Differential responses of two cowpea (Virgina unguiculata L.Walp.) genotypes to pre-emergence herbicides in the savannah woodland and rainforest agroclimatic regions of Sierra Leone

Field trials were conducted in savannah woodland (Njala) and rainforest (Serabu) agroclimatic regions of Sierra Leone during 2016 second cropping season to assess different preemergence herbicides techniques that is efficient, cost effective environmentally safe cowpea production. The experiment consisted 20 treatments which included 2 genotypes (slipea 4 slipea 5) 10 weed control viz: butachlor 50% emulsifiable concentrate (EC), double force®, power force® applied as at 2, 6 L ha-1, respectively weedy check. laid out a strip-plot design arranged factorial system with three replications. results this study revealed the application ha-1 recorded highest phytotoxic effect, lowest dry weight, number pods per plant grain yield, total variable cost, gross net returns. Furthermore, EC closely followed by resulted maximum returns compared rest other techniques. Thus, it concluded was more economical, profitable beneficial than production Leone. Conclusively, relationship between phytotoxicity yield indicates higher lower effects chemicals.