MORTALITY OF FERAL CARIBBEAN FRUIT-FLY (DIPTERA, TEPHRITIDAE) IMMATURES IN COATED GUAVAS

Guavas from a commercial field near Homestead, FL, that were naturally infested with Caribbean fruit flies, Anastrepha suspensa (Loew), were coated with Nature Seal 2000, Nature Seal containing 4% hydroxypropyl cellulose, or Pac-Rite TFC 213 (a carnauba wax). Precoating infestati on rates ranged from 0 to 3.2 larvae per guava, and the mean Caribbean fruit fly survival in guavas coated with Nature Seal (4%), Nature Sea l 2000, or Pac-Rite TFC 213 was 9, 46, and 68%, respectively compared with uncoated controls.;Mean days to 50% emergence was 18.2 d for larv ae in guavas coated with Nature Seal (4%); this was significantly long er (95% CL) than the mean to 50% emergence for larvae in uncoated guav as (13.4 d) or those in guavas coated with Pac-Rite TFC 213 (13.2 d). Carbon dioxide levels were generally higher and oxygen levels generall y lower in Nature Seal-coated guavas compared with uncoated guavas. Co atings can lower Caribbean fruit fly survival rates in guavas and migh t become a component of a systems approach to allow export of guavas f rom Florida to of the world that require fruit fly treatment.