Nitrogen translocation efficiency in wheat depends on N sources and tillage practices

Integrated nutrient management (INM) under reduced tillage practices improve soil properties and plant nitrogen (N) dynamics. The effects of urea, farmyard manure (FYM) and soybean residue (SR) under different tillage systems were evaluated in 2-year field experiments for N translocation and translocation efficiencies. Tillage systems included minimum (MT), conventional (CT) and deep (DT) tillages. The INM treatments were urea (60 and 120 kg FN ha), FYM (10 and 20 tons ha as sole or enriched with 1⁄2 FN), SR (10 t ha as alone or along with 1⁄2 FN) and control. Deeply ploughed plots had higher apparent N translocation (11.3 g kg DM) and apparent N translocation efficiency (69%) compared to less disturbed plots. Control plots had higher apparent N translocation efficiency (75%) than fertilised plots. Among the fertilised plots, the order for increased efficiencies were urea > FYM > SR. Increasing the N content of the soil via fertilisation decreased the N translocation and its efficiencies. It was concluded from the experiment that easily mineralisable source of N and DT had higher had higher translocation and its efficiencies over the more recalcitrant sources and CT system. Understanding the mechanistic approach of such studies under INM is recommended for improving the nitrogen indices and productivity on sustainable basis.