Effect of Long-term Use of Mineral Fertilizers, Lime and Farmyard Manure on the Crop Yield, Available Plant Nutrient and Heavy Metal Status in an Acidic Loam Soil

Abstract

The effect of balanced and imbalanced nutrient use on crop yield and availability of plant nutrients over the years is being studied in a Paleustalf of Ranchi under long-term permanent manurial trial. The present paper reports the long-term effect of organic manures, fertilizers and lime on secondary and micronutrient status of an acid soil. Results revealed that the yield of maize under the treatments decreased in the order: NPK+lime > FYM+PK > NPK > NP > control > N. Lime application with NPK resulted in significantly higher uptake of P, Ca, Mg, S and B. Imbalanced use of N alone had a depressing effect on soil pH and Ca uptake by maize. The pH of acid soil (5.5) increased by 0.9 units with lime and fertilizer use, while it decreased in unlimed plots. Farmyard manure treated plots had a favourable influence on soil pH and organic carbon content. Application of N, NP and NPK fertilizers did not increase exchangeable Ca status of acid soil. The DTPA-extractable micronutrients in acid soils increased in N, NP and NPK treated plots while a decrease was recorded in limed plots. Liming decreased the DTPA-Cd in soil while FYM increased its content.