Fumigant toxicity of essential oils from Citrus reticulata Blanco fruit peels against Tribolium castaneum Herbst (Coleoptera: Tenebrionidae)

Certain compounds of plants such as essential oils, with insecticidal properties have been considered as alternatives to chemical pesticides for pest control. This study reports the fumigant toxicity of Citrus reticulata Blanco (Rutaceae) peel essential oils against stored-product insect pest, red flour beetle, Tribolium castaneum Herbst (Tenebrionidae) adults. Experiment was carried out at ۲۷ ± ۱ °C and ۶۰ ± ۵ % relative humidity in darkness. Experimental concentrations were ۱۵, ۲۲, ۳۱, ۴۵, and ۶۳ μl/l air tested on adult (۱-۷ days old) insects after ۲۴ and ۴۸ h of exposure. Results indicated that essential oils from C. reticulata had fumigant tocxicity effects against this stored pest. LC۵۰ values were ۳۸.۲ and ۳۵.۶ μl/l air at ۲۴ and ۴۸ h after exposure of T. castaneum adults respectively. The essential oils of Citrus reticulata fruit peels at the highest dose of ۶۳ μl/l air caused ۷۶.۶ % and ۷۹ % mortality of insects after ۲۴ and ۴۸ hours of exposure, respectively. Mortality of T. castaneum increased with both increase in concentration of C. reticulata oils as well as exposure time of treated insects. These results suggest the potencial of C. reticulata oil as a control agent against T. castaneum.

Keywords:

Citrus reticulata , Essential oil , toxicity , Tribolium castaneum