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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Conventional tillage and crop establishment methods such as puddled transplanting in the rice–wheat (Oryza sativa L.–Triticum aestivum L.) system in the Indo‐Gangetic Plains (IGP) require a large amount of water and labor, both of which are increasingly becoming scarce and expensive. We attempted to evaluate alternatives that would require smaller amounts of these two inputs. A field experiment was conducted in the IGP for 2 yr to evaluate various tillage and crop establishment systems for their efficiency in labor, water, and energy use and economic profitability. The yields of rice in the conventional puddled transplanting and direct‐seeding on puddled or nonpuddled (no‐tillage) flat bed systems were equal. Yields of wheat following either the puddled‐transplanted or no‐tillage direct‐seeded rice were also equal. Normally, puddled transplanting required 35 to 40% more irrigation water than no‐tillage direct‐seeded rice. Compared with conventional puddled transplanting, direct seeding of rice on raised beds had a 13 to 23% savings of irrigation water, but with an associated yield loss of 14 to 25%. Nevertheless, water use efficiency (WUE) in the rice–wheat system was higher with direct‐seeded rice (0.45 g L−1) than with transplanted rice (0.37–0.43 g L−1). In Year 1, no‐tillage rice–wheat had a higher net return than the conventional system, whereas in Year 2 the net returns were equal. The study showed that the conventional practice of puddled transplanting could be replaced with no‐tillage‐based crop establishment methods to save water and labor. However, the occurrence and distribution of rainfall during the cropping season had considerable influence on the savings in irrigation water.

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