Impact of tillage and residue management on greenhouse gases emissions and global warming potential of winter wheat in a semi-arid climate

A two-year field study was carried out at the Indian Agricultural Research Institute New Delhi, from rabi 2020-21 to 2021-22, with the aim of examining the impacts of tillage and residue management on yield, greenhouse gases (GHGs) emissions, global warming potential (GWP) and carbon efficiency ratio (CER) of wheat in a split plot design. The results indicated that both tillage and residue management significantly influenced the grain and biomass yield of wheat. In comparison to conventional tillage (CT), no-tillage (NT) resulted in a substantial reduction of CO2-C emissions by 19.9%, while it led to a notable increase of N2O-N emissions by 11.6%. However, there was a notable and significant rise in GHG emissions with crop residue mulching, registering on an average 20.79% higher emissions compared to residue removal for both the years. The GWP was overall lower in case of NT as compared to CT plots. The highest CER was observed in NTR+ (3.07) during 2020-21 and in NTR0 (3.12) during 2021-22 due to lower CO2 emissions and higher C fixation in both years. Therefore, it may be recommended that wheat can be cultivated in a semi-arid environment with no tillage and residue mulching to provide a comparable yield in addition to lower GHG emissions and GWP and higher CER compared to the farmers’ practice of CT and residue removal.