Spillage and food dust do not decrease efficacy of long-lasting insecticide-incorporated netting against stored product insects

Authors: RANABHAT, SABITA - Kansas State University; MUTLU, CETIN - Harran University; BINGHAM, GEORGINA - University Of Nebraska; Abshire, Jennifer; MCKAY, TANJA - Arkansas State University; ZHU, KUN YAN - Kansas State University; Morrison Iii, William

Submitted to: Journal of Stored Products Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/15/2025
Publication Date: 4/19/2025
Citation: Ranabhat, S., Mutlu, C., Bingham, G.V., Abshire, J.L., Mckay, T., Zhu, K., Morrison Iii, W.R. 2025. Spillage and food dust do not decrease efficacy of long-lasting insecticide-incorporated netting against stored product insects. Journal of Stored Products Research. https://doi.org/10.1016/j.jspr.2025.102662.
DOI: https://doi.org/10.1016/j.jspr.2025.102662

Interpretive Summary: Flour mills and food facilities produce substantial amounts of dust, debris, and particles (spillage) that can serve as food sources for stored product insects. Sanitation, or the removal of spillage, is a key component in stored product pest management; however, it is not always possible to completely eliminate debris due to the effort, time, and cost required to keep a facility clean. Long-lasting insecticide-incorporated netting can be successfully used to control stored product insects; however, it is not known how food dust may alter its efficacy against common stored product insects, such as red flour beetle and lesser grain borer. We observed similar mortality for both insects when insecticide nets were dipped in flour compared to undipped nets and when insecticide netting was placed over spilled flour, indicating that spillage did not impact efficacy. Interestingly, we found that the netting reduced movement of lesser grain borer when it was placed over a site of spillage, suggesting that netting could be placed in areas of high spillage to reduce some stored product pest populations. Overall, these results suggest that food dust will minimally affect insecticide net efficacy against stored product insects.

Technical Abstract: The foundation of many integrated pest management (IPM) programs after harvest is proper sanitation. However, there may be deviations from this as a result of the effort, time, and cost required to keep a facility clean. Long-lasting insecticide-incorporated netting (LLIN) has been used successfully to augment IPM programs after harvest, but has not yet been investigated for its role in supporting sanitation. Here, we investigated the use of LLIN to spot treat spillage and how food dust deposition may alter efficacy against Tribolium castaneum and Rhyzopertha dominica. After immersing alpha-cypermethrin LLINs in flour, we found no significant changes in adults classified as alive, affected, and dead compared to undipped LLINs. We found slightly more recovery by T. castaneum after exposure to deltamethrin LLIN in the presence of food dust compared to when it was absent. When a layer of LLIN was used to cover spillage, we found statistically equivalent numbers of affected and dead individuals induced compared to when spillage was absent. After holding spillage for 6 weeks, no larvae and 87% fewer pupae were produced by T. castaneum after exposure to a layer of alpha-cypermethrin LLIN for 48 h, compared to netting without insecticide. Finally, we found a 2.5 cm strip of LLIN sufficiently impeded the dispersal of R. dominica on a site of spillage, but this was not the case for T. castaneum. Overall, these results suggest the use pattern for LLIN could be expanded, and that food dust will minimally affect LLIN efficacy against stored product insects.