Assessment of selective herbicide mixtures for effective weed management in transplanted Kharif rice (Oryza sativa L.) in South Odisha

Weed infestation is one of the most important biotic factors, compromising 15-50% of grain yield in transplanted rice. Among different methods, the chemical method is the most effective one in terms of efficiency, time, cost, and labour. Single selective herbicide application is unable to suppress all categories of weeds, for which a herbicide mixture is the solution. To find out the best suitable combination of herbicides, an experiment was conducted during the Kharif season of 2024-25 at M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Odisha, India. The experiment was laid out in a randomized block design with ten treatments of weed management and three replications. The treatments consist of eight different combinations of herbicides, viz., bispyribac-sodium, fenoxaprop-p-ethyl, penoxsulam, triafamone, ethoxysulfuron, carfentrazone-ethyl, pretilachlor, and bensulfuron-methyl, along with weed-free (hand weeding at 20 and 40 days after transplanting) and weedy check. Among the herbicide mixtures, the bispyribac-sodium @25 g/ha + ethoxysulfuron @15 g/ha at 20 DAT (tank mix) was found to be the best performing herbicide registering the lowest weed density and dry weight; and highest crop growth parameters, yield parameters, grain yield (4.65 t/ha) and weed control efficiency (86.7%) compromising the grain yield of mere 4.2% as against 48.7% in the weedy check. The combination showed at par results with the weed-free check.