The experiment was conducted under field conditions at Instructional cum Research Farm, College of Agriculture, Raipur (Chhattisgarh) during kharif season 2011-12. The data observed that treatment T2 (1.47%, and 65.42 kg ha(-1)) was recorded significantly higher N content % and N uptake ha(-1) in the straw, followed by T9 (1.40% and 58.34 kg ha(-1)) and T7 (1.40% and 55.86 kg ha(-1)).Whereas, N content % and N uptake in grain recorded significantly similar results in the treatment T9 (6.31% and 157.12 kg ha(-1)) and T7 (6.29% and 153.04 kg ha(-1)). However, total N uptake by soybean was recorded significantly highest under treatment T2 (235.18 kg ha(-1)) followed by T9 (215.46 kg ha(-1)). Number of nodulation plant(-1) was recorded significantly higher in treatment T6 (80.00) which was at par with T2 (79.33), T9 (77.67) and T7 (71.67). Dry weight of nodule, N content of nodule, number of pods plant-1, grain yield and straw yield was recorded significantly higher in treatment T2 (0.196 g plant(-1),7.12%,34.12, 26.65 qha(-1) and 44.51 qha(-1)) which was at par with T9 (0.187 g plant(-1),6.89%,32.14, 24.90 qha(-1) and 41.09 qha(-1)), T7 (0.181 g plant(-1),6.820/0,31.47 qha(-1) and 24.33 qha(-1)), T6 (0.178 g plant(-1),6.75%,29.60 and 23.92 qha(-1)) and T3 (0.170 g plant(-1),6.73%,28.50 and 23.65 qha(-1)). Response of amended melamine phosphate on Rhizobial population, gram(-1) of soil at 45 DAS T2 (11.03 gm(-1) soil) was recorded significantly higher among all the treatments which was at par with treatment T9 (10.6 gm(-1) soil) and T7 (9.99 gm(-1) soil). Soil respiration and soil dehydrogenase activity was found significantly higher in treatment T9 (0.375CO2/hr/100g soil, 22.0p mu g/TPF/h/g soil) which was at par with T2 (0.367 CO2/hr/100g soil) and T7 (0.356CO2/hr/100g soil) incase of soil respiration and T2 (20.6p mu g/TPF/h/g soil) was at par in soil dehydrogenase activity.