The rice–wheat cropping system in the North West IGP is the backbone of food security in India. In the 1990s, due to the scarcity of resources, the traditional Crop Establishment (CE) method shifted from Conventional Till Puddle Transplanted Rice (CTPTR) to CT Direct Seeded Rice (CTDSR) and Zero-Till DSR (ZTDSR) in paddy; and in wheat, from Conventional Till Wheat (CTW) to Zero Till Wheat (ZTW), with residue retention in rice (RRR) or in both rice and wheat (RRRW). Shift in CE methods led to change in Weed Seed Bank (WSB) dynamics and ultimately affected the weed management practices. Review study showed that CTPTR-CTW and ZTDSR-ZTW (RRRW) record the highest seed bank (SB) of grasses, sedges and BLWs as total weeds, in general; and predominant weeds i.e., Echinochloa spp., Ammania baccifera, Commelina benghalensis and Digitaria sanguinalis, in particular. It also showed the higher species richness (D_Mg) and Shannon–Weaver (H’) indices. CTDSR-CTW and CTDSR-ZTW (RRR) show the lowest WSB and at par with Shannon–Weaver (H’) index; further, lowest species richness (D_Mg) under CTDSR-CTW. The average yield losses caused by weeds in different wheat growing zones ranged from 20 to 32%. Uncontrolled weeds in wheat caused 60.5% reduction in wheat grain yield under CT and 70% in ZT conditions. Potential solutions include a shift from intensive tillage to no or reduced tillage and/or from transplanting to direct-seeding. Zero tillage ameliorates the problem of delayed sowing as well as reduces weeds like Phalaris minor in wheat. Adoption of conservation agricultural practices reduces the intensity of soil manipulation thereby creates an unfavorable condition for weed seed germination, reduces the organic matter depletion and soil degradation. Reducing tillage may shift weed communities from annual dicots to grassy annuals and perennials. Surface residues lower average soil temperatures and may delay emergence of both crops and weeds. Germination and growth of small-seeded annuals will suffer from restricted light availability, physical growth barriers and potential allelopathic effects from surface of irrigation water, but with an associated yield loss of 14 to 25%. Nevertheless, water use efficiency (WUE) in the residue. Compared with conventional puddled transplanting; direct seeding of rice on raised beds had a 13 to 23% savings 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). Moreover, CT-TPR system, zero till direct-seeded rice (ZT-DSR) consumed 6%-10% less water with almost equal system productivity and demonstrated higher water pro-ductility.

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