Yield and yield attributes of lowland rice as affected by weed control methods in Sudan savanna zone of Kebbi State Nigeria

Field experiment was conducted during 2019 rainy season at the Experimental/Seed Multiplication Farm of National Cereals Research Institute (NCRI), Rice Research sub-station, Gwadangaji, Birnin Kebbi, Kebbi State (latitude 12º 11’; longitude 12º 4’). The treatments consist of factorial combination of two level of Topstar spectrum 600 and 400 ml ha-1, two level of Cranstan spectrum 1250 and 800 ml ha-1; (pre-emergence and post-emergence herbicide), hoe weeding and a weedy check. The treatments were laid out in Randomized Complete Block Design (RCBD) and were replicated three times. Data were taken and subjected to analysis of variance (ANOVA) and means were separated using Duncan’s Multiple Range Test (DMRT). Result obtained revealed that, Topstar at the rate of 600 ml haˉ¹ produced significantly higher number of productive tillers, panicle length, 1000 grain weight and grain yield. Topstar show highest weed control than all other treatments. Weed cover score and weed dry weight significantly responded to weed control treatments. The result also shows that weedy check consistently recorded the highest value for weed cover and weed dry weight which was followed by plot treated with Cranstan at 800 ml haˉ¹. Topstar at 600 ml haˉ¹ is found to be the best pre-emergence spectrum in weed management in rice field.