Rice-wheat {Oryza sativa L-Triticum aestivum L.) rotation is the major production system in Asia, covering about 18 million ha. Conventional practice of growing rice (puddled transplanting) and wheat (conventional till, CT) deteriorate soil physical properties, and are input-and energy-intensive. Zero-tillage (ZT) along with drillseeding have been promoted to overcome these problems. A 7-yr permanent plot study evaluated various tillage and crop establishment (CE) methods on soil physical properties with an aim to improve soil health and resourceuse efficiency. Treatments included transplanting and direct-seeding ot rice on flat and raised beds with or without tillage followed by wheat in CT and ZT soil. Bulk density (D|j) of the 10-to 20-cm soil layer was highest under puddled treatments (1.74-1.77 Mg m"') and lowest under ZT treatments (1.66-1.71 Mg m"'). Likewise, soil penetration resistance (SPR) was highest at the 20-cm depth in puddled treatments (3.46-3.72 MPa) and lowest in ZT treatments (2.51-2.82 MPa). Compared with conventional practice, on average, water-stable aggregates (WSAs) > 0.25 mm were 28% higher in ZT direct-seeding with positive time trend of 4.02% yr~'. Infiltration was higher (0.29-0.40 cm h~') in ZT treatments than puddled treatments (0.18 cm h"'). The least-limiting water range was about double in ZT direct-seeding than that of conventional practice. Gradual improvement in soil physical parameters in ZT system resulted in improvement in wheat yield and is expected to be superior in longrun on system (ricc+wheat) basis. Further research is needed to understand mechanisms and requirements of two cereals with contrasting edaphic requirements in their new environment of ZT direct-seeding.

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Rice (Oryza sativa L.)–wheat (Triticum aestivum L.) is the major cropping system occupying 13.5 million ha in the Indo‐Gangetic Plains of South Asia. Conventional‐tillage practices are resource and cost intensive. A 7‐yr study evaluated six treatments (T) involving three tillage methods and two rice establishment methods on crop yield, water productivity, and economic profitability in a rice–wheat rotation. Average rice yields in the conventional practice of puddling and transplanting without (T1) and with (T2) mid‐season alternate wetting‐drying were highest (7.81–8.10 Mg ha−1) and increased with time (0.26 Mg ha−1 yr−1) in T2. Compared to T1, rice yields in direct drill‐seeding with zero‐tillage averaged 16% lower on flat (T5) and 43% lower in raised beds (T3). Rice yield in raised beds (T3 and T4) decreased with time (0.14–0.45 Mg ha−1 yr−1). Conversely, wheat yielded 18% higher after zero compared to conventional‐tillage. Treatment 2, despite low soil matric potential during vegetative development, had higher water productivity with 25% less water use compared with T1 and 19% less compared with other treatments. Conventional‐tillage and crop establishment practices had higher net cash return in rice but in wheat it was higher with zero‐tillage. Overall, T2 and T5 had the highest net returns (∼1225US$) and T3 and T4 had the lowest (747–846 US$) in the rice–wheat system. Zero‐tillage on flat beds (T5), however, would conceivably be more sustainable than the conventional T2 in the long‐run. Yields of zero‐tillage with direct‐seeding of rice on flat beds (T5) must improve before adoption occurs.

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