Water Use Efficiency Differences in Maize Varieties under Every Furrow and Alternate Furrow Irrigation

Abstract

Water-use efficiency (WUE) differences of selected maize varieties under alternate and every furrow irrigation were investigated in a split-plot design trials with three replicates. Alternate furrow (AFI) and Every furrow irrigation (EFI) were main treatments and twenty maize varieties were sub-treatments. Plots were 64 m2 with one maize seed per station spaced at 0.25m apart. Crop water use results indicated that EFI consumed more water than the AFI. The AFI reduced crop water consumption by 38 - 45% compared to EFI.  Differences were also prominent in maize varieties’ response to AFI. Late maturing maize varieties proved to have minor yield reduction with AFI compared to early and medium maturing maize varieties. WUE (kg m-3) differed with irrigation water application strategy (P<0.001). AFI had high WUE. A combination of AFI with selection of water efficient maize varieties was a good strategy for improving WUE. The AFI is a promising furrow irrigation water management strategy for water saving. According to farmers experience at five irrigation schemes and on station research, it was concluded that AFI is one of the climate smart irrigation technique that farmer can easily adopt and apply as it saves labour, time water whilst reducing conflict for water among irrigators. It was recommended that AFI be applied fully on early and medium maturing maize varieties within an irrigation interval of 7 days. For late maturing maize varieties, AFI technique should be applied from initial stage to mid - stage (up 55 days from planting) then apply EFI at tasselling and silking stages to reduce water stress at this critical stage.