LAUSR

The aim of a two-year field experiment conducted in north-eastern (NE) Poland was to evaluate the effect of meat and bone meal (MBM) applied without or with mineral nitrogen (N) on seed yield, thousand seed weight (TSW), protein yield, fat yield, fatty acid profile and glucosinolate (GLS) concentrations in winter oilseed rape. Five treatments were compared: MBM applied at 1.0, 1.5, 2.0 Mg ha−1, inorganic NPK, and a zero-N check. The first two MBM plots and the NPK plots received supplemental inorganic N to provide a total of 158 kg N ha−1. The yields of winter oilseed rape were highest in the treatment with mineral (NPK) fertilization. All plots receiving MBM yielded equally to each other but greater than the unfertilized check. Winter oilseed rape accumulated significantly more protein in seeds in the NPK treatment than in the 1.5 Mg ha−1 MBM + 40 kg N ha−1 treatment. The crude fat content of seeds was significantly higher in the 1.5 Mg MBM ha−1 + 40 kg N ha−1 treatment, compared with the NPK treatment and the 1.0 Mg MBM ha−1 + 79 kg N ha−1 treatment. Oleic, linoleic, and α-linolenic acids accounted for nearly 90% of total fatty acids in rapeseed oil, and the average ratio of linoleic acid to α-linolenic acid was 1.81:1. Fertilization had a minor influence on the proportions of fatty acids, which were considerably affected by adverse weather conditions.