Document Type
Article
Publication Date
2023
Keywords
Lone star tick, entomopathogenic fungi, mycoinsecticide, al- ternative tick control
Abstract
The lone star tick, Amblyomma americanum, is the predominant human-biting tick in Arkansas and a vector of multiple pathogens of medical and veterinary importance. Increasing concerns over acaricide resistance and environmental contamination have prompted evaluation of alternative control strategies. We assessed the pathogenicity of a native Arkansas isolate of Metarhizium robertsii (Savoy P10N1) against laboratory-reared adult and nymphal A. americanum under controlled conditions. Ticks were immersed in a conidial suspension (1 × 10⁸ conidia/ml) and monitored for mortality and fungal sporulation for 77 days post-inoculation. Cumulative mortality followed a time-dependent logistic pattern, with significant fungal-induced mortality beginning at 14 days post-inoculation. By day 77, 25% of adults and 26% of nymphs had died, and 72–82% of dead ticks exhibited visible mycosis. Control mortality was negligible (< 1%). Although overall mortality was moderate and occurred gradually, nearly all dead ticks showed evidence of fungal infection, confirming pathogenicity of this native isolate. These results represent the first laboratory evaluation of an unformulated, southern U.S. isolate of M. robertsii against A. americanum and suggest potential for integration of native entomopathogenic fungi into long-term tick management programs.
Citation
Goldsmith, Austin T., Kelly Loftin, Donald Steinkraus, Allen Szalanski, and Blair J. Sampson. "Laboratory Bioassays of a Native Arkansas Isolate of Metarhizium robertsii (Hypocreales: Clavicipitaceae) for the Control of Amblyomma americanum (Acarina: Ixodidae)." Journal of Agricultural and Urban Entomology 39, no. 1 (2023): 21-27.
