Influence of chemical fertilizers application on autumn wheat yield in long-term experiences at Agricultural Research and Development Secuieni, Neamţ county, Romania

Abstract

The current paper intends to interpret from a technical point of view the data and yield functions which resulted from applying different fertilizer doses with nitrogen and phosphorus. The analyzed parameters (yield, yield increase, marginal increase) represent basic elements with determining role in establishing the doses and approximating the economic efficiency when applying fertilizers. The data comes from a long time experience with chemical fertilizers at Agricultural Research and Development Station (A.R.D.S.) Secuieni, Neamţ county, Romania, since 1975 and examines the results obtained between 2010-2012. As a result of nitrogen and phosphorus chemical fertilizers application (compared to the unfertilized version N0P0), were achieved yield increases of 5-56%, representing 234-2342 kg/ha. The resulted yield have been influenced by the fertilizer’s type but also by the weather conditions in the research period. The use of phosphorus fertilizers in doses of P40-P160 brought medium yield increases compared to the unfertilized version P0 of 5-13% representing 256-681 kg/ha, and those with N40-N160 nitrogen brought medium increases (compared to the unfertilized version N0) of 15 -35% representing 599-1584 kg/ha. The production increases were directly correlated with the doses used, establishing highly significant correlations. The yield increases achieved by applying 1 kg of fertilizer active matter had medium values of 4.25-8.82 kg wheat/kg active matter P2O5 at phosphorus fertilizers and 9.9-14.97 kg wheat/kg active matter N at nitrogen fertilizers. These increases were indirectly correlated with the applied doses.