Control of legume pod borer,Maruca vitrataFab. and coreid bug,Clavigralla tomentosicollisStal on Cowpea,Vigna unguiculata(L.) Walp using different concentrations and spraying regimes of aqueous extracts from Neem,Azadirachta indica(A. Juss) seed

Abstract

The effect of three rates (5, 10 and 20% w/v) and different spraying schedules (2, 4 and 6 weekly applications) of aqueous neem, Azadirachta indica (A. Juss) seed extracts was tested on legume pod borers, Maruca vitrata Fab. and the coreid bugs, Clavigralla tomentosicollis Stal on cowpea under field conditions in two cropping seasons in the northern Guinea savanna of Nigeria. Legume pod borers (LPB) were better controlled at 20% and 6 applications of neem seed extract compared with other plant material treatments and the untreated check but its values were not significantly different to the synthetic insecticide treatment. Although, at similar rate of neem seed extract, its control of the coreid bugs was inferior to the synthetic insecticide treatment but was superior to 10% and 5% rates of neem seed extracts at all application schedules. Cowpea pods were adequately protected from damage by the pests and grain yields were significantly higher at 10 and 20% extract rates with four or six application schedu...