Evaluation of Various Candidate Insecticides for Quarantine Treatments Against Imported Fire Ants, Solenopsis Invicta Buren, 1990

Abstract

Nine insecticides were evaluated at Gulfport, Miss., for quarantine treatments of nursery potting media capable of harboring imported fire ant (IFA) colonies. Treatments for this media are required to prevent accidental introduction of IFA into uninfested areas via shipment of commercial nursery stock. Candidate insecticides were incorporated into a commonly used potting media (Strong-lite, 382 lb/cu yd) at 11.35 g AI (theoretical dose rate ca. 65 ppm) in a 2 cu ft capacity electric cement mixer for 1 h to assure a uniform mix. Treated media were placed in trade 1 gal plastic pots and aged out of doors under ambient conditions. After 30 d exposure to natural rainfall and temperature (no irrigation added), 3 pots from each treatment were bioassayed by confining 5 field collected alate IFA queens (4 replicates) to 25 cc each of treated media for 7 d. Treatments that allowed any survival were considered ineffective. Subsequent bioassays of effective treatments were carried out at 30 d intervals.