Effect of Fertilizer Doses and Soil Test Levels on Crop Response of Brinjal (Solanum melongena)

A field experiment was carried out to formulate the fertilizer recommendation for Brinjal crop in Inceptisol of Chhattisgarh. The objectives were to find out the nutritional requirement of the crop. The experimental field was divided in to three fertilizer gradient strips (L₀, L₁ and L₂), which was already created during previous kharif season by adding different graded dose of fertilizer N, P and K with maize as exhaust crop. Thirty-six treatments considered of 3³ factorial combinations of fertilizer N, P and FYM were superimposed over each fertility strip (L₀, L₁ and L₂). Mukta kesi variety of Brinjal was taken as the test crop. The crop response to added nutrients and various regression analyses were performed after the crop harvest. Linear Response Plateau (LRP) and Quadratic Response Plateau (QRP) models were used to relate yield with soil test and fertilizer dose and resulted significantly high R² values suggesting their suitability. Brinjal crop required 0.31 kg N, 0.037 kg P and 0.57 kg K to produce one quintal of Brinjal fruit yield. The LRP model considered constant nutrient use efficiencies for each level of soil test and fertilizer doses. However, QRP model estimated variable soil and fertilizer efficiencies. The special feature of these models was the consideration of yield plateau, which makes them suitable under resource constraints situations.