Species composition and community structure of fruit flies (Diptera: Tephritidae) across major mango-growing regions in Uganda

摘要

The species diversity of tephritid fruit flies in major mango-growing regions in Uganda was monitored over a 2-year period (2010-2012) using fruit bait and lure traps. A total of 368,332 specimens belonging to 10 species in four genera (Bactrocera, Ceratitis, Trirhithrum and Dacus) were collected. Of these, 98.9% belonged to Bactrocera invadens, while the second and third most common species were Dacus bivittatus (0.4%) and Ceratitis anonae (0.3%), respectively. Significant differences in the evenness and diversity of fruit fly species were noted across the regions. Fruit fly community structure was significantly different across the three regions. The Lake Victoria Crescent and Mbale Farmlands harboured significantly more D. ciliatus, T. coffeae, D. bivittatus and B. cucurbitae in contrast to the Northern Moist Farmlands and the Western Medium High Farmlands. Ceratitis rosa contributed the highest difference in regional structure, followed by C. fasciventris and C. cosyra. Rank abundance curves depicted a geometric series distribution of the species composition in the three regions, confirming a scenario of competitive displacement of native fruit fly species by B. invadens. A comprehensive and sustainable response strategy to B. invadens and other fruit flies needs to be urgently devised to protect the horticulture industry in Uganda.