Influence of Weed Management Practices on Growth, Yield Attributes and Yield of Wet- Direct Seeded Kharif Rice (Oryza sativa L.)

Abstract

Two-year field experiment was conducted during the kharif seasons of 2022 and 2023 (July-November) at the University of Calcutta Agricultural Experimental Farm, Baruipur, West Bengal, using the rice variety ‘Ajit’ (IET 22066). The experiment was laid out in a Randomized Complete Block Design (RCBD) with nine treatments and three replications, comprising T₁-Pendimethalin 30 EC (1000 g a.i. ha-1) as pre-emergence (PE) at 3 DAS, T₂-Pretilachlor 30.7 EW (500 g a.i./ha) as PE at 3 DAS, T₃-Oxadiargyl 80 WP (80 g a.i./ha) as PE at 3 DAS, T₄–Pyrazosulfuron-ethyl 10 WP (25 g a.i./ha), T₅-Bispyribac-sodium 10 SC (25 g a.i. ha-1) as post-emergence (POE) at 20 DAS, T₆-Triafamone 20% + Ethoxysulfuron 10% WG (150 g a.i. ha-1) as POE at 20 DAS, T₇-Pretilachlor 30.7 EW (500 g a.i. ha-1) as PE at 3 DAS + Bispyribac-sodium 10 SC (25 g a.i. ha-1) as POE at 20 DAS, T₈-Hand weeding at 20 and 40 DAS, and T₉-Unweeded control. The pre-germinated seeds were broadcasted on wet-puddled soils during the third week of July in mid-upland condition. The soil was fertile with clay loam in texture having pH of 6.0. The treatment T₈-Hand weeding at 20 and 40 DAS showed lowest weed biomass-(25.67, 21.22 and 23.44) g m-2 at 90 DAS and weed density-(25.09, 20.48 and 22.79) m-2. Similar treatment performed best regarding growth parameters, yield attributes and yield of (4.53 t ha-1) grain yield and (6.65 t ha-1) straw yield during the experimental years. Herbicidal treatment T₇-Pretilachlor 30.7 EW (500 g a.i. ha-1) as PE at 3 DAS + Bispyribac-sodium 10 SC (25 g a.i. ha-1) as POE at 20 DAS was the second-best treatment after manual weeding in terms of weed control and yield performance. The control plot T9 indicated lowest yield due to not adoption of any weed management practices.