Surface application of flue dust, aqueous lime, sewage sludge and limestone on soybean crop

The objective of this work was to evaluate the effect of the surface application of sewage sludge, aqueous lime, flue dust and limestone on soybean nutrition and yield in no-till system. The experiment was arranged in a randomized complete block design, in factorial scheme of 4x4+1, and consisted of four residues: centrifuged sewage sludge (CSS), biodigestor sewage sludge (BSS), flue dust (FD) and aqueous lime (AL), at 0, 2, 4 and 8 Mg ha(-1), and one additional control treatment with dolomitic limestone at 2 Mg ha(-1). The soybean plants showed greater contents of nitrogen, phosphorus and calcium in 2003, 2004 and 2005, and potassium contents in 2003 and 2004, due to the treatments CSS, BSS, FD, AL and limestone. Soybean grain yield was also enhanced due to surface applications of the treatments in no-till system in 2003, 2004 and 2005. The phosphorus and calcium contributed to increase soybean yield in 2003 and 2004.