Soil Test based Fertilizer Recommendations under Integrated Plant Nutrition System for Rice-Rice-Pulse Cropping Sequence

Field experiments were conducted on Typic Ustropept of Lower Bhavani Project area of Tamil Nadu to assess the fertilizer requirements under integrated plant nutrition system (IPNS) for rice-rice-residual pulse cropping sequence. Following Ramamoorthy's inductive methodology-cum-targetted yield model, fertilizer adjustment equations were formulated for rice both in kharif and rabi seasons. From these equations, the efficient and economic rates of fertilizers were calculated. The quantity of fertilizers that could be adjusted to the levels and sources of organic manures was evaluated to be 38 kg N, 13 kg P₂O₅ and 33 kg K₂ O ha⁻¹ for fertilizers with GM (Sesbania rostrata); 10–12 kg P₂O₅ ha⁻¹ for fertilizers with PB (Bacillus megaterium var. phosphaticum);40 kg N, 26 kg P₂O₅ and 33 kg K₂ ha_-1 for fertilizers with GM plus PB.