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bioRxiv · 10.1101/2020.01.11.901751

Imidacloprid Movement into Fungal Conidia is Lethal to Mycophagous Beetles

Choudhury, R. A.·Sutherland, A. M.·Hengel, M. J.·Parrella, M. P.·Gubler, W. D.
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Abstract

O_LIApplications of systemic pesticides can have unexpected direct and indirect effects on nontarget organisms, producing ecosystem-level impacts. C_LIO_LIWe investigated whether a systemic insecticide (imidacloprid) could be absorbed by a plant pathogenic fungus infecting treated plants and whether the absorbed levels were high enough to have detrimental effects on the survival of a mycophagous beetle. Beetle larvae fed on these fungi were used to assess the survival effects of powdery mildew and imidacloprid in a factorial design. Fungal conidia were collected from treated and untreated plants and were tested for the presence and concentration of imidacloprid. C_LIO_LISurvival of beetles fed powdery mildew from imidacloprid-treated leaves was significantly lower than that of beetles from all other treatments. C_LIO_LIImidacloprid accumulated in fungal conidia and hyphae was detected at levels considered lethal to other insects, including coccinellid beetles. C_LIO_LIWater-soluble systemic insecticides may disrupt mycophagous insects as well as other nontarget organisms, with significant implications for biodiversity and ecosystem function. C_LI

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Choudhury, R. A., Sutherland, A. M., Hengel, M. J., Parrella, M. P., Gubler, W. D.. 2020-01-11. Imidacloprid Movement into Fungal Conidia is Lethal to Mycophagous Beetles. https://doi.org/10.1101/2020.01.11.901751

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