Effect of conservation tillage on yield of spring wheat (Triticum aestivum L.) and soil mineral nitrogen and carbon content

Conservation farming practices using the least soil disturbance and straw-return benefits the crop agronomic attributes and soil nutrient accumulation. The four-year (2016-2019) research was conducted under randomized complete blocks design to explore the agronomic benefit of conservation tillage practices on wheat yield performance and on soil fertility parameters. The two straw treatments consisted of wheat straw-return to the notilled soil and straw incorporation into the conventionally tilled soil. The two tillage treatments were the no-tillage and conventional tillage control. These conservative tillage treatments were compared with the conventional tillage control. In comparison with conventional tillage, the conservation management practices of no-tilled soil, conventionally tilled soil, and no-tillage notably increased the yield by an average of 33, 26, and 18% respectively. Moreover, conservative tillage practices improved the soil nitratenitrogen, ammonium nitrogen and carbon contents in the 0-30 cm soil layer by 12, 9, and 15% respectively over conventional tillage, averaged across conventionally tilled soil, no-tilled soil, and no-tillage. The overall distribution of soil nitrate-nitrogen, ammonium nitrogen, and carbon in the 0-30 cm soil layer with regard to conventionally tilled, no-tilled soil, and no-tillage was greater than conventional tillage, based on Principal Component Analysis. We concluded that conservation tillage practices could replace conventionally tilled practice with respect to productivity, soil mineral nitrogen, and carbon accumulation benefits.