|WANG, LEI - South China Agricultural University|
|ZENG, LI - South China Agricultural University|
Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/9/2015
Publication Date: 12/8/2015
Publication URL: http://handle.nal.usda.gov/10113/61871
Citation: Wang, L., Zeng, L., Chen, J. 2015. Impact of imidacloprid on new queens of imported fire ants, Solenopsis invicta (Hymenoptera: Formicidae). Scientific Reports. 5:Aricle number:17938 doi:10.1038/srep17938.
Interpretive Summary: Red imported fire ants are a significant pest. Annual economic cost associated with imported fire ant in the USA alone has reached 5.6 billion dollars. Neonicotinoid insecticides are commonly used in managing the imported fire ants. It is known that neonicotinoid insecticides affect behavior and survival of some social insects at very low doses. However, the effect of neonicotinoid insecticides on the red imported fire ants has never been investigated at low doses. In this study, the newly mated queens were fed with water containing imidacloprid, a common neonicotinoid insecticide. Although imidacloprid did not increase the mortality of queens, it significantly affected their behavior and the development of the incipient colonies. The results from this study may help us develop new approaches for more effective utilization of neonicotinoid pesticides in fire ant management. On the other hand, the results can also serve as an alert for the potential detrimental impact of neonicotinoid insecticide residuals on the beneficial ants.
Technical Abstract: Neonicotinoid insecticides are commonly used in managing pest ants, including the imported fire ant, Solenopsis invicta Buren. There is increasing evidence that neonicotinoid insecticides at sublethal concentrations have profound effects on social insects. However, the sublethal effect of neonicotinoids on S. invicta has never been investigated. In this study, the newly mated queens were fed with water containing 0.01 or 0.25 µg/ml imidacloprid. Imidacloprid at both concentrations did not cause any increase in queen mortality during the founding stage; however, it significantly reduced queens’ brood tending ability. In the 0.25 µg/ml imidacloprid treatment, the time to larval emergence was significantly delayed and no pupae or adult workers were produced. This study provides clear evidence that imidacloprid at sublethal concentrations has a significant detrimental impact on S. invicta queens and the development of incipient colonies.