EFFECT OF WINTER WHEAT TILLAGE METHODS ON NITROGEN FERTILIZER EFFICIENCY

At the Pawlowice Experimental Station belonging to Wroclaw University of Environmental and Life Sciences four year field studies were carried out. Three tillage system was compared: traditional (TT), no-tillage into stubble (NS) and bicropping - no-tillage on white clover living mulch (NWC). The measurements grain, protein and energy yields allowed us to determine the efficiency of nitrogen uptake. The efficiency of N fertilizer was determined in relation to yield given in metrical units and also protein and energy yields noted on various harvest dates. Grain yield was 56.5% higher on a traditional tillage than from no-tillage system and 85.7% higher than from bi-cropping system. The most effective N fertilizer efficiency was found with a traditional tillage system, since the increases observed in grain yield were the greatest. NWC system reduced nitrogen fertilization efficiency expressed in each parameter determined. The white clover at NWC could have influenced the nitrogen availability and efficiency of biological nitrogen resources.