Integrated weed management in wheat under conservation agriculture-based maize-wheat-mungbean system

A field experiment was conducted on integrated weed management in wheat (Triticum aestivum L.) under conservation agriculture-based maize (Zea mays L.)–wheat–mung bean [Vigna radiata (L.) R. Wilczek] system during the winter (rabi) season of 2020–2021 at the ICAR–Indian Agricultural Research Institute, New Delhi. The experiment was carried out in a split-plot design, with 4 main plots having different establishment techniques, viz. conventional tillage (CT)–wheat, zero tillage (ZT)–wheat, ZT–wheat with previous brown manuring in maize and stale seed bed (SSB)–ZT wheat; and 4 subplots, viz. unweeded check, weed-free check, 1 hand-weeding at 25 days after sowing (DAS) and clodinafop-propargyl (60 g/ha) + carfentazone (20 g/ha) as tank-mix at 25–30 DAS. The results revealed that, the yield attributes and yield of wheat were significantly influenced by the weed-management practices under different establishment techniques. The establishment method, ZT–wheat with brown manuring in previous maize resulted in the highest crop yield, followed by SSB–ZT wheat. Among the weed-management options, clodinafop-propargyl (60 g/ha) + carfentazone (20 g/ha) as tank-mix at 25–30 DAS resulted in the highest growth, yield attributes and economics, which remained at par with hand-weeding. The highest grain yield (4.85 t/ ha), straw yield (9.03 t/ha), and biological yield (14.32 t/ha) were recorded under ZT–wheat, with brown manuring in previous maize. A 16.5, 7.3 and 9.94% increase in grain, straw and biological yield, respectively, was recorded with clodinafop-propargyl (60 g/ha) + carfentazone (20 g/ha) as post tank-mix 25–30 DAS over unweeded check. The ZT–wheat showed 51.4% higher net returns over CT, followed by ZT–wheat and SSB–ZT wheat which showed 22.1 and 19.2% higher values, respectively, over CT. The highest benefit : cost (B : C) ratio was found in weed-free check which showed 21.9% higher value over unweeded check.