Evaluating behavioral avoidance and horizontal transmission of Beauveria bassiana in bed bugs (Cimex lectularius) across spatially complex environments

The resurgence of bed bugs (Cimex lectularius) since 1990’s has led to an increased dependence on chemical insecticides like pyrethroids and neonicotinoids for control. The use of such pesticides has further led to an evolved biological resistance among bed bug strains. As a result, the entomopathogenic fungus like Beauveria bassiana, in the form of commercial biopesticide Aprehend, is gaining attention as an alternative control measure. Laboratory studies confirm the efficacy and potential for horizontal transmission of Beauveria bassiana between bed bugs. However, we lack empirical studies that examine: (1) the extent to which bed bugs behaviorally avoid fungal spores; and (2) how spatially complex or cluttered environments affect fungal transmission in real-world situations. In this study, I conducted behavioral assays to understand if bed bugs avoid Aprehend-treated areas and if horizontal transmission decreases in spatially complex arenas and higher densities. My results showed no significant avoidance, as bed bugs chose treated and control zones at similar rates. Horizontal transmission was high across all spatially complex arenas and densities. However, survival results showed that while spatially complex arenas had no significant impact, density did affect the survival time of bed bugs exposed to Aprehend. Bed bugs in high density arenas survived longer, which could be due to some form of social protection. These findings shows that Aprehend is effective even in highly complex or cluttered environments and that density plays an important role in influencing survival time within bed bug colonies.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Entomology

Grantor

University of Illinois Urbana-Champaign

Year dc:date

2025

Author dc:creator

• Basnet, Vinisha Singh

Contributors dc:contributor

• Schneider, Daniel W.
• Schneider, Daniel W
• Allan, Brian F
• Stone, Christopher M.

• Entomopathogenic Fungus
• Aprehend
• Four-way Arena Choice
• Complex Environment.

Statement dc:rights

• Copyright 2025 Vinisha Basnet

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/130045

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F130045