Effect of Organic Matter Recycling in Long‐Term Fertilization Trials and Model Pot Experiments

Abstract

Sustainable agriculture implies the use of biological resources. Farmyard manuring (FYM) and ploughing in plant residues have an important role in maintaining soil fertility. Our aim was to study the effect of various combinations of organic and mineral N‐fertilizers on the Corg content of the soil, grain yield, dry matter production, and N uptake of barley. A model pot experiment was set up with spring barley. Large pots were filled with 46 kg sandy loam soil originating from the plots of the “International Long‐term Experiments for Investigating the Effect of Organic and Inorganic Fertilisers,” Keszthely, Hungary. The field experiment, which was set up in 1983, contains three crop rotations with winter wheat, winter barley, and maize. Treatments: 1) inorganic fertilizers only with increasing N doses (N); 2) FYM in every 3rd yr+N; 3) stalk, straw, or green manure+N. Yield results gained in the field experiment with winter barley were also evaluated. In the 18th yr of the experiment, FYM+N resulted in significantly higher Corg content than with treatments 1 and 3. Grain yields in the field trial were the lowest in treatments without organic matter recycling. In the pot experiment, dry matter production and N uptake of the grains and vegetative plant parts were significantly higher in treatments with FYM+N. Our results clearly prove the advantage of FYM combined with mineral fertilization over the other treatments.