Effects of Different Weed Control Measures on Leaf Area Index and Yield of Three Varieties of Rice under Two Planting Methods

Abstract

Field trials were conducted during the 2005, 2006 and 2007 rainy season at Irrigation Research Station, Kadawa situated in Sudan savannah agro – ecological zone, Kano state, Nigeria to investigate the effects of different weed control measures on leaf area index and yield of three varieties of lowland rice under two planting methods. The trials were laid out in split – plot design and replicated three times with factorial combination of two planting methods and three varieties in the main plots and weed control treatments in the subplots. The result revealed that transplanting of rice increased leaf area index in 2006, 2007 and mean value for the three years 12WAS / T. Transplanting also resulted in higher paddy yield than direct seeding in 2006 and mean value for the three years. FARO 52 rice variety had significantly higher leaf area index than FARO 50 and FARO 44 in 2005 cropping season. FARO 52 had higher yield in 2006 and the mean value for the three years compare to the other two varieties. Application of pre – emergence oxadiazon at 1.0 Kg per hectare followed by post – emergence piperophos plus propanil at 1.5 Kg per hectare applied at 5 WAS / T gave the highest mean yield for the three years closely followed by hand-pulling weed control measure compared to the weedy check that gave the least mean paddy yield. Application of pre – emergence oxadiazon at 1.0 Kg per hectare followed by post – emergence piperophos plus propanil at 1.5 Kg per hectare applied at 5 WAS / T in transplanted FARO 52 gave the highest mean yield of 5.5 tonnes per hectare for the three years than  weedy check that gave the least mean paddy yield of 2.6 tonnes per hectare. It can be concluded that transplanting of FARO 52 rice variety and combined application of pre-emergence application of oxadiazon at 1.0 kg per hectare followed by post-emergence piperophos plus propanil at 1.5 kg per hectare is therefore recommended as the economically viable integrated package for lowland rice production in the Sudan Savanna agro-ecological zones.