Deep tillage and irrigation impact on soil water balance and water productivity of maize-wheat cropping system in north-west India

Abstract

ABSTRACT The subsurface compact soil layer hampers the root growth of crops and affects the crop water productivity. It is imperative to study the deep tillage impact on soil water balance and water productivity of maize-wheat cropping system. A two-year (2016–18) field experiment was conducted with two irrigation regimes in main plots based on irrigation water to pan evaporation ratio 1.2 (I1.2) and 0.8 (I0.8) in maize and 1.0 (I1.0) and 0.5 (I0.5) in wheat; and three tillage treatments in subplots (i) conventional-tilled maize followed by conventional-tilled wheat (MCT-WCT), (ii) deep tillage before the sowing of maize during first season followed by conventional-tilled wheat (MDT1-WCT) (iii) deep tillage before the sowing of maize during both the seasons followed by conventional-tilled wheat (MDT2-WCT). The irrigation water input was lower by 75 mm and 225 mm in I0.8/I0.5 than I1.2/I1.0 during 2016–17 and 2017–18, respectively. The evapotranspiration of maize and wheat was significantly higher with frequent irrigation regime. The water productivity was significantly higher under I0.8/I0.5 than under I1.2/I1.0 in 2017–18. The deep tillage helped in increasing the water productivity of maize-wheat system, the effect being similar with respect to frequency of deep tillage.