Effect of P, S and Bradyrhizobium on yield, nutrient content and uptake by soybean (Glycine max) under rainfed condition

Experiment was conducted in the Kharif season, 2016 under rainfed conditions at experimental farm of Birsa Agricultural University, Kanke, Ranchi, Jharkhand to investigate the Effect of P, S and Bradyrhizobium on yield, nutrient content and uptake by soybean (Glycine max) under rainfed condition. The experiment was laid in a split-split plot design with 18 treatment combinations and three replications comprising two levels of inoculation (I0 and I1), three levels of phosphorus (P40, P60 and P80 kg ha-1) and three levels of sulphur (S0, S15 and S30 kg ha-1). Parameters measured were grain yield, N, P and S nutrient content and its uptake by dry matter of soybean. The results indicate that grain yield (23.91 q ha-1) of soybean was highest with 80 kg P2O5 ha-1 which was significantly superior over 60 kg and 40 kg P2O5 ha-1. Soybean responded to applied sulphur but there was no significant difference between two levels of sulphur for grain yield (23.62 q ha-1 @ 30 kg S ha-1 and 22.31 q ha-1 @ 15 kg S ha-1). Rhizobium inoculation significantly increased the grain yield (23.36 q ha-1) of soybean. Application of different levels of P, S and Rhizobium inoculation did not have significant influence on nitrogen, phosphorus and sulphur content in grain and straw of soybean. Total nitrogen and sulphur uptake by soybean significantly increased from 160.44 to 185.66 kg ha-1 and 13.34 to 15.43 kg ha-1 respectively, with increasing levels of phosphorus from 40 to 80 kg P2O5 ha-1 while, in case of total phosphorus uptake, application of phosphorus @ 80 kg P2O5 ha-1(16.34 kg ha-1) was found to be significant over 40 kg P2O5 ha-1 which was at par with 60 kg P2O5 ha-1 (15.36 kg ha-1). Application of 30 kg S ha-1 retained significantly higher total uptake of nitrogen (183.36 kg ha-1), phosphorus (16.09 kg ha-1) and sulphur (15.43 kg ha-1 ) compared to 0 kg S ha-1 (164.50, 14.12 and 13.53 kg ha-1 for total uptake of N, P and S respectively). Rhizobium inoculated treatment had significantly higher total uptake of nitrogen (180.97 kg ha-1), phosphorus (15.98 kg ha-1) and sulphur (15.10 kg ha-1) as compared to uninoculated (166.12, 14.09 and 13.80 kg ha-1 for total uptake of N, P and S respectively).