Mortality, Stadial Duration, and Weight Loss in Three Species of Mass-reared Fruit Fly Pupae (Diptera: Tephritidae) Held with and without Vermiculite at Selected Relative Humidities

Abstract

Mediterranean fruit fly, Ceratitis capitata (Wiedemann); melon fly, Dacus cucurbitae Coquillett; and oriental fruit fly, Dacus dorsalis Hendel, pupae were held with and without a pupation medium (vermiculite) at 20°C and 90, 60, and 40% RH. For all three species of fruit flies, pupae held with vermiculite were significantly heavier than those held without vermiculite. Storage of pupae in boxes of vermiculite significantly reduced mortality at both 60 and 40% RH. For pupae held without vermiculite, lowest mortality, shortest stadial duration, and highest weight occurred at 90% RH for all three species. At 90% RH, mortality of pupae held without vermiculite did not differ significantly from mortality of those held with vermiculite. Results are discussed with respect to selection of holding procedures for mass-produced fruit fly pupae for programs involving the sterile insect release method.