Studies on site specific nutrient management (SSNM) on growth and yield of groundnut (Arachis hypogaea) under irrigation in southern Karnataka

A field experiment was conducted at the Main Research Station, University of Agricultural Sciences, Hebbal, Bangalore, to know the effect of site specific nutrient management (SSNM) on growth and yield of groundnut. The fertilizers were applied to the crop based on uptake pattern, target yield and soil fertility status. The study indicated that application of fertilizers based on SSNM for target yield of 2.5 t ha⁻¹ + S (10 kg ha⁻¹) + B (10 kg ha⁻¹) + Zn (12.50 kg ha⁻¹) recorded significantly higher growth parameters viz., plant height (45.3 cm), number of branches (8.10), leaf area (814.95 cm⁻²), leaf area index (2.72) and total dry matter accumulation (31.82 g plant⁻¹). The yield parameters viz., total number of pods per plant (19.57), pod weight per plant (12.05 g), 100 kernel weight (34.74 g) and shelling per cent (75.32) were significantly higher with the application of fertilizers based on SSNM for targetyieldof 2.5tha⁻¹+ S + B + Zn compared to recommended dose of fertilizer. The Maximum gross returns were obtained in T₄ (application of SSNM for target yield of 2.5 t ha⁻¹ + S + B + Zn)(Rs.79219), whereas, higher net returnsand B: C ratio were obtained with T₃ (SSNM fortarget yield of 2.5 t ha⁻¹) (Rs. 46771 and 2.47 respectively) and lower net returns and B: C ratio were with application of Rec. NPK + FYM (T₁) (Rs. 33852 and 2.13 respectively).