TY - JOUR

T1 - Common facultative endosymbionts do not influence sensitivity of cereal aphids to pyrethroids

AU - Leybourne, Daniel J.

AU - Melloh, Petra

AU - Martin, Emily A.

N1 - Funding Information: This project was supported by the Alexander von Humboldt Foundation through a Postdoctoral Research Fellowship to DJL. The authors thank Alexander Manentzos, Anna‐Lena Heitkamp, Kristina Dauven, Eric Mühlnikel, Christoph Harms and Antonia Pahl for assisting with aphid sampling. The authors thank S Donner and M Beekman (Wageningen University & Research, The Netherlands) for providing positive endosymbiont DNA samples. Open Access funding enabled and organized by Projekt DEAL.

PY - 2023/4/3

Y1 - 2023/4/3

N2 - Cereal aphids, including the bird cherry-oat aphid, Rhopalosiphum padi, and the grain aphid, Sitobion avenae, can transmit viruses that significantly reduce crop yields. To mitigate against yield losses, insecticides are routinely used to manage aphid populations. Aphids can form relationships with endosymbionts that confer fitness benefits or consequences to the aphid. Recent artificial inoculation experiments indicate that endosymbionts could increase aphid susceptibility to insecticides, but this has not been explored using aphid populations naturally infected with endosymbionts. Here, we sampled aphids from an important cereal production region in Lower Saxony, Germany. We characterized the endosymbiont profile of these aphid populations and conducted pyrethroid dose–response assays to test the hypothesis that facultative endosymbionts increase aphid susceptibility to insecticides. We find that the level of insecticide susceptibility is highly variable in S. avenae and we identify populations that are sensitive and tolerant to pyrethroids, including populations collected from the same field. For R. padi, we find evidence for decreased sensitivity to pyrethroids, representing the first report of reduced sensitivity to pyrethroids in R. padi sampled from Central Europe. We detected high endosymbiont infection frequencies in the aphid populations. 84% of aphids carry one facultative endosymbiont and 9% of aphids carry two facultative endosymbionts. We detected associations with Regiella insecticola, Fukatsia symbiotica, and Hamiltonella defensa. However, we do not identify a link between endosymbiont infection and insecticide susceptibility, indicating that other factors may govern the development of insecticide resistance and the need for alternative management strategies.

AB - Cereal aphids, including the bird cherry-oat aphid, Rhopalosiphum padi, and the grain aphid, Sitobion avenae, can transmit viruses that significantly reduce crop yields. To mitigate against yield losses, insecticides are routinely used to manage aphid populations. Aphids can form relationships with endosymbionts that confer fitness benefits or consequences to the aphid. Recent artificial inoculation experiments indicate that endosymbionts could increase aphid susceptibility to insecticides, but this has not been explored using aphid populations naturally infected with endosymbionts. Here, we sampled aphids from an important cereal production region in Lower Saxony, Germany. We characterized the endosymbiont profile of these aphid populations and conducted pyrethroid dose–response assays to test the hypothesis that facultative endosymbionts increase aphid susceptibility to insecticides. We find that the level of insecticide susceptibility is highly variable in S. avenae and we identify populations that are sensitive and tolerant to pyrethroids, including populations collected from the same field. For R. padi, we find evidence for decreased sensitivity to pyrethroids, representing the first report of reduced sensitivity to pyrethroids in R. padi sampled from Central Europe. We detected high endosymbiont infection frequencies in the aphid populations. 84% of aphids carry one facultative endosymbiont and 9% of aphids carry two facultative endosymbionts. We detected associations with Regiella insecticola, Fukatsia symbiotica, and Hamiltonella defensa. However, we do not identify a link between endosymbiont infection and insecticide susceptibility, indicating that other factors may govern the development of insecticide resistance and the need for alternative management strategies.

KW - Dose response

KW - Endosymbionts

KW - Insecticide tolerance

KW - Pest management

KW - Pyrethroid

UR - http://www.scopus.com/inward/record.url?scp=85138627280&partnerID=8YFLogxK

U2 - 10.1101/2022.05.24.493255

DO - 10.1101/2022.05.24.493255

M3 - Short/Brief/Rapid Communication

AN - SCOPUS:85138627280

VL - 25

SP - 344

EP - 354

JO - Agricultural and Forest Entomology

JF - Agricultural and Forest Entomology

SN - 1461-9555

IS - 2

ER -