Efficacy of Beauveria bassiana against the red imported fire ant, Solenopsis invicta (Hymenoptera: Formicidae), in Taiwan.

BACKGROUND: Combining biological control and chemical control could be used for controlling red imported fire ant (RIFA), Solenopsis invicta, more effectively. Beauveria bassiana F256, a local strain from Taiwan, was evaluated for its efficacy in the control of S. invicta under both laboratory and field conditions.

RESULTS: The efficacies of different doses of B. bassiana (Bb) using direct application and bait formulation methods were compared. The number of RIFA workers killed by the direct application of Bb or by bait were significantly higher than those of the control, with different rates of efficacy under laboratory conditions. Under field conditions, the direct application of Bb into RIFA mounds was more efficient in inactivating the mounds than the bait application.

CONCLUSION: It was shown that B. bassiana is able to control S. invicta under both laboratory and field conditions and can be used as a biocontrol agent against RIFA in Taiwan.