Effect of weed management on weeds and grain yield of haricot bean

Weeds are one of the major constraints limiting haricot bean productivity and production. Field experiments were conducted on the effect of weed managements on weeds and grain yield of haricot bean (Phaseolus Vulgaris L.) at Melkassa Agricultural Research Center from 2011 - 2013. The objective was to determine the effect of weed managements, varieties and their interaction on weeds and grain yield. The experiment was laid out split plot arrangement using randomized complete block design with three replications. Treatments were s-metolachlor at the rate of 0.96 kg ha-1, glyphosate at the rate of 1.08 kg ha-1, integration of each herbicide with hand-weeding at 45 days after sowing, twice hand-weeding at 25 and 45 day after sowing and un-weeded check. Nicandra physalodes, Xanthium strumarium and Argemone ochroleuca were the dominant weed species. Weed density and dry matter weight were significantly influenced by weed managements. The highest (129.50 m-2) and the lowest (69.50 m-2) weed density were recorded from weedy check and integration of s-metolachlor at the rate of 0.96 kg ha-1 and hand-weeding. Comparison of weed managements showed that the lowest (114.72 gm-2) weed dry matter was recorded from application of s-metolachlor with hand-weeding at 45 days after sowing while the highest (349.50 gm-2) weed dry matter was obtained from weedy check. The highest (67.17%) weed control efficiency was obtained from integrated use of s-metolachlor with supplementary hand-weeding. The effect of variety, weed managements and their interaction showed significant difference (