Thermal Death of Oriental Fruit Fly (Diptera: Tephritidae) Third Instars in Developing Quarantine Treatments for Papayas

Current quarantine treatments to disinfest papayas of fruit flies (Diptera: Tephritidae) are often either detrimental to fruit quality or restricted to fruit less than one-quarter ripe. After phytotoxicity limits were established, thermal death studies were done on third-instar oriental fruit fly, Dacus dorsalis Hendel, in artificially infested papayas. A hot-water immersion and two low-humidity, hot-air treatments were examined. Mature green to half-ripe papayas heated in 45.6°C. A two-term polynomial expression described the increase in measured fruit center temperatures with heating times at low humidity. Center temperatures of different size fruits reached the same level if heated >4 h.