Department of Agricultural Biology, Faculty of Agriculture, University of Ruhuna, Mapalana, Kamburupitiya (Sri Lanka).
The effect of five botanicals, viz, pepper (Piper nigrum L.), annona (Annona reticulata L.), neem (Azadirachta indica A. Juss), chilli (Capsicum annurim L.) and lemon (Citrus limon L.) on oviposition, adult emergence and adult mortality of Callosobruchus maculatus F. was studied when cowpea, Vigna unguiculata L. Walp. seeds were treated with their dried leaf powders, except lemon where dried peels were used. Azadirachta indica gave significantly highest reduction in oviposition of C. maculatus (37.5%), followed by A. reticulata (39%) with 0.2 g concentration at 2 days after treatment (DAT). Again, A. indica significant reduction in adult emergence of C. maculatus (20.3%) with 0.2 g concentration at 30 DAT. In respect of adult mortality, 0.2 g of C. limon recorded highest mortality (8.3%) at 4 DAT and P. nigrum powder gave 8.25% mortality with 0.3 g of concentration, six days after treatment.
