The influence of liming and mineral fertilization on the content of various nitrogen forms in spring barley

The aim of the experiment was to find out the influence of liming and fertilization with ammonium sulphate and calcium nitrate on the content of total protein, true protein, N-NO3 and N-NH4 in spring barley. The study was based on the chemical analysis of plant material obtained from a two-year pot experiment. The factors of the study were: liming fertilization with ammonium and nitrate nitrogen at two levels and fertilization with phosphorus at two doses. The obtained results indicated that the content of total protein and true protein was higher in plants fertilized with ammonium sulphate than in plants fertilized with calcium nitrate. Liming caused a decrease of protein content in the tested plant. The content of ammonium and nitrate nitrogen in the plant was lower in limed than non-limed combinations. Ammonium sulphate influenced a significant increase of the content of N-NH4 whereas calcium nitrate caused an increase of the concentration of N-NO3 in spring barley.