Assessment of Corn Pollen as a Food Source for Two Tephritid Fruit Fly Species

Abstract

The melon fly, Bactrocera cucurbitae (Coquillett) is a serious pest of cucurbit crops. Although melon fly females oviposit in cucurbit crops, both males and females are frequently associated with a range of nonhost plants, including both crops such as corn (Zea mays C. Linnaeus) and wild plants such as castor bean (Ricinus communis C. Linnaeus) that occur within the cropping area or along the crop borders. This association with nonhost plants has been used for control purposes through the technique of spraying protein baits incorporating a toxicant on these nonhost plants. Association of melon flies to corn has not been reported to be tied to any phenological stage of corn. We report field studies that show that melon flies, as well as oriental fruit flies, B. dorsalis (Hendel), may show increased population levels in corn at the time of, and subsequent to, flowering and pollen shed and suggest that this population increase may be tied to pollen consumption. Before this, pollen had not been reported to be an important food source for the tropical Bactrocera spp.