Tephritidae Main | Diptera Home | SEL Home
Fruit Fly (Diptera: Tephritidae) Economic Importance
About 70 species of fruit flies are considered important agricultural pests, and many others are minor or potential pests. (White & Elson-Harris 1992). Fruits are the most important crops attacked, including citrus, mango, apples, and many others, and some seed crops such as sunflower and safflower are also affected. An interactive key for the identification of these pest species may be downloaded from this site.
Fruit flies can also be beneficial. Some 15 species have been used as biological control agents for weedy species of Asteraceae. Other tephritids are key subjects for the study of basic biology (e.g., Mediterranean fruit fly (Ceratitis capitata) in genetics and molecular biology), and some are important models for testing evolutionary or ecological theories, for example, the apple maggot and related species of Rhagoletis for sympatric speciation (Bush 1993), the Mediterranean fruit fly for demographic research (Carey & Liedo 1999)), and various Tephritinae (e.g., Erosta solidaginis and species of Urophora) for resource partitioning and other eclogical studies (Abrahamson & Weis 1997, Zwölfer 1988).
Because of the phytophagous habits of their larvae, many species of Tephritidae inflict heavy losses on fruit and vegetable crops. Economic effects of pest species include not only direct loss of yield and increased control costs, but also the loss of export markets and/or the cost of constructing and maintaining fruit treatment and eradication facilities. In many countries, the exportation of most commercial fruits is severely restricted by quarantine laws to prevent the spread of fruit fly species. The cost of living with an established infestation of Ceratitis capitata or several other major fruit fly pests in California has been estimated at hundreds of millions of dollars annually (Jackson & Lee 1985, Dowell & Wange 1986).
White & Elson-Harris (1992) assessed the pest status and the known host and distribution data for the 100 most economically important species of Tephritidae. They also listed an additional 150 species that have been associated with any economically important plant. Reviews of fruit fly pest status by region are found in Robinson & Hooper (1989, Chapters 2.1-2.8), and Yang et al. (1994) provided a subsequent review for China.
Most pest species of Tephritidae attack fruits, and the great majority of them belong to the genera Anastrepha, Ceratitis, Bactrocera, Dacus and Rhagoletis. The hosts of these flies belong to a wide variety of families of plants, and include many major commercial crops.
The genus Bactrocera is the most economically significant genus, with about 40 species considered to be important pests (White & Elson-Harris 1992). Many of them are highly polyphagous. Bactrocera is native to the Old World tropics, and most of the major pests are from the Oriental and Australasian Regions. The Oriental fruit fly (B. dorsalis) and several closely related species recently revised by Drew & Hancock (1994), the melon fly (B. cucurbitae), the olive fruit fly (B. oleae), the Queensland fruit fly (B. tryoni), and the peach fruit fly (B. zonata) are among the most important species.
Anastrepha is the most economically important genus in the Neotropics. White & Elson-Harris (1992) listed 15 species as significant pests and 28 others that have been reported to attack economically important plants. The worst pest species are the Mexican fruit fly (A. ludens), the West Indian fruit fly (A. obliqua), and the South American fruit fly (A. fraterculus complex).
Rhagoletis includes species in the Holarctic and Neotropical Regions, 17 of which were listed as pests by White & Elson-Harris (1992). The most serious are the apple maggot (R. pomonella), the European and eastern cherry fruit flies (R. cerasi and cingulata), the blueberry maggot (R. mendax), the walnut husk fly (R. completa), R. striatella, a pest of husk tomato, and R. tomatis, a pest of tomato.
Ceratitis species, about ten of which are listed as pests by White & Elson-Harris (1992), are mostly restricted to Africa, except for the Mediterranean fruit fly (C. capitata), which has spread to many tropical and subtropical parts of the world. The Med fly is by far the most notorious pest species in the genus, and it is one of the most polyphagous and widespread species of Tephritidae (Liquido et al. 1991).
Dacus is also a mostly Afrotropical genus, although a few species occur in other parts of the Paleotropics and subtropics. White & Elson-Harris (1992) listed 11 species as pests, mainly on Cucurbitaceae, the most important species being the pumpkin fly (D. bivittatus) and the lesser pumpkin fly (D. ciliatus).
A few additional fruit pest species are found in the genera Carpomya, Euphranta, Monacrostichus, Neoceratitis, Toxotrypana, and Zonosemata. Several leaf- or stem-mining species of Tephritidae, particularly in the genera Euleia, Plioreocepta, Zacerata, and Strauzia, also cause economic losses, and a variety of species of Tephritinae damage seeds of commercial species of Asteraceae, such as sunflower and safflower.
Although fruit flies are commonly thought of as pests, some species are valuable agents for the biological control of weeds (Bess & Haramoto 1972, White & Clement 1987, P. Harris 1989, White & Elson-Harris 1992, Turner 1996). Most species that have been used or tested for biocontrol belong to the subfamily Tephritinae and attack plants of the family Asteraceae. White & Elson-Harris (1992) and Turner (1996) provided the most comprehensive lists of species released or considered as biocontrol agents. The most successful cases of control are summarized below from White & Elson-Harris (1992). Several tephritid species (Chaetorellia, Urophora and Terellia) are included on the site Biological Control: A Guide to Natural Enemies in North America. Also see Introduced Species for a list of additional species introduced for biocontrol.
Eutreta xanthochaeta (lantana gall fly) together with other agents has achieved partial to substantial control of Lantana camara L. in Hawaii. It also was released in Australia and South Africa but did not establish there.
Procecidochares alani has controlled Ageratina riparia (Regel) R. King & H. Robinson in some areas of Hawaii. P. utilis also was introduced there for control of Ageratina adenophora (Sprengel) R. King & H. Robinson. It has been ineffective in wet areas, but has controlled the weed in dry zones. It also was released in Australia, New Zealand, South Africa and Madeira, and has been established in India, Nepal and China, although it has not controlled its host there. In western North America, Urophora stylata has reduced seed production in Cirsium vulgare (Savi) Tenore, and U. affinis and U. quadrifasciata have reduced seed production in Centaurea diffusa Lam. and C. maculosa Lamarck. In the Pacific Northwest, U. affinis and U. quadrifasciata are close to the threshold needed to achieve economic control of spotted knapweed, reducing seed prodution from 50-90%. Six other species of Tephritidae have been established in North America as weed biocontrol agents, but in most cases it is too early to evaluate their effect on the target weeds. In Australia Urophora solstitialis has contributed to the control of nodding thistle (Carduus nutans) (CRC Weeds website).
See the Fruit Fly Bibliography Database for full information for cited references.
|Top of Page||
Content by Allen L. Norrbom. Last Updated: November 10, 2004.