Impact of different ratios and levels of nitrogen and phosphorus on growth, yield and nutrient uptake of rainfed soybean

Abstract

A field experiment was carried out during kharif 2015 with thirteen ratios of nitrogen (N) and phosphorus (P2O5) fertilizers with constant potassium level (25 kg K2O ha-1) on soybean cultivar DSb 21. The treatment receiving N/P fertilizer ratio of 0.70 (basal application of 18 kg N, 46 kg P2O5, 25 kg K2O ha-1 + foliar application of nitrogen @ 7 kg N ha-1 at initiation of flowering and foliar application of nitrogen @ 7 kg N ha-1 at 15 days after first foliar spray) recorded significantly higher seed yield (3217 kg ha-1), haulm yield (3788 kg ha-1), number of filled pods plant-1 (44.73), total number of pods plant-1 (47.57) and 100 seed weight (15.40 g) This treatment also recorded significantly higher total dry matter production (34.15 g) that higher gross monetary returns, net monetary returns and B : C ratio (Rs. 1,12,595, Rs. 89,770 ha-1 and 4.93, respectively).