CONTROLLED-RELEASE PANEL TRAPS FOR THE MEDITERRANEAN FRUIT-FLY (DIPTERA, TEPHRITIDAE)

Solid, controlled-release dispensers containing 2 g of the synthetic a ttractant trimedlure now are used in Jackson traps to detect the Medit erranean fruit fly, Ceratitis capitata (Wiedemann). Panel traps consis ting of trimedlure mixed in a sticky substance and spread on the surfa ces of a plastic panel are used to delineate the limits of discovered insect infestations in California. We describe the development of cont rolled-release, polymeric panels that prolong release of trimedlure an d a highly attractive analog, ceralure. Attractants were incorporated in a polyethylene matrix to form panels and in a polymer coating on ca rdboard panels that then were evaluated by biological and chemical ass ay. In addition, commercial polymer matrix panels were evaluated. Fiel d bioassay tests conducted in Hilo, HI, using released flies and in Gu atemala in a natural population showed that the polyethylene matrix pa nel became brittle and cracked during field exposure and that release rates of the attractants were relatively low. The coated cardboard pan els were stable under field conditions and yielded high fly captures f or up to 6 wk. Farma Tech commercial panels containing 12.3 and 23.4 g of trimedlure remained highly attractive throughout a 134-d test in H awaii and appear to be a long-lasting alternative to panels coated wit h trimedlure in Stikem. The cost of the relatively high dose of trimed lure is offset by the prolonged active life of the panel. Commercial p anels from AgriSense (10 g trimedlure and 10 g ceralure) released the attractants at a slower rate and were less attractive.