Weed management is crucial and expensive step towards cowpea production. Field experiments were conducted during the wet season of 2019 and 2020 at the Research and Teaching farm of the Faculty of Agriculture, Bayero University Kano to evaluate the effectiveness and profitability of selected weed management using weedy check (control), hoe weeding at 3 and 6 weeks after sowing (WAS), metolachlor at 2.0 kg a.i.ha-1, imazethapyr at 3.0 kg a.i.ha-1, pendimethalin at 2.0 kg a.i. ha-1, pendimethalin at 3.0 kg a.i ha-1, pendimethalin 1.0 + imazethapyr 1.0 kg a.i.ha-1, metolachlor 1.5 + pendimethalin 1.5 kg a.i.ha-1, imazethapyr 1.0 + pendimethalin 1.0 kg a.i.ha-1 + SHW at 6 WAS, metolachlor 1.5 + pendimethalin 1.5 kg a.i.ha-1 + SHW at 6 WAS, metolachlor at 2.0 + SHW at 6 WAS, pendimethalin at 2.0 + Supplementary hoe weeding (SHW) at 6 WAS. Weedy check plots yielded significantly (P < 0.01) higher weed density and dry weight than hoe weeded plots at 3 and 6 WAS, Pendimethalin and Metolachlor each at 2.0 + SHW at 6 WAS, which produced lower density and biomass, albeit comparable to other herbicidal-treated plots across the two seasons. Similarly, the application of two hoe weeding’s at 3 and 6 WAS and Metolachlor and Pendimethalin at 2.0 + SHW at 6 WAS significantly resulted in producing higher branches, pods plant-1, pod yield and fodder yield than weedy check. The result of the profitability analysis shows that the highest and lowest gross margin was obtained under pendimethalin at 2.0 kg a.i.h-1 + SHW at 6 WAS (₦164,385/ha) and weedy check (₦28,020/ha), respectively. The average gross income (2019/2020) season was highest under hoe weeding at 3 and 6 WAS, which could be connected to high yield, however, its gross margin ratio (53%) decreased lower than treatments under pendimethalin and metolachlor each at 2.0 kg a.i.h-1 + SHW at 6 WAS (56% and 55% respectively) which is associated with labour cost. For efficient management of cowpea weeds in Nigerian Sudan savanna ecology, application of pendimethalin and metolachlor at 2.0 kg a.i.h-1 + SHW at 6 WAS could be recommended due to their financial and economic advantages.
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