Surface Activity of Benzoylphenyl Urea Formulations, 1987

Tests were conducted to evaluate the relative efficacy of 3 formulated chitin synthesis inhibitors (benzoylphenyl ureas), triflumuron (25% W, alsystin), chlorfluazuron (25% W, CGA 112913) and UC 84572 (24.5% F), against nymphal stages of the German cockroach. Aqueous spray suspensions of various concentrations were applied to 4- x 4-inch (103 cm2) tempered masonite panels at a rate of 1 gal/1000 ft2 (0.42 ml/103 cm2) using a mechanized spray tower apparatus equipped with a stainless steel nozzle tip, Spraying Systems Teejet 8001E, at a constant pressure of 25 psi. Test insects were reared in 7- by 5- by 3½-inch (225.8 cm2) plastic boxes, lightly greased with a mixture of petrolatum and mineral and equipped with ventilated lids to prevent escape. Treated panels were introduced within 6 h of treatment and placed on the bottom at one end of the box with food and water positioned on top of the treated panel. A 20-inch2 cardboard tent, placed at the other end of the box, served as harborage. This design offered the test insects a choice of harborage areas, but assured exposure to the compounds during daily food and water consumption. Twenty late fourth stage nymphs were released into the confinement with the appropriate panel type; each treatment was replicated 4 times, for a total of 80 insects. The insects were maintained here until all had reached adulthood or died. Response variables evaluated in this study were insects dying during a molt event; insects surviving the molt to adulthood, but affected by exposure to the chitin inhibitor; and the combined mortality from molt inhibition and those adults dying within 1 wk of eclosion.