Effect of Integrated Weed Management Practices on Weed Flora, Yield and Monetary Returns of Rice (Oryza sativa L.)

Abstract

Rice (Oryza sativa L.) holds an indispensable position as the most important staple food crop worldwide, serving as the primary food source for nearly 60% of the global population. Weeds are a major hindrance to rice cultivation, especially in the critical growth stages when they compete with rice for essential resources like nutrients, light, and space. Weeds contribute to 45% of the total annual agricultural production losses in India, surpassing other agricultural pests like insects and diseases. The critical period for rice-weed competition typically occurs during the vegetative phase of rice, and effective weed management during this time is crucial for maximizing rice productivity. A field experiment on “Effect of integrated weed management practices on weed flora, yield and monetary returns of rice (Oryza sativa L.) was conducted in rice during kharif season in 2022 and 2023 on sandy loamy in texture available nitrogen (225. kg ha-1), available phosphorus (14.70 kg ha-1) and potassium (170.82 kg ha-1) with slightly alkaline in reaction (pH 7.5).at crop research center of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut. Experiment was laid out in a randomized block design with three replications. Studies were conducted with twelve treatments viz., Weedy check T1, Weed free T2, Farmers practices (one hand weeding 40 DAT) T3, Pyrazosulfuron 150 g a.i. ha-1 (Pre- emergence) T4, Pyrazosulfuron 150 g a.i. ha-1 (Pre emergence) + one hand weeding 40 DAT T5, Bispyribac Sodium @ 25 g a.i. ha-1 (post-emergence) T6, Bispyribac Sodium 25 g a.i. ha-1 (post-emergence) + one hand weeding 40 DAT T7, Ethoxysulfuron @20g a.i. ha-1 (pre- emergence) T8, Ethoxysulfuron @20g a.i. ha-1 (pre- emergence) + one hand weeding 40 DAT T9, Penoxsulam 22 g a.i. ha-1 (post emergence) T10, Penoxsulam 22 g a.i. ha-1 (post emergence) + One hand weeding 40 DAT T11, Pyrazosulfuron 150 g ai.ha-1 (pre- emergence) + Penoxsulam 22 g a.i. ha-1 post- emergence + One hand weeding 40 DAT T12. The predominant weed flora observed in the experimental plot were Echinochloa colonum (L.) and Echinochloa crusgalli (L.) among the grassy weeds, Echinochloa colona (L.), Echinochloa crusgalli (L.) and Dactyloctenium aegyptium (L.) among broad leaved weeds Commelina benghalensis, Phyllanthus niruri and Caesulia axillaris and sedges weeds Cyprus iria and Cyprus rotundus. Among the herbicide maximum weed control efficiency ( 73.24 & 73.20) and total nutrient uptake kg ha-1 at 90 DAT (94.6 & 101.8 nitrogen, 24.9 & 27.5 and 108,6 & 116.2 ), higher growth attributes as reflected by taller plants ( 111.4 & 113.1), higher no. of tillers m-2 ( 312 & 325.5), higher dry matter accumulation g m-2 (1285.8 & 1300.4), LAI (6.32&6.51)) recorded at harvest was observed in Pyrazosulfuron 150 g ai.ha-1 (pre- emergence) + Penoxsulam 22 g a.i. ha-1 post- emergence + One hand weeding 40 DAT was found at par with Penoxsulam 22 g a.i. ha-1 (post emergence) + One hand weeding 40 DAT and Pyrazosulfuron 150 g a.i. ha-1 (Pre emergence) + one hand weeding 40 DAT significantly higher than the rest of treatments. as also noticed by (Yadav et al., 2011). Yield attributes and yields viz. effective tillers m-2 (284.5 & 296), number of filled grains panicle-1 (90 & 92), test weight (20.3 & 21.1 g), grain yield (46.8 & 48.5 q ha-1) and straw yield (70.8 & 73.1 q ha-1) , Mean increasing grain yield weeding was 45.7 and 39.6 per cent over weedy check during both the year and higher gross return 120800.4 & 125120.5Rs ha-1 ) net return of (74770.4 & 78194.5 Rs ha-1 ) with B:C ratio of (2.62 & 2.67 ) were also higher during both the year with the application of Pyrazosulfuron 150 g ai.ha-1 (pre- emergence) + Penoxsulam 22 g a.i. ha-1 post- emergence + One hand weeding 40 DAT followed by Penoxsulam 22 g a.i. ha-1 (post emergence) + One hand weeding 40 DAT and Pyrazosulfuron 150 g a.i. ha-1 (Pre emergence) + one hand weeding 40 DAT . Similar result was also put forward by Prakash et al. (2014). Thus, the rice crop grown with application of Pyrazosulfuron 150 g a.i. ha-1 (pre-emergence) + Penoxsulam 22 g a.i. ha-1 (post-emergence) + One hand weeding had attained higher weed control efficiency, nutrient uptake, better growth attributes (plant height, no. of tiller, dry matter accumulation LAI), yield attributes (effective tillers, , grains per panicle, test weight), yield, fetched higher net returns with higher B:C ratio.