Dynamics of Nitrogen on Soybean Field Amended with Poultry Manure

A field experiment was carried out at the Federal University of Agriculture, College of Plant Science and Crop Production farm Abeokuta, Ogun State, Nigeria, to determine the effect of nitrogen releases from poultry manure, phosphorus source and bradyrhizobium inoculation on soybean (Glycine max L.) growth and yield. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three treatments consisting of poultry manure (0, 5, 10, tons/ha), phosphorus source (single super phosphate, mycorrhiza) and bradyrhizobium replicated three times. The poultry manure was applied two weeks before planting, phosphorus source and bradyrhizobium were applied at planting. Agronomic parameters in soybean were assessed at 4 to 14 weeks after planting (WAP) forthrightly: leaf area, stem girth and plant height all showed the same trend from the analyses i.e. not significant; effect of interaction of poultry manure, phosphorus source and bradyrhizobium inoculation on soil nitrogen (ammonium and nitrate), at 4 weeks after planting, single super phosphate and 5 tons of poultry manure had the highest effect on ammonium nitrogen. While at 8 weeks after planting, mycorrhiza and 0 ton of poultry manure had the highest effect on nitrate nitrogen and at 8 weeks after planting, single super phosphate and 0 ton of poultry manure had the highest effect on nitrate nitrogen. Mycorrhizal gives higher plant, girth and yield of soybean production, and increased soil nitrogen.