Effects of Fertilization and Cropyears on Maize (Zea mays L.) Yields in Different Crop Rotations

Four basic elements of crop management of maize production — crop rotation, fertilizer application, irrigation and population density — were studied on chernozem soil in long-term experiments. The weather in all the three years (2004, 2005 and 2006) studied was basically favourable both as regards water supply and temperatures. In the critical phenophase (tasseling and silking in July), however, due to the precipitation amounts differences could be found. In years with favourable water supplies it was the crop rotation and fertilizer application that basically determined maize yields whereas irrigation and population densities did not have significant effects. According to our long-term experimental results we can state that we have to harmonize the key-agrotechnical elements (crop rotation, fertilization, irrigation, plant density) to realize sustainable maize production.