Possibility of reducing nitrogen losses with soil fertility preservation in winter wheat cultivation in Poland in relation to the strategy "from farm to fork"

A questionnaire survey was carried out in 1186 farms cultivating winter wheat to det. the yields obtained with the applied rates of mineral N. The uptake, utilization efficiency and losses of N were estd. Regression anal. was performed to det. the relationships between losses, utilization efficiency and applied N rates. N losses at rates greater than 180 kg/ha were approx 19-41 kg/ha, and a 50% redn. in these losses would reduce the applied N rates by 9-20 kg/ha.