Abstract:
A field experiment was conducted at the Faculty of Agricultural Sciences Farm, at El Selaim, University of Dongola, Sudan during 2010/2011 and 2011/2012 seasons, to determine the magnitude of yield losses in common bean due to weed competition, and to evaluate the effects of two pre-emergence herbicides oxyfluorofen and pendimethalin. The results showed that unrestricted weed growth reduced common bean yield by 47.01 –54.44%. All herbicides, irrespective of the rate used, had significantly reduced weed biomass compared to the weedy check. The herbicides were more effective in controlling grassy weeds. Pedimethalin effected 77.3 - 98.2% and 80.4 - 94.9% control of grassy weeds in 2010/2011 and 2011/2012 respectively. Oxyfluorofen control of grasses, on other hand, effected 68.9 to 96.5% and 74.9 to 96.4 in 2010/2011 and 2011/2012 respectively. Pedimethalin at 0.5 kg a.i /fed produced the minimum weed index of 0.8 and 18.91 and attained crop yield (997.32 and 1140.37 kg/fed) comparable to the weed free treatment.