Organic and Inorganic Nutrient Management in Combination with Rice Residue Retention Influence the Productivity and Soil Health of Zero Tillage Wheat (Triticum Aestivum L.)

Purpose: The primary goal of this study was to understand how nutrient management and residue retention affect productivity, nutrient uptake, soil physicochemical properties and partial nutrient balance in zero-tillage wheat (Triticum aestivum L.). Methods: A field trial was conducted in the eastern Gangetic Plains of India in a split-plot design, replicated thrice, evaluated 20 treatment combinations consisting of varying unchopped rice residue loads (0, 15, 30 and 45 cm retention from ground level) in main plots and different nutrient management options, viz., recommended rates and nutrient expert (NE)-based rates with and without the seed-inoculated biofertiliser Azotobacter and phosphate-solubilising bacteria (PSB), along with a no fertilizer application control in subplots. Wheat variety of the study was DBW 187. Results: Results revealed that retaining 30 cm of unchopped rice residue above ground level with nutrient management through NE + biofertiliser (Azotobacter + PSB) significantly increased grain yield and nutrient uptake. With increasing residue load, the bulk density and soil pH decreased slightly with increasing organic carbon, leading to better soil health. The residues retained at 45 cm above ground and NE based nutrients strategies, substantially enhanced the availability of soil NPK. The partial nutrient balance highlighted negative for nitrogen and phosphorus but positive for potassium in all the treatments; however, the depletion decreased significantly, with balanced fertilization and increased residue retention. Conclusion: The results highlight the superior yield performance of zero-tillage wheat with the retention of preceding unchopped rice residue at 30 cm and balanced nutrient management. It also facilitates a marked improvement in sustainable soil health and partial nutrient balance.