Question: query regarding management of insect infestation on cowpea. 
Answer: please use any one of the following insecticide 3times @ 4 days inteval in the evening time in the absence of rain.

organic insecticide- dada supar 1ml/liter of water
                                           neem oil 5ml/liter of water
                                            azarirachtin 2ml/liter of water

chemical insecticide- flubensik 1ml/liter of water
                                             actara 3g/10liter of water