Abstract
Okra productivity is reduced by weed interference. Farmers rely on expensive and highly labour intensive manual weeding. Herbicides reduce labour involvement and cost of weed control. Few herbicides tagged for okra production are scarce. The key objectives of this study are to determine the tolerance of okra to some widely used herbicides and evaluate the growth performance of okra in the selected herbicides. The average phytotoxicity levels of each of the herbicides for 2013 and 2014 field trials were in the order of zero in pendimethalin at 2.0 kg a.i./ha, 4.2 in metholachlor+atrazine at 2.64 kg a.i./ha and 5.5 in atrazine at 3.0 kg a.i./ha, on a 0-10 scale. Okra stands establishment was (95.2%) in pendimethalin and (93.1%) in hoe-weeded plots, these were significantly greater than 62.8% and 56.9% obtained in metholachlor+atrazine at 2.64 kg a.i./ha and atrazine at 3.0 kg a.i./ha, respectively. Hoe-weeded plots had shoot dry weight of 7.9 g/plant which was similar to 7.3 g/plant obtained in pendimethalin treated plots; these were significantly greater than 4.1 g/plant obtained in plots that received atrazine. Pendimethalin which caused no phytotoxic effect on okra and provided enhanced stand establishment and growth comparable with hoe-weeded should be listed for okra production.