Influence of Integrated Nitrogen Management on Release Pattern of Zn, Fe, Mn and Cu under Different Soil Moisture Regimes

A two-year incubation experiment (2015-2016 and 2016-2017) was conducted at College of Agriculture, CAU, Imphal - 04 to ascertain the effect of integrated nitrogen management on release patterns of nutrients overtime at different moisture regimes in soils. The experiment consisted of 12 treatments with three different soil moisture regimes: 40%, 60%, and 80% water-holding capacity. The Incubation study was conducted by discard method and the experiment was conducted in FRBD. Soil samples were collected at 30-day intervals to assess DTPA-extractable micronutrients. Analysis of the data of incubation study revealed that irrespective of different treatments, accumulation of available Fe and Mn gradually increased up-to 60th day of incubation, thereafter continued to decrease slowly up to the last stage of incubation. Comparatively, greater accumulation DTPA-extractable Zn, Cu was also observed at 60 % WHC followed by 40% and 80% WHC at different stages of incubation. Among the treatments, significantly higher concentration of available Zn and Mn was observed in T11 followed by T6. Further, the data pointed out that statistically higher accumulation of DTPA extractable Cu in soil was perceived in T4 followed by T11 throughout the incubation period. The results indicate that Integrated Nitrogen management, particularly with moisture (60% WHC) and organic amendments will improve the soil availability potential of the micronutrients. They should be incorporated with organic & inorganic nutrient sources while managing soil moisture levels under integrated nitrogen management, to find better availability of micronutrients and improve uptakes, performance and long-term fertility of soils.