Some factors affecting butachlor phytotoxicity and performance in wet-seeded rice

Abstract

Two experiments were conducted to determine the effect of formulation, rate, time and method of butachlor [N-(buthoxymethyl)-2-chloro-N-(2,6-diethylphenyl) acetamide] application, and flooding time on herbicide selectivity, weed control, and yield of wet-seeded rice (Oryza sativa L.). Early flooding reduced crop stand and plant height in butachlor-treated plots. Application of butachlor at 6 days after seeding (DAS) gave poor weed control at all flooding times. Formulation, rate, and method of application had little effect on weed control and rice yield when butachlor was applied at 3 days before seeding (DBS). Weed control was better and yields higher in plots treated at 3 DBS than in plots treated at 6 DAS. Because of better weed control, plots treated with emulsifiable concentrate gave higher yields than plots treated with granule when application was at 6 DAS.