Influences of Liming on Vertisol Properties and Yields of The Field Crops

The field experiment with fertilizer “Njival Ca” (waste of the Serbian glas factory in Paracin: calcite 98.5% CaCO3 granulation >0.1 mm) was conducted in spring 1998 on the Kragujevac vertisol with the treatments as follows (t ha-1 on CaCO3 basis): 0 (the control), 0.8 and 1.6 (every year), 4.0 and 8.0 (at start of the experiment). The trial was conducted in fíve replicates and in triplicate for wheat-maize-soybean roration. In general, liming considerably influenced on yields of the field crops and single application of the high rates are better choice in comparison with repeated use of the low rates. For example, by yield increases in comparison with the control were as follows (comparison single application of 8 t ha" and repeated applications of 1.6 t ha−1): 29% and 9% (maize), 7% and 3% (wheat), 24% and 9% (soybean), respectively.