Conjoint Application of Lime, Organics, Inorganic Fertilizers, and Bio-fertilizers Increases Groundnut Productivity, Available Phosphorus and Microbial Biomass Phosphorus in Acidic Soil of Tripura, India

In Tripura, India the soil productivity is less due to its light texture, acidic in nature, low fertility status, low microbial activity. Thus, a field experiment on groundnut (Arachis hypogaea L.) was carried out on acidic soil of Khowai district of Tripura during 2017 and 2018 to evaluate the impact of the application of various combinations of lime, farm yard manure (FYM), poultry manure (PM), and rhizobium with the recommended doses of NPK on groundnut productivity, available phosphorus (P) and microbial biomass phosphorus (MBP) content of acidic experimental soil. The experiment was conducted using a randomized block design (RBD) with 13 treatments with various combinations of application of lime, farm yard manure (FYM), poultry manure (PM), and rhizobium with the recommended doses (RD) of NPK, each having 3 replications. Both initial and post-harvest soil samples were collected and analyzed to estimate the available P and MBP content. Results indicated that the use of the different combinations of the RD of NPK accompanied by the application of lime, organic manure (FYM or PM) and seed treatment with Rhizobium significantly increased available P and MBP content in the post-harvest soil which has resulted in increased seed yield of groundnut compared to the RD of NPK alone. Again, the use of RD of NPK @ 20:60:40 kg ha-1 conjointly with lime (@ 1/5th LR), PM (@ 5 t ha-1), and treating the seeds with Rhizobium @ 20 g kg-1 of seed might be recommended to the growers in achieving higher groundnut productivity with better return in acid soil of Tripura, India, as it showed maximum enhancement in groundnut productivity as well as available P2O5 content in post-harvest soil.