Soil Test Crop Response Correlation Studies Under Integrated Plant Nutrition System for Hybrid Maize on an Alfisol.

Soil Test Crop Response correlation studies were carried out in maize under Integrated Plant Nutrition System (STCR-IPNS) on Typic Rhodustalf of Tamil Nadu, adopting "Inductive cum Targeted yield model". The basic parameters for the "Targeted yield model" viz. nutrient requirement (NR), contribution of nutrients from soil (Cs), fertilizer (Cf) and farmyard manure (Cfym) were computed from field experimental data. Using these parameters, the fertiliser prescription equations were developed under IPNS and ready reckoner of fertiliser doses were formulated for desired yield target of maize for a range of soil test values. The quantity of fertilizer nutrients that could be saved due to the application of FYM @ 12.5 t ha-1 was assessed to the tune of 40, 20 and 26 kg fertilizer N, P2O5 and K2O respectively, when applied along with the NPK fertilizers. The per cent reduction in fertilizer N, P2O5 and K2O under IPNS increased with increasing soil available NPK. [ABSTRACT FROM AUTHOR]