Nine Years of Integrated Nutrient Management Practices on Soil Microbial Activities in a Cereal-based Cropping System

Abstract

The present work is a follow-up study to identify the effects of nine years long-term integrated nutrient management practices on soil microbial activities in a cereal-based cropping system which was initiated in 2010. The microbial activities like microbial population and enzyme activities were estimated at three different soil depths; 0-15 cm, 15-30 cm and 30-45 cm, in response to different treatment regimes of inorganic fertilizers, organic manures, biofertilizers, and lime. The results identified a decreasing trend in the microbial population and enzyme activity with increased soil depth. Of all the treatment regimes, the maximum enhancements of dehydrogenase and urease activities were observed when there was a combined application of lime with inorganics and organic manure. Additionally, this treatment also increased the bacterial population while decreasing the fungal and actinomycetes population in the soil. The increased soil microbial activities in this treatment can be attributed to the role of organic manures.