Unleashing the power of diatomaceous earths for sustainable management of Tribolium castaneum infestation in wheat

The utilization of diatomaceous earths (DEs) has been considered as a potential alternative to traditional in-secticides for controlling grain storage insect pests. In this study, 19 different commercial DEs obtained from various regions of the world were evaluated for their effectiveness to manage Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), in vitro. Two different series of bioassays were carried out, with the first screening all 19 DEs and the second evaluating the eight most effective ones at different doses and exposure intervals for mortality assessment and progeny production. Four enhanced DEs, namely InertPMS, DEA, DiaHerb, and DEBBM were highly effective compared to other DEs tested. InertPMS exhibited complete adult mortality at 50 mg/kg, followed by DEA at 75 mg/kg, DiaHerb at 100 mg/kg, and DEBBM at 125 mg/kg, while GrainGuard exhibited 94.52 % at 125 mg/kg, 14 days post-exposure. Protect-It, SilicoSec, and DiaFil 610 were less effective at 400 mg/ kg, causing 87.3 %, 84.4 %, and 79.2 % mortality after 14 days, respectively. The offspring was suppressed in wheat treated with InertPMS at 75 mg/kg, while DEA, DiaHerb, and DEBBM revealed no progeny emergence at 125 mg/kg. GrainGuard, Protect-It, SilicoSec, and DiaFil 610 were not successful at progeny suspension after 62 days. These findings suggest that the use of specific DEs at low doses could be a viable option to mitigate the use of conventional insecticides and diminish the residues of insecticides on stored grains, making them the most feasible components for integrated pest management (IPM) in stored grain systems.

Automated summary

This study evaluated the effectiveness of 19 different commercial diatomaceous earths (DEs) in controlling Tribolium castaneum in vitro. Four enhanced DEs were found to be highly effective compared to other DEs tested. These findings suggest that the use of specific DEs at low doses could be a viable option for integrated pest management in stored grain systems.