Abstract:
Laboratory experiments were conducted at the College of Agricultural Studies, Sudan University of Science and Technology, to evaluate the insecticidal effect of korobi Nerium oleander L, Damas Conocarpus lancifolius Engl and Mahogany Khaya senegalensis (Desr. A.Juss). against red flour beetle Tribolium castaneum Herbst.
Three formulations (powder, aqueous and ethanolic extract of each plant were used under three concentrations . Three concentrations from each plant (5%, 10% and 15%) were used in this study. The results showed that all concentrations of all tested plants in various formulations gave significantly higher mortality percentage than the control after 24hrs of exposure.
The highest concentration (15%) of Nerium leaves powder revealed only 38.4% mortality after 72 hrs of exposure, whereas, the same concentration of Nerium leaves aqueous and ethanolic extracts gave higher mortality percentage (48.4%). Meanwhile, the highest concentration of Damas leaves aqueous extract generated only 38.4% mortality after 72 hrs of exposure, whereas, the same concentration of Damas leaves ethanolic extract caused 41.7% mortality.
The obtained results also revealed that the highest concentration of Mahogany leaves powder, aqueous extract and ethanolic extract induced 25%, 31.7% and 55% mortality respectively after 72 hrs of application.
