Comparative Efficacy of a Fungal Entomopathogen with a Broad Host Range against Two Human-Associated Pests

The ability of a fungal entomopathogen to infect an insect depends on a variety of factors, including strain, host, and environmental conditions. Similarly, an insect’s ability to prevent fungal infection is dependent on its biology, environment, and evolutionary history. Synanthropic pests have ada...

Full description

Bibliographic Details
Main Authors: Aaron R. Ashbrook, Aram Mikaelyan, Coby Schal
Format: Article
Language:English
Published: MDPI AG 2022-08-01
Series:Insects
Subjects:
Online Access:https://www.mdpi.com/2075-4450/13/9/774
_version_ 1797486833590861824
author Aaron R. Ashbrook
Aram Mikaelyan
Coby Schal
author_facet Aaron R. Ashbrook
Aram Mikaelyan
Coby Schal
author_sort Aaron R. Ashbrook
collection DOAJ
description The ability of a fungal entomopathogen to infect an insect depends on a variety of factors, including strain, host, and environmental conditions. Similarly, an insect’s ability to prevent fungal infection is dependent on its biology, environment, and evolutionary history. Synanthropic pests have adapted to thrive in the indoor environment, yet they arose from divergent evolutionary lineages and occupy different feeding guilds. The hematophagous bed bug (<i>Cimex lectularius</i>) and omnivorous German cockroach (<i>Blattella germanica</i>) are highly successful indoors, but have evolved different physiological and behavioral adaptations to cope with the human-built environment, some of which also reduce the efficacy of fungal biopesticides. In order to gain greater insight into the host barriers that prevent or constrain fungal infection in bed bugs and German cockroaches, we tested different doses of <i>Beauveria bassiana</i> GHA through surface contact, topical application, feeding, and injection. Bed bugs were generally more susceptible to infection by <i>B</i>. <i>bassiana</i> with the mode of delivery having a significant impact on infectivity. The German cockroach was highly resilient to infection, requiring high doses of fungal conidia (>8.8 × 10<sup>4</sup>) delivered by injection into the hemocoel to cause mortality. Mortality occurred much faster in both insect species after exposure to surfaces dusted with dry conidia than surfaces treated with conidia suspended in water or oil. These findings highlight the importance of developing innovative delivery techniques to enhance fungal entomopathogens against bed bugs and cockroaches.
first_indexed 2024-03-09T23:39:46Z
format Article
id doaj.art-3dc00201a39b47289e85990341046e81
institution Directory Open Access Journal
issn 2075-4450
language English
last_indexed 2024-03-09T23:39:46Z
publishDate 2022-08-01
publisher MDPI AG
record_format Article
series Insects
spelling doaj.art-3dc00201a39b47289e85990341046e812023-11-23T16:54:30ZengMDPI AGInsects2075-44502022-08-0113977410.3390/insects13090774Comparative Efficacy of a Fungal Entomopathogen with a Broad Host Range against Two Human-Associated PestsAaron R. Ashbrook0Aram Mikaelyan1Coby Schal2Department of Entomology and Plant Pathology, North Carolina State University, 100 Derieux Place, Raleigh, NC 27695, USADepartment of Entomology and Plant Pathology, North Carolina State University, 100 Derieux Place, Raleigh, NC 27695, USADepartment of Entomology and Plant Pathology, North Carolina State University, 100 Derieux Place, Raleigh, NC 27695, USAThe ability of a fungal entomopathogen to infect an insect depends on a variety of factors, including strain, host, and environmental conditions. Similarly, an insect’s ability to prevent fungal infection is dependent on its biology, environment, and evolutionary history. Synanthropic pests have adapted to thrive in the indoor environment, yet they arose from divergent evolutionary lineages and occupy different feeding guilds. The hematophagous bed bug (<i>Cimex lectularius</i>) and omnivorous German cockroach (<i>Blattella germanica</i>) are highly successful indoors, but have evolved different physiological and behavioral adaptations to cope with the human-built environment, some of which also reduce the efficacy of fungal biopesticides. In order to gain greater insight into the host barriers that prevent or constrain fungal infection in bed bugs and German cockroaches, we tested different doses of <i>Beauveria bassiana</i> GHA through surface contact, topical application, feeding, and injection. Bed bugs were generally more susceptible to infection by <i>B</i>. <i>bassiana</i> with the mode of delivery having a significant impact on infectivity. The German cockroach was highly resilient to infection, requiring high doses of fungal conidia (>8.8 × 10<sup>4</sup>) delivered by injection into the hemocoel to cause mortality. Mortality occurred much faster in both insect species after exposure to surfaces dusted with dry conidia than surfaces treated with conidia suspended in water or oil. These findings highlight the importance of developing innovative delivery techniques to enhance fungal entomopathogens against bed bugs and cockroaches.https://www.mdpi.com/2075-4450/13/9/774bed bugsGerman cockroaches<i>Beauveria bassiana</i>entomopathogensbioassays
spellingShingle Aaron R. Ashbrook
Aram Mikaelyan
Coby Schal
Comparative Efficacy of a Fungal Entomopathogen with a Broad Host Range against Two Human-Associated Pests
Insects
bed bugs
German cockroaches
<i>Beauveria bassiana</i>
entomopathogens
bioassays
title Comparative Efficacy of a Fungal Entomopathogen with a Broad Host Range against Two Human-Associated Pests
title_full Comparative Efficacy of a Fungal Entomopathogen with a Broad Host Range against Two Human-Associated Pests
title_fullStr Comparative Efficacy of a Fungal Entomopathogen with a Broad Host Range against Two Human-Associated Pests
title_full_unstemmed Comparative Efficacy of a Fungal Entomopathogen with a Broad Host Range against Two Human-Associated Pests
title_short Comparative Efficacy of a Fungal Entomopathogen with a Broad Host Range against Two Human-Associated Pests
title_sort comparative efficacy of a fungal entomopathogen with a broad host range against two human associated pests
topic bed bugs
German cockroaches
<i>Beauveria bassiana</i>
entomopathogens
bioassays
url https://www.mdpi.com/2075-4450/13/9/774
work_keys_str_mv AT aaronrashbrook comparativeefficacyofafungalentomopathogenwithabroadhostrangeagainsttwohumanassociatedpests
AT arammikaelyan comparativeefficacyofafungalentomopathogenwithabroadhostrangeagainsttwohumanassociatedpests
AT cobyschal comparativeefficacyofafungalentomopathogenwithabroadhostrangeagainsttwohumanassociatedpests