Effect of sources and levels of organic manures on periodical release rate of nitrate nitrogen and soil properties of entisol

Abstract

An incubation study was conducted during 2024-2025 with three sources of organic manures viz., FYM, vermicompost and pressmud compost and three levels of organic manures, i.e., 2, 4 and 6 t ha-1, along with a separate control treatment. The soil samples were analysed periodically at 15 days intervals for the release of nitrate nitrogen up to 90 days of incubation (DAI). Vermicompost application at 6 t ha-1 recorded the highest NO3--N over all the incubation period and it was followed by PMC 6 t ha-1. The periodical release of NO3--N was maximum during 30-45 days of incubation and gradually declined thereafter in all the treatments. The highest release of NO3--N was exhibited by vermicompost application at 6 t ha-1 (24.86 mg kg-1) and it was followed by PMC at the rate of 6 t ha-1 (22.55 mg kg-1) at 30-45 days of incubation. Among sources, the Significantly higher soil organic carbon (0.48%), available nitrogen (193.15 kg ha-1) and phosphorus (25.65 kg ha-1) were recorded with application of FYM, vermicompost and PMC, respectively. Whereas application of vermicompost level @ 6 t ha-1 recorded significantly the highest available nitrogen (215.66 kg ha-1), while the highest available phosphorus (28.46 kg ha-1) was reported with application of PMC @ 6 t ha-1.