Irrigated rice is subject to interference caused by biotic and abiotic factors. Among the former, weeds are the main causes of decreased productivity, directly interfering in rice yield. The objective of this study was to evaluate the effect of irrigation starting times, application times and penoxsulam rates on the yield components of irrigated rice, cultivar Qualimax 1. The experiment was installed in the field, in a randomized block design with split plots and four replications. The plots allocated application dates (early and late) of Penoxsulam, and the subplots the starting times of irrigation (1, 15 and 30 days after herbicide application - DAT) and the split-split herbicide doses (0, 24, 36, 48 and 60 g ha-1). The highest grain yield was obtained by applying penoxsulam at the rates of 36 g ha-1 or above, regardless of the application time, and when early irrigation was carried out. The anticipation of irrigation generally increases the yield components of rice cultivar Qualimax 1. The application of penoxsulam at equal doses or higher than 36 g ha-1, regardless of application dates or flood, do not change the yield components of irrigated rice.
Cyperus esculentus; chemical control; Echinochloa sp.; Oryza sativa
