Abstract:
Weeds constitute a major biotic constraint that limits wheat production (Triticum aestivum L.) in Sudan. A herbicide experiment was conducted during two consecutive winter seasons of the years 2009/2010 and 2010/2011 at Elkarwat scheme, Dongola Locality, Northern State, Sudan to determine the magnitude of yield losses due to weed interference and to evaluate herbicidal efficacy of 2,4-D, Clodinafop-propargyl and their tank mixtures in wheat. Weeded and unweeded checks were included for comparison. 2,4-D at all rates gave consistent and effective control of broad-leaved weeds throughout the growing season, but its activity against grassy weeds was poor. Clodinafop-propargyl at both rates gave good control of grassy weeds, but its activity against broad-leaved weeds was poor. The herbicides in tank mixtures gave consistent and effective control of both grassy and broad-leaved weeds throughout the season. The highest grassy and broad-leaved weeds control was achieved by the herbicides tank mixtures. A significant weed control was achieved in terms of total weed biomass reduction with all herbicides rates and their tank mixtures compared to the weedy check. The highest weed biomass reduction was achieved by 2,4-D at 6.8 kg a.i./fed. in tank mixture with clodinafop-propargyl at 0.3 and 0.4 kg a.i./fed. Combined analysis of both winter seasons indicated that unrestricted weed growth significantly reduced wheat grain yield by 68.94% compared to the weed free treatment. The results showed that among all herbicides treatments the highest grain yield was achieved by 2,4-D at 6.8 kg. a.i/fed., in tank mixture with clodinafop-propargyl at 0.4 kg. a.i/fed., which gave a total grain yield comparable to weed free treatment.
