Impacts of maize based conservation agriculture production system on soil properties in North Central Plateau Zone of Odisha

Natural resources and environmental quality in agriculture are subjected to degradation, warrant for immediate and long term solutions. Conservation agriculture systems with suitable crop and soil management packages have been identified as one of the solution. The North central plateau zone of Odisha has an undulating topography and the soils of these areas are facing various types of losses. Maize is a major crop in this agroclimatic zone. To study the impact of maize based cropping system under conventional and minimum tillage practice a field experiment was conducted at Regional Research and Technology Transfer Station (RRTTS), O.U. A.T, Kendujhar during Kharif and subsequent Rabi season (2011-2012). Conventional and minimum tillage with maize and maize+cowpea intercrop were taken during kharif and each treatment plot was divided into 3 subplot treatments like horsegram, mustard and fallow during Rabi. Soil sample were collected before Kharif and after Kharif and Rabi season to study the impact of treatments on soil bulk density, texture, pH, organic carbon, available N, P, K, Ca, Mg following the standard procedure. Nutrient dynamics was studied by resin bag technique. Yield and nutrient uptake by crop were also recorded. From the above study it was revealed that minimum tillage improved the bulk density of soil by reducing its value 0.007 Mgm than conventional tillage during Kharif. Decrease in sand with increase in silt and clay content was observed in minimum tillage than conventional tillage. The pH and organic carbon of the soil had increased to a tune of 0.2 unit and 0.29g/Kg in minimum tillage than conventional tillage. The available nutrient content of soil were found increased by 4.5Kg/ha N, 0.06Kg/ha P, 4.8Kg/ha K, 0.46 cmol(p)/Kg Ca and 0.32 cmol(p)/Kg Mg after harvest of Kharif crops in minimum tillage than conventional tillage. Nutrient dynamics studied by resin bag technique revealed 17.93 ppm N/5g resin, 22.6 ppm P/5g resin, 56.92 ppm K/5g resin, 30.69 ppm Ca/5g resin, 12.04 ppm Mg/5g resin were estimated in conventional tillage over a value of 15.35 ppm N/5g resin, 20.56 ppm P/5g resin, 54.01 ppm K/5g resin, 29.14 ppm Ca/5g resin,11.59 ppm Mg/5g resin in minimum tillage treatments. From the analysis of nutrient uptake by different crops it was found that the maximum uptake of nutrients to a tune of 158.0 Kg/ha N, 17.17 Kg/ha P in conventional tillage maize+cowpea intercrop in Kharif followed by horse gram in Rabi and minimum in MT-M-F. But the potassium uptake was maximum 122.8 Kg/ha in CT-M+C-M and minimum in MT-M-F. Maize equivalent yield was found to be maximum 85.83 qha in conventional tillage maize+cowpea intercropping treatment followed by minimum tillage maize+cowpea, conventional tillage maize and minimum tillage maize in decreasing order. The more yield was observed in case of conventional tillage than minimum tillage due to better root proliferation at initial period of conservation practice. During Rabi season the bulk density, fine earth fraction, pH, organic carbon, available N,P, K, Ca, Mg of soil followed the similar trend as Kharif season in different tillage treatments. Among different crops horse gram reduce the bulk density by 0.001Mgm ,increase the pH 0.01 unit, organic carbon content 0.03g/Kg , available N 0.5Kg/ha, available P 0.02 Kg/ha, available K 0.2 Kg/ha, available Ca 0.02 cmol(p)/Kg, available Mg 0.03 cmol(p)/Kg than mustard crop. So horse gram was found to superior than mustard. Minimum tillage although gave less yield than conventional tillage in the first year but improve the soil physical properties and chemical properties slowly.