results of fertilization of winter oil seed crop using nitrogen

The influence of fertilization using the CULTAN (Controlled Uptake Long Term Ammonium Nutrition) method on winter rape yield, content of dry matter in aboveground biomass, and nitrogen content in seed was studied in 2008–2009 in small-plot experiments at three different soil-climatic sites. Plants with CULTAN treatments were fertilized once in spring with a whole dose of nitrogen injected into the soil. Plants with conventional treatments were fertilized using the system of three divided doses applied on the soil surface. The overall dose of nitrogen was 200 kg N ha–1 in each treatment. In 2008, the seed yield at CULTAN treatments compared to that at conventional treatments was by 0.8 t ha–1 lower on the average at sites ??slav and Humpolec. In 2009, no significant differences in seed yield between the two systems of fertilization were observed. Higher dry matter content in aboveground biomass at CULTAN treatments was observed in 2008 at sites ??slav and Humpolec. Significantly lower nitrogen content in the seed at CULTAN treatments was observed at all sites in 2008.