Deep tillage and irrigation impacts on crop performance of direct seeded rice–wheat cropping system in north-west India

Abstract

The subsurface compact layer found in medium- to coarse-textured soils of rice-grown areas hampers the root growth of crops. Moreover, the puddled transplanted rice is being faced by water and labour shortages in the region. It is thus imperative to study the effects of deep tillage and irrigation regimes on crop performance of direct seeded rice (DSR) and wheat. A 2-year field experiment was conducted during 2016–2017 and 2017–2018 in a sandy loam soil to investigate the effects of deep tillage and irrigation regimes on crop performance of DSR–wheat cropping system. There were two irrigation regimes both in DSR [irrigation to DSR at 4-day (4-d) and 8-day (8-d) interval] and in wheat crop [based on irrigation water to pan evaporation ratio of 1.0 (I1.0) and 0.5 (I0.5)] in main plots, with three tillage treatments, viz. (1) conventional tillage in DSR + conventional tillage in wheat (DSRCT-WCT), (2) deep tillage before the sowing of DSR during first season + conventional tillage in wheat (DSRDT1-WCT) and (3) deep tillage before the sowing of DSR during both the seasons + conventional tillage in wheat (DSRDT2-WCT) in subplots. The root growth was higher in plots with deep tillage in comparison with plots with conventional tillage. The increased root growth under deep tilled conditions attributed to higher grain yield of DSR (18.3 and 12.6% during 2016 and 2017, respectively), wheat (6.6 and 7.9% during 2016–2017 and 2017–2018, respectively) and cropping system a whole (12.6 and 10.9% during 2016–2017 and 2017–2018, respectively). Though the tillage treatments were imposed before the sowing of DSR, they had residual impact on the following wheat crop. Deep tillage during both the seasons (DSRDT2-WCT) had not any significant influence on the grain yield of DSR, wheat and cropping system as a whole in comparison with deep tillage only once in 2 years (DSRDT1-WCT).