Dependence of corn yield on weather conditions and nitrogen fertilization in IOSDV Novi Sad

Abstract

A stationary field trial with organic and mineral nitrogen fertilizers (IOSDV) was established at Rimski Šančevi experiment field near Novi Sad in 1983/84. The trial included the following organic fertilizers: A1-only mineral fertilizers; A2-manure (40 tha−1), applied once in the course of rotation, under sugar beets; A3-harvest residues of all crops in the rotation; A4-harvest residues + liquid manure, applied twice in the course of rotation (30 m3 each), under sugar beets and corn. Each variant of organic fertilization included five nitrogen doses, from 0 to 200 kg ha−1, with 50 kg ha−1 intervals between the doses. The trial was established by the split-plot method, in three replications and a four-crop rotation: sugar beet – spring barley – corn – wheat. This paper analyzes only the data for corn from the fourth and fifth rotations (from 1996 to 2003). The following results were obtained. Weather conditions during growing season, especially the amounts and distribution of rainfall, affected significantly the yield of corn grain. They also affected the experimental variants, i.e. organic and mineral fertilization. In years with favorable conditions, the effects of organic and mineral fertilizers were positive. Yield level depended more on mineral nitrogen fertilizers than on organic ones. In dry years with high rainfall deficit, organic fertilizers had a higher effect on yield level, i.e. they were more effective in mitigating the adverse effects of drought than the mineral nitrogen fertilizers. There existed significant relationships between the years and the studied fertilizer combinations. Organic fertilizers had the highest effects in the control variants. These effects went down as the nitrogen dose increased. Effect of nitrogen dose on corn yield depended only partially on the type of organic fertilizer. There existed significant relationships between the applied nitrogen doses and corn yield. In the variants that included manure and liquid manure, less mineral nitrogen provided maximum corn yield. The situation was opposite in the other two variants.