Dacus cucurbitae Pumpkin Fruit fly

1. DacuscucurbitaePumpkin Fruit fly

2. CLASSIFICATION • Kingdom:Animalia • Phylum:Arthropoda • Class:Insecta • Order:Diptera • Section:Schizophora • Family:Tephritidae • Genus:Bactrocera • Species:B. curcurbitae

3. ADULT • The adult melon fly is 6 to 8 mm in length. Distinctive characteristics include its wing pattern, its long third antennal segment, the reddish yellow dorsum of the thorax with light yellow markings, and the yellowish head with black spots.

4. EGG • The egg is elliptical, about 2 mm long, and pure white. It is almost flat on the ventral surface, and more convex on the dorsal. Eggs are often somewhat longitudinally curved.

5. LARVA • The larva is a cylindrical-maggot shape, elongated, with the anterior end narrowed a somewhat curved ventrally. It has anterior mouth hooks, ventral fusiform areas and a flattened caudal end. Last instar larvae range from 7.5 to 11.8 mm in length. The venter has fusiform areas on segments 2 through 11. The anterior buccalcarinae are usually 18 to 20 in number. The anterior spiracles are slightly convex in lateral view, with relatively small tubules averaging 18 to 20 in number

6. PUPA • The puparium ranges in color from dull red or brownish yellow to dull white, and is about 5 to 6 mm in length.

7. LIFE CYCLE • Development period from egg to adult ranges from 12 to 28 days. The female may lay as many as 1,000 eggs. Eggs are generally laid in young fruit, but are also laid in the succulent stems ofhost plants. The eggs are deposited in cavities created by the female using its sharp ovipositor. • Pupation usually occurs in the soil. There may be as many as 8 to 10 generations a year.

8. DAMAGE • In the Indo-Malayan region, the melon fly is considered the most destructive pest of melons and other related crops. In Hawaii, it has caused serious damaged to melon, cucumber and tomato crops. • The melon fly can attack flowers, stem, roottissue, and fruit.

9. MANAGEMENT • Non-chemical control • Mechanical • The two most common mechanical methods of control are wrapping developing fruit with a protective covering and the use of baited traps. • Cultural • The most effective cultural management technique is the destruction of all infested and unmarketable fruit, and the disposal of crop residues immediately after harvest. • Biological control • A technician prepares to irradiate male melon fly pupae to sterilize them • Between 1947 and 1952, thirty-two species and varieties of natural enemies to fruit flies were introduced in Hawaii. These parasites lay their eggs in the eggs ormaggots and emerge in the pupal stage. • When the parasitoidsF. arisanus or P. fletcheri were used, and attacked both melon fly eggs and larvae at the same time, suppression of development was as much as 56%

10. Irradiation • Sterilization of male melon flies through irradiation has proven effective in significantly reducing the number of eggs hatching. • Chemical control • Toxicants in baits applied both to refugia of the fruit flies and sprays applied to crops have been used. • Proteinaceous liquid attractants in insecticide sprays is an effective method of controlling melon fly populations. This bait insecticide is sprayed on broad leaf plants that serve as refugia for melon flies. These baits encourage the adults to feed on the spray residue