Submitted to: Midsouth Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/1/2008
Publication Date: 3/1/2008
Citation: Menzel, T.O., Cross, D.C., Chen, J., Caprio, M., Nebeker, T.E. 2008. A survey of Imported Fire Ant (Hymenoptera: Formicidae), species and social forms across four counties in east-central Mississippi. Midsouth Entomologist. 1:3-10. Interpretive Summary: Imported fire ants including red imported fire ants, black imported fire ants and their hybrid are all important agricultural and medical pest insects. We found that all the colonies collected from four counties in Mississippi were hybrid imported fire ants. We also found the first multiple queen hybrid colony. The results are useful as a guide for managing fire ants in these areas.
Technical Abstract: Molecular technology allows researchers to definitively identify red imported fire ants as either monoygyne or polygyne based on the alleles present at the Gp-9 locus. This technique has not previously been applied to hybrid individuals of the red imported fire ant and the black imported fire ant. Specimens were collected from 81 imported fire ant colonies from 27 locations over a four county area within the imported fire ant hybrid zone in east-central Mississippi. Gas chromatograph analysis of cuticular hydrocarbons and venom alkaloids was used to determine the species or species hybrid status of those colonies. Polymerase chain reaction (PCR) was used to determine the alleles present at the Gp-9 locus. All colonies were determined to be hybrid imported fire ants, and 14 colonies from seven locations possessed the Gp-9b allele, which is associated with polygyny. A colony possessing the Gp-9b allele was later found to have two queens, making it the first reported hybrid colony possessing the Gp-9b allele and expressing the polygyne phenotype.