Chemical profiling and bioactivities of common commercial essential oils against larvae and adults of Tribolium castaneum: Insecticidal, behavioral, and biochemical effects

Commercial EOs offer standardized formulations ensuring consistent pest control. Hence, this study aims to assess the chemical profile, insecticidal (fumigant and contact toxicity), and behavioral activities (repellent and antifeedant) of four commonly commercial essential oils namely Artemisia herba alba, Eucalyptus globulus, Mentha pulegium, and Salvia rosmarinus against larvae and adults of Tribolium castaneum. This study also highlights the effect of effective EOs on activities of digestive (alpha-amylases), detoxification (alpha-carboxylesterase), and oxidative stress enzymes (catalase, peroxidase, superoxide dismutase). M. pulegium displayed the highest fumigant and contact toxicity against adults with respective LC50 values of 23.7 mu L/L of air, and 0.075 mu L/cm2 after 24 h. In the repellent bioassay, All EOs displayed strong repellency against adults with M. pulegium being the most active EO displaying 96 % of PR after 24 h at 0.031 mu L/cm2. In contrast, 92 and 76 % were the highest PR values demonstrated by A. herba and M. pulegium EOs, respectively, against larvae at 0.125 mu L/cm2 after 24 h. The antifeedant test showed that S. rosmarinus, A. herba alba, and M. pulegium exhibited the highest feeding deterrence (FDI) against adults with a respective FDI percentage of 67.7, 59.5 and 48 % at 0.64 mu L/pellet. On the other hand, Ingesting M. pulegium EO induced a 4-fold decrease in alpha-amylases activity, while a significant increase was observed in the antioxidant enzymes after fumigant, contact, and ingestion. The strong insecticidal, behavioral, and biochemical activities displayed by M. pulegium EO activities can be attributed to its major compound pulegone (46.49 %) detected using GC-MS. Our study highlights the potential of commercial M. pulegium as a potent insecticidal, repellent, feeding deterrent for the management of T. castaneum.