Long - Term Effect of Organic Materials and Fertilizers on Soil Properties in Pearl Millet-Wheat Cropping System

An investigation was undertaken to study the effect of long- term application of inorganic fertilizers and organic materials (farmyard manure, wheat straw and green manure) on soil physico-chemical properties, soil organic carbon, nutrient availability and crop yield after 22 cycles of pearl millet and wheat at Research Farm of CCS HAU, Hisar. The experiment consisted of five treatments including control, inorganic fertilizers alone, and fertilizers along with organic materials to substitute 50% N through farmyard manure (FYM), wheat straw and green manure (Sesbania aculeata). Continuous use of FYM, wheat straw and green manure in conjunction with fertilizers increased the soil organic carbon (OC), hydraulic conductivity, available N, P K status and wheat yield, and decreased soil bulk density, soluble salts and pH. Among organic materials, FYM resulted in highest OC (0.54%), available N (242.8 kg/ha), available P (17.7 kg/ha) and available K (318.5 kg/ha) level in soil. In general, the application of organic materials reduced the soil bulk density by 3.3% as compared to the fertilizers alone. Among different treatments, the grain and straw yield of wheat was highest where FYM (50% of N) was applied with fertilizers than the application of wheat straw, green manure or inorganic fertilizers alone. The results suggest that integrated use of inorganic fertilizer in combination with organic materials facilitates soil physical and chemical environment congenial for achieving higher crop productivity under pearl millet-wheat cropping system.