Possible Antagonistic Activity of Two Entomopathogens Infecting Workers of the Red Imported Fire Ant (Hymenoptera: Formicidae)

Densities of the red imported fire ant, Solenopsis invicta (Buren), within its range in the United States are 4x to 7x greater than in its native range in South America (Porter, S.D. et al., Environ.Entomol.26:373-384, 1997).This is primarily due to a lack of natural enemies in its expanded range in North America (Porter et al. 1997; Jouvenaz, D.P., Florida Entomol.66:111-121, 1983).Several natural enemies have been studied as to their potential for controlling fire ants in the southern United States.These include the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Pereira, R.