Effect of Integrated Nutrient Management on Soil Fertility and Soil Microbial Population after Cropping to Wheat Crop in Western Uttar Pradesh

A field experiment was conducted during the rabi season of 2013-14 and 2014-15 at Chandra Shekhar Azad University of Agriculture and Technology, Kanpur to evaluate the different levels of INM on soil fertility of wheat. The experiment was comprising sixteen treatments viz. T1- control, T2- 100% RDF,T3- 100% RDF + S, T4- 100% RDF + S + Zn, T5- 100 % RDF + S + Zn + bio-fertilizer (Azotobactor + PSB), T6- 100% RDF + 25% N through FYM, T7- 100% RDF + 25% N through FYM + S, T8- 100% RDF + 25% N through FYM + S + Zn, T9-100% RDF + 25% N through FYM + S + Zn + bio-fertilizer Azotobactor + PSB, T10-100% RDF + 25 % N through vermicompost, T11- 100% RDF + 25% N through vermicompost + S + Zn + bio-fertilizer Azotobactor + PSB, T12- 75 % RDF, T13-75% RDF + 25% N through FYM, T14- 75% R.D.F. + 25% N through vermicompost, T15-75% RDF + 25 % N through FYM + S + Zn + bio-fertilizer Azotobactor + PSB and T16-75% RDF + 25% N through vermicompost + S + Zn + bio-fertilizer + PSB. Integration of organic manures showed slight increase in EC value while inorganic fertilizers showed slight decrease in EC values in comparison to its initial value which is obviously due to decomposition of organic matter in soil. Maximum increase in organic carbon content was noted with the integration of organic treatments followed by inorganic treatments. It may be due to decomposition and mineralization of organic matter by narrow C: N ratio. Status of N, P, K, S and Zn was slightly increased in all the treatments in comparison to its initial value except control during both the years. Maximum increase in available status of N, P, K, S and Zn was recorded with integration of inorganic, organic and bio-fertilizers with 100% RDF.T11 (100% R.D.F. + 25% N through vermicompost + S + Zn + bio-fertilizer Azotobactor + PSB followed by T9-100% RDF + 25% N through FYM + S + Zn + bio-fertilizer Azotobactor + PSB and minimum at control (T1) during both the years. Maximum microbial population was recorded with T11 (100% R.D.F. + 25% N through vermicompost +S + Zn + bio-fertilizers (Azotobactor +PSB) followed by T9 (100% R.D.F. + 25% N through FYM + S + Zn +bio-fertilizers (Azotobactor + PSB) and minimum at control during both the years.