Efficacy of selected herbicide mixtures for weed control in sugar cane

Abstract

SummaryThree trials were conducted over two cropping seasons, on portions of the production fields of the Nigerian Sugar Company sugar-cane estate, Bacita, to evaluate the efficacy of several herbicide mixtures for weed control in sugar cane using the varieties Co. 957 and Co. 1001. With a broad spectrum of weeds, early post-emergence applications of diuron + hexazinone (2·0 + 0·7 kg a.i./ha) followed by hexazinone + paraquat (0·5 + 0·3 kg a.i./ha) about 8 weeks after the first application gave satisfactory weed control that resulted in high cane yields. Addition of glyphosate to the mixture for the first application or its substitution for paraquat in the second application, or both, resulted in increased suppression of nutsedge. This was, however, more phytotoxic to the sugar-cane plants. Addition of pendimethalin to either diuron or hexazinone improved the control of grass weeds. Hexazinone-based mixtures were found to give longer-lasting weed control than the diuron-based mixtures. Both diuron and hexazinone were generally more selective on Co. 957 than on Co. 1001. The degree of weed infestation between 6 and 12 weeks after planting was inversely related to cane yield.