasture fertilization, is the economics. It is very important to undertake investigations in this field as soon as possible.