Effects of Vitex negundo L. leaf extracts on adult emergence of the stored product pest, Tribolium castaneum H. (Coleoptera: Tenebrionidae)

Effect of Vitex negundo leaf extracts prepared in petroleum ether (VPE) and methanol (VME) was observed on adult emergence of Tribolium castaneum during 25, 30, 40 and 50 days of treatment and the total number of adults emerged after 50 days. In this bioassay, wheat flour diet was treated separately with various concentrations (2.5%, 5% and 10%) of VPE and VME and insects were reared on it. Results revealed that there was significant reduction or inhibition of emergence of adults in treatments during different periods of exposure and also in the total number of adults emerged after 50 days compared to control. VPE at 10% concentration exhibited the highest per cent inhibition or lowest adult emergence index.