Effect of combined use of tillage and nutrient management practices on soil quality indicators and indices under maize (Zea mays) based cropping system in rainfed inceptisols

Abstract

An experiment was conducted in the rainfed Inceptisols of Rakhdhiansar in Kandi areas of Western Himalayas of South Kashmir and Kumaon, India for four years to assess the influence of combined use of tillage and nutrient management treatments on soil quality under maize based cropping system. The experiment was initiated in a split plot design with three main and three sub-treatments using maize (Kanchan510) as the test crop. The main experimental treatments were: T1: Conventional Tillage (CT) +Two Intercultures (Two IC), T2: Low Tillage (LT) +Two Intercultures (Two IC) and T3: Low Tillage (LT) + Weedicide + One Interculture (One IC). The three sub treatments were, T1: 100% N through organic sources (compost), T2: 50% N through organic sources + 50% N through inorganic sources and T3: 100% N through inorganic sources. The results of the present study clearly revealed that the tillage treatments did not significantly influence most of the soil quality parameters except available S, microbial biomass carbon (MBC) and Mean weight Diameter of Soil Aggregates (MWD). When averaged over nutrient levels, among the tillage practices, conventional tillage + Two IC recorded the highest available S of 20.87 kg ha-1 . However, sub-sub treatments viz nutrient management significantly influenced the organic carbon (OC), available N, P S and boron, dehyrogenase assay (DHA), labile carbon (LC), bulk density (BD) and MWD. When averaged over tillage levels, the application of nutrients through inorganic sources recorded significantly highest available N (160.50 kg ha-1 ), P (30.67 kg ha-1 ) and K (207.87 kg ha-1) in soil. Finally, in terms of Relative Soil Quality Indices (RSQI), Low tillage + Two IC (0.87) and Low tillage + Weedicide + One IC (0.89) proved superior compared to Conventional Tillage + 2 IC (0.82). Similarly, when averaged over tillage levels, the order of performance of nutrient management treatments was:100% N through organic sources (0.93) > 50% N through organic sources + 50 % N through inorganic sources (0.84) > 100% N through inorganic sources (0.82). Though the interactions between tillage levels and nutrient management were not significant, but the combination of Low tillage practices with 100 % organic Source of nutrients was quite superior in maintaining relatively higher RSQI. Thus, the results of the present study and methodology used will be highly useful to different stake holders associated withland and soil quality management.