Effects of nitrogen fertilization on yield and grain quality in malting barley

The aim of this study was to investigate the effect of different nitrogen rates on the yield and physicochemical properties of four malting barley genotypes (Kristal, Premijum, Novi Sad 519 and Novi Sad 525). Three-year trials (2008 to 2010) were carried out on the non-calcareous smonitza soil type. The following nitrogen rates were applied: 50, 70, 90 and 110 kg ha super(-1). Obtained results show that nitrogen significantly increased the grain yield (2219 to 2987 kg ha super(-1)). Grain quality was decreased by increasing nitrogen rates (1.24 to 2.13%). Apart from nitrogen rates, the genotype also affected the yield. Premijum variety gave the highest grain yield and the lowest protein content. The optimal plant nutrition was achieved by applying 50 kg N ha super(-1). By further increasing nitrogen amounts, the grain yield increased from 380 to 769 kg ha super(-1), but the differences were not significant. Different nitrogen rates showed a significant effect on the absolute grain weight (3.00 to 5.76 g) and volume grain weight (2.22 to 5.28 kg hL super(-1)).