Influence of inm practices on post harvest soil nutrient status and biological properties in rice

Field experiments were conducted for evaluating different organic manures on post harvest soil biology in rice during 2007 and 2008. Both the years rice was cultivated during samba season (August to January). The soil of the experimental farm is deep clay, low in available N (198 kg ha-1), medium in available P (20.9 kg ha-1) and high in available K (271.0 kg ha-1). The experiment was conducted in randomized block design and replicated thrice. It comprised of eight treatments which includes absolute control, recommend dose of nitrogen alone and in combination with different organic manures namely green manure pressmud and vermicompost. Rice cultivar CO 43 was used as test cultivar. Significant increase in microbial population of fungai, bacteria and actinomycetes were recorded in 100% RDN along with vermicompost @ 5t ha-1 over other treatments and control. Also the same treatment recorded significantly higher soil available N and K and higher organic carbon after the harvest of the crop. But higher soil available P was registered under 100% RDN along with pressmud compost @ 10 t ha-1. The least values were recorded in absolute control (no organic and chemical fertilizers).