Effect of Alternate Furrow Irrigation on Maize Productivity in Interaction with Different Irrigation Regimes and Biochar Amendment
Fatemeh Khalili, Fayaz Aghayari, Mohammad Reza Ardakani
Abstract
The alternate furrow irrigation (AFI) with suitable irrigation regime (IR) accompanied by biochar amendment can save irrigation water and lead to improvements in crop water productivity in arid areas. Therefore, a field experiment was conducted to investigate the impact of the AFI under three IRs (I100, I75 and I50 referring to meet 100, 75 and 50% of crop water requirement, respectively) and walnut feedstock biochar (0 and 10 t ha−1) on the yield and water productivity of maize compared to every furrow irrigation (EFI, conventional method) during the 2017 and 2018 growing seasons. The results indicated that mean grain yield in the AFI significantly decreased by 10.9, 12.6 and 21.6% at I100, I75 and I50, respectively, in comparison with EFI. This process might be associated with water stress and decreased 1000-grain weight. On average, the water productivity for grain yield under the AFI and using biochar significantly increased by 0.3 kg m−3 (17.1%) and 0.3 kg m−3 (17.1%), in comparison with EFI and nonusing biochar, respectively. The combination of IR of I75, AFI and using biochar leads to the maximized crop water productivity indexes (2.74 kg stover per m3 of water and 2.52 kg grain per m3 water), whereas there was no significant difference with combination of IR of I100, the AFI and using biochar. According to the results, effect of the AFI and using biochar on crop water productivity in the IR of I75 was higher than that in the IRs of I100 and I50. In general, when water was insufficient for full irrigation, the grain yield of maize in the AFI and using biochar was higher than those in the EFI and not used biochar, respectively.