Wheat Yield and Post-Harvest Fertility Status of Calcareous Soil Using Shallow and Deep Tillage and Integrated Nutrient Management (INM)

The study was conducted in Research Farm of the University of Agriculture, Peshawar during wheat crop season 2015-16 to test different nutrient inputs for their effect on wheat yield and soil fertility status under different tillage practices. Randomized Complete Block Split Plot Design with three replications was used for the study where nutrient inputs were allotted to sub-plots whilst tillage practices were studied in main plots. Nutrient input consisted of Farmer’s fertilizer practice (FP; N:P2O5:K2O=60:45:00 kg ha^-1), Recommended dose (RD; N:P2O5:K2O=120:90:60 kg ha^-1), Farmyard manure (FYM) alone at the rate of 5, 10, 15 and 20 t ha^-1 and the integration of 5, 10 and 15 t ha^-1 FYM with 75, 50 and 25% of the RD, respectively. Tillage practice included shallow tillage (ST; 0-20 cm) and deep tillage (DT; 0-40 cm). The FYM alone resulted in increased soil NPK, organic matter (OM) and the electrical conductivity (EC) but failed to improve the yield significantly. However, the RD, along with improving these parameters, also increased the yield significantly over the FP. Amongst all treatments, the 5 t ha^-1 FYM and 75% NPK of the RD (INM5:75) stood superior with respect to yield as well as soil fertility status. However, efficacy was negative under deep tillage compared to shallow tillage for all treatments since yield as well as harvest Index (HI), mineral nutrients and OM content in soil were significantly lower and pH and EC higher under deep tillage. Results suggested that, unless otherwise necessary, deep tillage in alkaline calcareous soil should be avoided, preventing lime resurfacing from depth and keeping the applied amendments concentrated in surface layer.