Effects of various nitrogen fertilisers applied in autumn on growth parameters, yield and quality of winter oilseed rape

Abstract

The aim of this trial was to verify the influence of various autumn-applied nitrogen fertilisers on the growth, yield and quality of winter oilseed rape. In the three years, small-plot field trials were carried out at the Research Station Červený Újezd (50.0697044N, 14.1659086E). The hybrid cultivar DK Exstorm was chosen, with a sowing rate of 50 seeds/m2. Five fertilisation regimes were tested: (1) nitrogen-free control; (2) CAN (calcium ammonium nitrate); (3) ANU (ammonium nitrate urea); (4) U (urea), and (5) US (urea with N-(n-butyl)thiophosphoric acid triamide (NBPT) inhibitor). A uniform dose of 40 kg N/ha was applied at the end of October. Fertilisers U (leaf length, root collar diameter, leaf and root dry weight) and US (number of leaves and root length) had the best growth outcomes. The highest seed yields were obtained with US (5.83 t/ha) and ANU (5.82 t/ha) applications, which outperformed the unfertilised control by 0.65 and 0.64 t/ha, respectively. CAN fertiliser appears to be unsuitable for autumn fertilisation in terms of yield. There were no statistically significant differences in oil content (%) or thousand seed weight (g) between the treatments in any of the experimental years.

Keywords

• brassica napus l.
• oilseed crop
• mineral nutrient
• autumn nitrogen fertilisation
• dry matter