Investigation of tannin crude extract from cassava leaves for mealy bug control

Abstract

Different concentrations of tannin crude extract from cassava leaves were used for direct spraying, dipping, choice and no-choice repellent test for controlling cassava mealy bug (Pseudococcus jackbeardsleyi Gimpel and Miller). By direct spray method, it was showed that tannin crude extract could not kill cassava mealy bug as insecticide but remarkably repelled mealy bug. Dipping method at 1,500 mg/l tannin concentration could only kill the mealy bug of 7.4% and seemed to decrease plant damage of 32.52% when compared with control. Field experiment revealed that spraying with 1,000 mg/l tannin extract concentration could keep cassava clean, less damaging of mealy bug as well as cassava could promote new apical bud, axially growth and straight trunk. It was wondering that extract from cassava leaves could be used as cassava mealy bug repellant. © 2013 American Scientific Publishers.