Residual Effect of Humic Acid, PSB and Phosphorus Nutrition on Soil Chemical Properties after Harvest of Rice Crop under the Subtropical Condition of Jammu

Abstract

Field experiments were conducted during Kharif season of 2022 at the Research Farm, WMRC, SKUAST- J, Chatha. The soil of the experimental site was sand clay loam in texture, slightly alkaline in reaction, low in organic carbon and available nitrogen but medium in phosphorus and potassium. The experiment was laid out in Factorial RBD with three factors replicated thrice. Twenty treatment combinations comprising of five Humic acid treatments (Control, Soil Application of Humic acid @ 2.5kg/ha & 5kg/ha (Market ready), and Soil Application of Humic acid @ 2.5kg/ha & 5kg/ha (FYM), two PSB treatments (With and without PSB) and two levels of Phosphorus nutrition (100% Recommended N:100% Recommended P - 15:40 kg/ha and 100% Recommended N:75% Recommended P - 15:30 kg/ha). The utilization of Humic acid at a rate of 5 kg/ha, sourced from both Market Ready and Farm Yard Manure (FYM), combined with seed treatment employing (PSB) and a nutrient application of 100% recommended nitrogen (N): 100% recommended phosphorus (P) - 15:40 kg/ha, exhibited a more pronounced and favorable residual impact on soil properties. This was evidenced by notable improvements in organic carbon, available nitrogen, phosphorus, and potassium levels, surpassing their initial values but shows in non-significant results. Furthermore, this treatment employing humic acid application, PSB & Phosphorous nutrition showed improvement in seed yield and straw yield but failed to show significant results in residual rice crop.