House Fly (Diptera: Muscidae) Resting Preference on Various Cords and Potential of Fipronil- or Indoxacarb- Impregnation on Cords for Fly Control

Fly preference for resting on various cords was evaluated, and preferred cords were impregnated with insecticides for control of house flies, Musca domestica L. (Diptera: Muscidae). Numbers of house flies attracted to and resting on natural (manila, cotton, cotton wick, wool, and leather) and synthetic (nylon, polypropylene, and parachute cord) cords were counted. Synthetic cords attracted significantly fewer flies than natural cords, and the plant-based cords were more attractive than the animal-based cords. Manila cord had significantly more flies resting on it than any other cord. The most attractive cords were treated with 0.1% fipronil or 0.6% indoxacarb for laboratory testing. Insecticide-treated wool cord had the lowest LT50's (fipronil: LT50 = 12.9 h; indoxacarb LT50 = 32.6 h), and the impregnated cotton cord had the highest LT50's. The LT50's for the synthetic cords were significantly lower than those for the cotton and manila cords. Field evaluations in cages were conducted with wool cords impregnated with 0.1% fipronil or 1.2% indoxacarb. Both treatments significantly reduced fly counts at both 24 h and 48 h after placement, both initially and at 2-wk after treatment. Fipronil and indoxacarb both appear to be effective insecticides for house fly control, especially when they are applied to wool cords. With new active ingredients, insecticide-impregnated cords could be valuable tools in present-day urban, agriculture, and military fly management programs.