Influence of Tillage, Residue, and Nutrient Management Practices on Physico-chemical and Biological Properties of Soil under Salt-affected Conditions in Wheat (Triticum aestivum L.) Crop

Abstract

Sustainable soil management practices such as conservation tillage, residue retention, and integrated nutrient management are important for improving soil health and crop productivity under salt-affected conditions. The field experiment was conducted during the rabi season of 2022-23 at the Research Farm, School of Agriculture, Galgotias University, Greater Noida, Gautam Buddh Nagar, Uttar Pradesh, India. The experiment was laid out in a split-plot design with three replications. The main plot treatments consisted of two tillage systems, viz., zero tillage and conventional tillage. The sub-plot treatments comprised five residue and nutrient management practices: 100% rice residue (RN₁), no residue + 100% recommended dose of fertilizers (RDF) (RN₂), 100% rice residue + 75% RDF (RN₃), 100% rice residue + 100% RDF (RN₄), and 100% rice residue + 125% RDF (RN₅). The results revealed that tillage and residue–nutrient management practices had a non-significant effect on soil pH, organic carbon, and electrical conductivity. However, relatively higher values of organic carbon were observed under zero tillage and RN₅ (100% rice residue + 125% RDF), followed by RN₁ (100% rice residue). In contrast, available nitrogen (N), phosphorus (P), and potassium (K) were significantly influenced by the treatments, with values increasing over the initial soil status. Zero tillage in combination with residue and nutrient management practices significantly enhanced the availability of N, P, and K in the soil after crop harvest. The highest available N, P, and K were recorded under RN₅ (100% rice residue + 125% RDF). Furthermore, soil biological properties were markedly influenced by the treatments. The maximum microbial population of bacteria (39.06 × 10⁶ CFU g⁻¹), fungi (14.13 × 10³ CFU g⁻¹), and actinomycetes (21.63 × 10⁴ CFU g⁻¹) was recorded under zero tillage. Among residue and nutrient management practices, the highest microbial population of bacteria (39.79 × 10⁶ CFU g⁻¹), fungi (14.88 × 10³ CFU g⁻¹), and actinomycetes (22.12 × 10⁴ CFU g⁻¹) was observed with RN₅ (100% rice residue + 125% RDF).