Effect of ridge film mulching and nitrogen application rate on seed quality, oil yield and nitrogen-use efficiency of winter oilseed rape in northwest China

Abstract

ABSTRACT Three-year field experiments were conducted to investigate the effects of ridge film mulching plus furrow planting (RFMF) and traditional flat planting (FP) on the seed quality, oil yield and nitrogen-use efficiency of winter oilseed rape (Brassica napus) and to determine the optimal rate of nitrogen (N) application under the two planting patterns. Six N rates, 0, 60, 120, 180, 240 and 300 kg N ha−1, were applied under both patterns. RFMF significantly increased seed yield, oil yield, N agronomic efficiency (NAE) and N partial factor productivity (NPFP) by 15.5–43.5%, 18.0–48.3%, 2.1–70.6% and 17.9–48.2% respectively, compared with FP. The optimal N application rates were 235 and 218 kg N ha−1 under RFMF and FP, respectively. In conclusion, RFMF could be adopted with N rate of 235 kg N ha−1 for the cultivation of winter oilseed rape in northwest China to improve shoot nutrient uptake, oil yield and N use efficiencies.