Evaluation of different weed management practices for controlling purple nut sedge (Cyperus rotundus L.) on maize (Zea mays L.) yield in Malle District of South Omo Zone

The experiment was conducted at Malle district of South Omo zone during 2017 and 2018 main maize cropping season with objective of evaluating the effect of integrated weed management techniques for controlling Cyperus rotundus in the study area. In the experiment, the maize variety BH140 was used. Field experiments were conducted with four treatments by a randomized complete block design with four replications. The result indicated that the highest C. rotundus population was recorded from treatments with farmer practices while due to herbicidal action the initial emerged C. rotundus weed population was low on Dual Gold 960 EC treated plots; however, in the later stage of crop growth the weed type converted to broad leaved species which have huge impact on the yield of the crop. The highest grain yield was obtained from plots under double hand weeding while the lowest grain yield was recorded from Dual Gold 960 EC treated plots. This result implies that the double hand weeding help to reduce the weed population and improves the crop performance while single herbicide treatment only control C. rotundus and broad leave weed species but cause huge decline in grain yield. From the above results, it was concluded that hand weeding at 21 and 35 days after sowing gives higher yield in comparison to other treatments, so, this practice was recommended for the effective management of C. rotundus in Malle district.