Influence of Manuring of Microbial Activity and Organic Matter Decomposition in Rice Soil

A field experiment was conducted in the central farm of OUAT during 2005-2008 with rice-rice cropping sequence using inorganic, organic and integration of both type of fertilizers. The soil samples after completion of Rabi rice crop was taken for present study purpose. Due to application of readily available sources of energy along with organic nutrients the microbial population in soil was increased which influenced the microbial decomposition process. The rate of organic matter decomposition was studied by incubation method, from the result it was observed that during fifth week of incubation with dextrose the highest value of 21.98 mg carbon/100g soil was obtained in silicate slag (Soil conditioner) treated plot, where as lowest value was observed with unammended soil of control plot. On the other hand the highest population counts of 13.7×10⁷ number of bacteria and 3.14×10⁶ number of fungi were observed in FYM treated plot where as the highest of 2.6×10⁵ number of actinomycetes were observed in silicate slag treatment.