Studies on the efficacy of some biorational insecticides against the banana weevil cosmopolites sordidus (Germar) (Coleoptera: Curculionidae)

Abstract

Biorat!onal insecticides obtained from tobacco, ash , urine, pepper and a concoction (mixture) were tested for their effect
on adult weevil mortality, repellence and oviposition. Weevil oviposition on corms treated with tobacco, urine and the
concoction was significantly reduced corn pared to oviposition on those treated with ash and pepper and on control corms.
Similarly, the mean number of weevils settling on corms treated with the concoction compared to controls was statistically
different for all the periods of the study. The mean number of weevils settling on corms treated with concoctions stored for
four weeks was significantly lower than to those settling on corms lreatcd with concoctions used either immediately or
stored for one to two weeks. The concoction showed limited residual activity.