A field experiment was conducted during the summer of 2023 at Tamil Nadu Agricultural University, Coimbatore, to evaluate the effects of various pre- and post-emergence herbicide combinations on weed dynamics and productivity in wet direct-seeded rice. The experiment employed a randomized block design with ten treatments replicated three times. The study assessed various weed management practices, including pre-emergence herbicides followed by post-emergence herbicides, pre-emergence herbicides followed by hand weeding, post-emergence herbicides followed by hand weeding, and the farmer's practice of two hand weedings. Key observations included weed flora, density, dry weight and crop parameters such as plant height, leaf area index, total dry matter production and yield attributes. The study found that, Echinochloa colona and Leptochloa chinensis were the dominant grasses, Cyperus difformis was the dominant sedge and Eclipta prostrata was the prominent broad-leaved weed. The pre-emergence application of pretilachlor + pyrazosulfuron ethyl effectively controlled grasses, sedges and broadleaf weeds, particularly at 20 DAS. The ready-mix formulation of pendimethalin followed by triafamone + ethoxysulfuron was most effective at 40 DAS and harvest, significantly reducing weed density and improving yield parameters.
