Efficacy and economics of integrated weed management in okra (Abelmoschus esculentus (L.) Moench)

Weed management is one of the most important and expensive steps in okra production. Field experiments were therefore conducted in the early and late wet seasons of 2015 to evaluate the effectiveness and profitability of weed management using hoe weeding, herbicides or their combination in okra production. Propaben or butachlor at 2.0 kg a.i. (active ingredient) ha–¹ followed by (fb) supplementary hoe weeding (shw) at 6 weeks after sowing (WAS) significantly (P < 0.05) reduced weed density and biomass with subsequent increase in okra fruit yield similar to three hoe weedings and better than two hoe weedings or either herbicide applied alone in both early and late wet seasons. Although three hoe weedings provided the highest okra fruit yield (3590 and 4102 kg ha–¹) and total revenue ($991.7 and $1699.7 ha–¹), the gross margin ($186.4 and $931.6 ha–¹) and cost-benefit ratio (0.2 and 1.2) obtained were lower than those obtained with herbicide treatments. Highest gross margin ($470.8 and $1224.9 ha–¹) and cost-benefit ratio (1.2 and 3.0) in the early and late wet seasons, respectively, were achieved with propaben at 2.0 kg a.i ha–¹ fb shw at 6 WAS. The results of this study suggest that integrated weed management with propaben followed by supplementary hoe weeding will improve weed control, productivity and profitability of okra. Multiple hoe weeding, however, did not guarantee highest profit but rather increased the cost of production.