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 (I_1.2) and 0.8 (I_0.8) in maize and 1.0 (I_1.0) and 0.5 (I_0.5) 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 I_0.8/I_0.5 than I_1.2/I_1.0 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 I_0.8/I_0.5 than under I_1.2/I_1.0 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.

摘要

地下致密的土壤层阻碍了作物的根系生长并影响作物的水分生产力。研究深耕对玉米-小麦种植系统土壤水分平衡和水分生产力的影响势在必行。一项为期两年（2016-18 年）的田间试验在主要地块进行了两种灌溉方式，基于灌溉水与锅蒸发比 1.2 (I _1.2 ) 和 0.8 (I _0.8 ) 在玉米和 1.0 (I _1.0 ) 和 0.5 ( I _0.5 ) 在小麦中；和子地块中的三种耕作处理（i）常规耕作的玉米，然后是普通耕作的小麦（MCT-WCT），（ii）在第一季玉米播种前深耕，然后是普通耕作的小麦（MDT ₁-WCT) (iii) 在两个季节玉米播种前深耕，然后是常规耕作小麦 (MDT ₂ -WCT)。在 2016-17 和 2017-18 期间，I _0.8 /I _0.5的灌溉水输入量分别比 I _1.2 /I _1.0低 75 mm 和 225 mm 。玉米和小麦的蒸散量在频繁灌溉条件下显着增加。_{2017-18 年，I 0.8} /I _0.5下的水生产率显着高于I _1.2 /I _1.0下。深耕有助于提高玉米-小麦系统的水分生产力，其效果与深耕频率相似。