The interaction between strain and food type influences biological parameters of Tribolium castaneum and its susceptibility to Dennettia tripetala extract

Abstract

AbstractThe red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), is a cosmopolitan insect pest that infests a wide range of milled cereal flours. In this study, the main and interactive effects of geographic origin and food type on the biological response of T. castaneum, and its susceptibility to the fumigant toxicity of sub‐lethal concentrations of Dennettia tripetala (G Baker) (Annonaceae) extract were investigated. The Nigeria and America (USA) strains of T. castaneum, used in this study, were maintained on corn (= maize) and wheat flours for four generations. This study was done under ambient laboratory conditions (23–35 °C and 65–85% r.h.). Irrespective of the food type, the larval, pupal, and adult stages were generally bigger in the America strain than in the Nigeria strain. The interaction of strain with food significantly affected the larval weight of T. castaneum. The larval periods and total developmental periods were significantly higher in both strains reared on corn than on wheat flour. However, only the food type significantly affected the pupal developmental periods. The insecticide susceptibility of larvae and adults of T. castaneum to D. tripetala extract was significantly higher in the strain from America than in the strain from Nigeria. Also, there were significant effects of food type and experimental concentration on the response of larvae and adults to D. tripetala extract. The extract was more toxic to adults than to larvae. Various results obtained in this study could provide data that are needed for the development of accurate phenology models for T. castaneum in Nigeria. Our study also underscores the significance of geographical strain and food type when managing T. castaneum with a plant‐based insecticide.