The objective of the demonstration trial conducted in a dark red latosol with 2.9 cmol(+)/dm³ of Ca and 1.0 cmol(+)/dm³ of Mg, was to observe possible Ca effect on soybean yield. The treatments were: absolute check, MAP (100 kg/ha), shell lime (200 kg/ha), shell lime (200 kg/ha) + MAP (100 kg/ha), Arad rock phosphate (200 kg/ha) and Arad rock phosphate (200 kg/ha) + ammonium sulfate (50 kg/ha).
Results: treatments with MAP and ammonium sulfate presented better sprouting and initial development; there was no difference of foliar Ca among the treatments; there was no difference among the treatments in the nodulation and in soybean yield.