János Nagy Debreceni Egyetem Agrár- és Gazdálkodástudományok Centruma, Mezgazdaság-, Élelmiszertudományi és Környezetgazdálkodási Kar, Földhasznosítási, Műszaki és Területfejlesztési Intézet, Debrecen
Adrienn Ványiné Széles Debreceni Egyetem Agrár- és Gazdálkodástudományok Centruma, Mezgazdaság-, Élelmiszertudományi és Környezetgazdálkodási Kar, Földhasznosítási, Műszaki és Területfejlesztési Intézet, Debrecen
The effect of crop production factors on maize yield are examined on chernozem soil in a more than 30 year old long-term experiment on the Látókép Experiment Site of the Centre for Agricultural and Applied Economic Sciences of the University of Debrecen. The aim of research is to evaluate the effect of fertilisation, cultivation, plant number, genorype and irrigation. The analysis of the data in the database of the examined period makes it possible to evaluate the effect of maize yield, as well as that of the crop production factors and the crop year, while the correlations and interactions between these factors were also examined. During the examination of the cultivation treatments, it was concluded that the highest yield was obtained as a result of autumn ploughing, but its effect largely differs in the irrigated and the nonirrigated treatments. Based on our examinations, strip cultivation should be applied periodically (e.g. strip – strip – ploughing – loosening) in areas with favourable soil conditions free from compacted layers. In years with smaller, average precipitation supply or when the precipitation was higher than average, higher plant numbers were more favourable. Under drier conditions, but especially in several consecutively dry years, a lower plant number can be recommended which is not higher than 60 thousand per hectare. In the case of favourable water supply, 70-80 thousand plants per hectare can be used. The yield increasing effect of fertilisation was significant in the case of both non-irrigated and irrigated conditions, but it was much more moderate in the non-irrigated treatment. The extent of weed coverage was significantly affected by the previous crop. In the case of a favourable previous crop (wheat), the weed coverage was significantly lower than after an unfavourable previous crop (maize). In the case of the same previous crop (maize), the extent of weed coverage was mostly determined by the crop year and the extent of precipitation supply. Irrigation is not enough in itself, because if it was not accompanied by intensive nutrient management, yields started to decline. The results of researhc, development and innovation contributed to the technological method which makes it possible to apply locally adjusted sowing seed, fertiliser and pesticide in a differentiated way, as well as to change the method of operations within the given plot.