Field investigations were carried out at the Annamalai University, Experimental Farm, Department of Agronomy, Faculty of Agriculture, Annamalai Nagar, which represents the tail end area of Cauvery Deltaic Zone of Tamil Nadu, India, during January 2007 and 2008 to evaluate the influence of integrated nutrient management technique on microbial population in rice fallow cotton (Gossypium hirsutum L.). The results indicated that considerable increase in microbial population (bacteria, fungi and actinomycetes ) with the combined application of 75% RDF with vermicompost @ 2.5 t ha-1 along with soil application of Azatobactor and Phosphobacteria. This was followed by 100% RDF with vermicompost @ 2.5 t ha-1.
