Deterrent effect of crude extract from mycelia toxin of Verticillium lecanii on sweet potato whitefly,Bemisia tabaci

The crude extracts from mycelia toxin of Verticillium lecanii(Zimm.)viegas strain Vp28 were gained after extractions with organic solvent and vacuum concentration.and the deterrent effect of the crude extracts on the adults of Bemisia tabaci was tested.The results showed that the crude extract from mycelia toxin of V.lecanii strain Vp28 possessed deterrent effect on adults of B.tabaci under 2000-6000 diluted concentration.and the deterrent rate dropped linearly with the decrease of the applied concentration of crude extracts.