|Briano, Juan - USDA-ARS ARGENTINA|
Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 1, 2000
Publication Date: N/A
Interpretive Summary: Matching biotypes of potential biocontrol agents to target host populations can greatly improve the effectiveness of control. An ARS scientist at the Center for Medical, Agricultural and Veterinary Entomology (CMAVE) in Gainesville, FL and his colleague at the ARS South American Biological Control Laboratory (SABCL) in Hurlingham, Argentina tested the hypothesis that the decapitating fly Pseudacteon curvatus from Las Flores, Buenos Aires Province, Argentina would prefer its natural host, the black fire ant, over the closely related red fire ant. They found that this fly strongly preferred black fire ants from Argentina, black fire ants from the United States, and hybrid (red x black) fire ants from the United States when each was tested against red imported fire ants from the United States. These results suggest that this species of decapitating fly may do best if released as a biocontrol agent against black or hybrid imported fire ants. Nevertheless, parasitism rates were not significantly different among thes ant hosts in no-choice parasitism tests; thus suggesting that this fly may still be an effective biocontrol agent against black, red, and hybrid imported fire ants in the United States.
Technical Abstract: Matching biotypes of potential biocontrol agents to target host populations can greatly improve the effectiveness of control. This study was designed to determine if the fly Pseudacteon curvatus Borgmeier from Las Flores, Buenos Aires Province, Argentina prefers its natural host, the black fire ant, Solenopsis richteri Forel. We found that P. curvatus strongly preferred S. richteri from Argentina, imported S. richteri from the United States, and hybrid (S. richteri x S. invicta) fire ants from the United States when each was tested against S. invicta from the United States. The time to pupation of developing parasitoids was 10 percent and 21 percent longer in hybrid and red fire ants than in black fire ants. Parasitism rates, however, were not significantly different among these ant hosts in no-choice parasitism tests.