Gamma Radiation as a Quarantine Treatment for Hawaiian Fruit Flies1

Abstract

Gamma rays from a cobalt-60 source were applied to egg and larval infestations of the oriental fruit fly, Dacus dorsalis Hendel; melon fly, D. cucurbitae Coquillet; and Mediterranean fruit fly, Ceratitis capitata (Wiedemann), in various fruits and vegetables to investigate such radiation as a quarantine treatment for fresh commodities. A dosage of 10 kr generally prevented immature stages of fruit flies from developing to adults. Dosages over 100 kr failed to prevent pupation. Mortalities were converted to probits, and LD99.0 and LD99.9968 determined for the oriental fruit fly and the melon fly. Solo papayas, tomatoes, cucumbers, bananas, litchis, and ripe mangoes tolerated dosages between 25 kr and 100 kr without losing commercial acceptability. Most varieties of avocados and mature-green Haden mangoes were injured by 25 kr.