Use of pesticide in cowpea production has remained on the front burner of discuss on sustainable cowpea production due to prevailing threat of insect pests, increasing cost of chemicals, threat of environmental hazard and concern for food safety. This study therefore evaluated different spraying regimes on production of two cowpea varieties in the humid South West Agro-ecologies with the aim of recommending optimum spraying regime for cowpea production in the zone. Agronomic data were collected from trials conducted in 2020 and 2021 in Outstations representative of the broad agro-ecologies of South West Nigeria. The data were subjected to partial budget and Marginal Rate of Return Analyses. Results show varying potential of the cowpea varieties and spraying regime across locations. Ife brown cowpea can be profitably produced under forest agro-ecologies (Ibadan) with 3 spraying regimes at moderate application rate of 200 litres per hectare. In the derived savannah, Ife brown and IT2246 varieties are profitable with 4 spraying regimes at moderate application rate of 200 litres per hectare while planting of Ife brown with 2 regimes of spraying at moderate pesticide application rate of 200 litre per hectare is profitable for the southern guinea savannah agro-ecologies.

Keywords: Cowpea; insecticide; profitability; insect pest; marginal