Abstract
This article presents the results of a three-year experiment involving a multi-criteria evaluation (productivity, economic and energy balance) of the effectiveness of nitrogen (N) and sulfur (S) fertilization in different cultivars of winter oilseed rape (open-pollinated, semi-dwarf hybrid, long-stem hybrid) grown in north-eastern (NE) Poland. The yield of the semi-dwarf cultivar was 11% lower than the yield of the long-stem hybrid cultivar and 18% higher than the yield of the open-pollinated cultivar. In all cultivars, N fertilization improved yields up to a rate of 180 kg ha−1 and up to a rate of 230 kg ha−1 in years with low precipitation in spring and summer. Seed yield increased in all cultivars in response to S fertilization at 40 kg ha−1. Higher rates of N fertilizer decreased the content of crude fat and glucosinolates (GLS) and increased the concentration of total protein in all cultivars. Sulfur fertilization increased the content of total protein (in long-stem cultivars) and GLS (in all cultivars). Production costs ranged from €542−624 ha−1 (≤130 kg N ha−1) to €619−697 ha−1 (≥180 kg N ha−1). The demand for energy in the production of winter rapeseed ranged from 14.5−19.3 GJ ha−1 (≤130 kg N ha−1) to 22.4−27.0 GJ ha−1 (≥180 kg N ha−1).