Background: The current study was conducted in the Laboratory of Department of Crop Protection, Modibbo Adama University of Technology, Yola to evaluate the repellent effects of different concentrations of extracts of Azadirachta indica (Neem, Moringa oleifera (Drum stick) and Hyptis souveolens (Pig weed) against Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) at various time intervals and their interactions. Three concentrations viz; 5, 10 and 15% were applied to evaluate the Repellence of T. castaneum at five different exposure periods of 24, 48, 72, 96 and 120 hours. Repellence action of extracts of A. indica, H. souveolens and M. oleifera evaluated against the T. castaneum had maximum repellency (81.63%) at highest concentration of 15%, followed by H. souveolens (79.37%) and M. oleifera (50.46%). Regarding interaction between concentration and time, repellence increases with respect to increase in concentration, but reduces with passage of time. This shows that toxicity effects of these plant extracts is directly affected by concentration and time. Therefore, this study confirmed that these plant extracts are effective in the management of T. castaneum and most effectively at higher concentration within short period of time.
Toxic and Repellent Characteristics of Some Plant Extracts used against Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) Improve the Grain Quality of Stored Wheat