The impact of environmental factors on the protein content and yield of maize grain at different nutrient supply levels

Abstract

Climate change poses a new challenge for maize producers which calls for the re-thinking of each production technological element. Professional nutrient replenishment may represent an alternative for the mitigation of yield decrease caused by climate change by means of improving yield stability from the aspect of global food safety, as well as increasing yield and improving yield quality. In the course of a six-year (2011-2016) research, under changing climatic conditions we studied how different fertilization methods - 11 different N doses (0-300 kg ha-1) - affect the productivity of maize and protein content of grains.The experiment was carried out in Hungary (47° 33' N, 21° 26' E, asl: 111 m) in the long-term experiment of the University of Debrecen.The results of the examined years classified on the basis of precipitation, effective heat units (HU) and potential evapotranspiration (PET) showed a significant yield limitation effect of precipitation shortage. In drought, maize yield decreased by 16% (P < 0.001) in comparison with the average crop year. The wet crop year resulted in a 19% yield increase (P < 0.001). Protein content was lower (-11.7%) in the dry and warm crop year than in the wet crop year. The maize grain content is in a close positive correlation with yield at a high level of confidence in all examined years (P < 0.001). The closest correlation was observed in the dry crop years (2012 r=0.703; 2013 0.728; 2015 0.747). As a summary of the performed research, precipitation improved the availability of nutrients. The economical yield level can be achieved with lower NPK ha-1 nutrient doses of 120:92:108 kg in wet crop years. In dry crop years, the harmful effect of climate change can be mitigated and yield safety can be improved with higher nutrient replenishment. Higher protein content results from the treatment combinations with higher N and P needs and proper nutrient proportions.