The investigation was conducted within 2010–2014 on the experimental site of the Maize Research Institute in Knezha on typical black soil (chernozem). A significant increase of the crop yield was established due to the influence of the mineral fertilization and to a lesser degree – as a result of the applied system of soil cultivation. The grain yield in the fertilized options increased from 42.37% to 44.22%, of crude protein (СP) – from 42.59% to 44.28% and of crude fats (СF) from 24.59% to 29.41%. The higher grain yield, СP and СF were received with А1 system from all tested soil cultivation systems for the conditions of the experiment. The applied soil cultivation systems did not influence the values of pH. Regarding the depth of the soil profile, the higher values in layer 0-40 cm of alkali hydrolysable nitrogen and mobile phosphorus were recorded with system А1, and of mobile potassium – with system А2.
Impact of the soil cultivation system and mineral fertilization on the productivity of four-field crop rotation and the agrochemical properties of the soil