Effect of Weed Management Methods on the Growth and yield of Turmeric in Metu, Illubabor, Ethiopia

A field experiment was carried out at Metu Research Sub Center to determine the best weeding practice for turmeric under Metu condition. The experiment was carried out between 2010 and 2012 cropping seasons. Turmeric was subjected to nine weeding regimes using randomized complete block design with three replications The result showed that the major weeds recorded were: Gyzotia scabra., Nicandra physaloidesspp./ Commelina spp., Bidens Polynchyma, Caylusia abyssininca and Ageratum conyzoides. The result also reveled that turmeric rhizome yield was highly significantly (p<0.1) affected by weeding regimes . As hand weeding frequency increased turmeric yield also increased. The result reveled that one early hand weeding applied between 30 and 45 days after planting was critical for high yield of turmeric When the first hand weeding was delayed up to 60 days from planting yield of turmeric was reduced tremendously. However, the result showed that by mulching turmeric at planting the first hand weeding can be delayed up to 60 days without yield affected. Mulching turmeric at planting followed by two hand weeding at 60 and 90 days gave high yield compared with the with the treatment where the first hand weeding was applied at 60 days. Similarly, hand weeding at 30 and 60 days followed by mulching once also gave comparable yield with the weed free treatment. In addition, the result also revealed that mulching at planting enhanced the fast germination and emergence of turmeric compared with none mulched turmeric. On the other hand, the result also showed that turmeric was poor competitor of weed competition that it required to be free of weeds throughout the season.. The highest weed biomass was recorded from the control treatment and when weeding was totally ignored yield reduction as a result of uncontrolled weed growth amounted 98.7 % under Metu condition Keywords: Weed management, Turmeri